ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS 09244A/09245A-24

TECHNICAL MANUAL 

UNIT, DIRECT SUPPORT AND GENERAL SUPPORT 

MAINTENANCE MANUAL 

DIESEL ENGINE 

MODEL 6068TF151 

6 CYLINDER 6.8 LITER 

(NSN: 2815-01-462-3596) (EIC: N/A) 

DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited 

DEPARTMENTS OF THE ARMY AND THE AIR FORCE 

AND HEADQUARTERS, MARINE CORPS 

1 NOVEMBER 2000

 PCN: 182 092444 00

ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

__________

 WARNING

Where applicable, prior to performing engine maintenance, ensure batteries are 

disconnected to prevent serious injury or death.

 __________

 WARNING

Batteries give off a flammable gas. Do not smoke or use open flame when 

performing maintenance. Failure to comply can cause injury to personnel and 

equipment due to flame and possible explosion. 

 __________

 WARNING

Engine coolant is very hot and under pressure after engine has been operating. 

Allow engine to cool before you slowly loosen filler cap and relieve pressure from 

cooling system. Failure to comply could result in severe personal injury.

 __________

 WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to penetrate the 

skin, causing serious injury. Always direct fuel injection nozzle tip away from 

personnel and place a clear, protective shield around spray zone. Before 

disconnecting fuel lines, be sure to relieve pressure. Before applying pressure to the 

system, be sure all connections are tight and lines, pipes, and hoses are not 

damaged. Keep hands and body away from pinholes and nozzles which eject fuel 

under pressure. Use a piece of cardboard or wood, rather than hands, to search for 

suspected leaks.

 __________

 WARNING

If diesel or JP fuel is injected into the skin, seek medical attention immediately. 

Failure to comply can result in serious injury.

 __________

 WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection required. Avoid repeated/prolonged contact. Provide 

adequate ventilation. Failure to comply could result in serious injury or death.

a
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

 __________

 WARNING

Fuels used in the generator set are flammable. Do not smoke or use open flames 

when performing maintenance. Failure to comply can result in flame and possible 

explosion and can cause injury or death to personnel and damage the generator set. 

 __________

 WARNING

Exhaust system is very hot after operating engine. After operating engine, allow 

exhaust system to cool before removal. Failure to comply could result in personal 

injury.

 __________

 WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. Skin 

and eye protection are required. Avoid repeated/prolonged contact. Provide 

adequate ventilation. Failure to comply could result in serious injury or death.

 __________

 WARNING

Compressed air used for cleaning can create airborne particles that may enter the 

eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection required. Failure 

to comply could result in serious eye damage or blindness.

 __________

 WARNING

Care should be exercised when using steam for cleaning. Steam is extremely hot. 

Skin and eye protection are required. Avoid steam contact with skin.

 __________

 WARNING

Operating the generator set with any access door open exposes personnel to high 

noise levels. Hearing protection must be worn when operating or working near the 

generator set with any access door open. Failure to comply can cause hearing 

damage or loss. 

 __________

 WARNING

Block cylinder head with a solid block of wood at each end of cylinder head while 

using spring compressor. Failure to comply could result in serious personal injury.

b
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

 __________

 WARNING

Do not stand in front of valve spring while compressing valve springs. Failure to 

comply could result in serious personal injury.

 __________

 WARNING

When using bench grinder, eye protection must be worn to prevent particles from 

entering eyes. Failure to comply could result in serious eye damage or blindness.

 __________

 WARNING

Flywheel is heavy. Provide adequate lifting device to support weight. Failure to 

comply could result in serious personal injury.

 __________

 WARNING

Wear protective gloves to help prevent burns from handling hot ring gear.

 __________

 WARNING

Crankshaft is very heavy, do not attempt to remove crankshaft by hand. Use 

proper lifting equipment.

 __________

 WARNING

Oil fumes or oil can ignite above 380°F (193°C). Use a temperature device and do 

not exceed 360°F (182°C). Do not allow a flame or heating element to be in direct 

contact with oil. Heat oil in a well ventilated area. Plan a safe handling procedure 

to avoid burns. Wear protective clothing, gloves, apron, etc.

 __________

 WARNING

The vehicle engine stand should be used only by qualified service technicians 

familiar with this equipment. Failure to comply could result in personal injury 

and/or equipment damage.

c
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

 __________

 WARNING

Use alloy steel SAE Grade 8 or higher socket head cap screws when installing engine 

adapters on vehicle engine stand. Use Thread Lock and Sealer (Loctite 242) or 

equivalent on cap screws when installing lift straps on the engine. Tighten cap 

screws to 125 lb-ft (170 Nm). Failure to comply could result in personal and/or 

equipment damage.

 __________

 WARNING

Be sure that tapped hole on the vehicle repair stand's adapter and mounting hub 

are clean and not damaged. Ensure that thread engagement is within 1-1.2 times 

the screw diameter minimum to properly secure the engine. Failure to comply 

could result in personal injury and/or equipment damage.

__________

WARNING

To avoid structural or personal injury, do not exceed the maximum capacity rating 

or 2000 lbs. (908 kg.). Maximum capacity is determined with the center of the 

engine located no more than 13 inches (330 mm) from the mounting hub surface of 

the engine stand.

 __________

 WARNING

Be sure that the center of the engine must be located within 2 inches (51 mm) of the 

engine stand rotating shaft to prevent unsafe off-balance load condition. Failure to 

comply could result in personal injury and/or equipment damage. 

 __________

 WARNING

Recheck to make sure engine is solidly mounted before releasing support from 

engine lifting device. Failure to comply could result in personal injury and/or 

equipment damage.

 __________

 WARNING

Never permit any part of the body to be positioned under a load being lifted or 

suspended. Failure to comply could result in personal injury.

d
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

__________

WARNING

The lifting jack is to be used when it is necessary to lift the engine 

for rotation. When working on the engine, the jack should be at its 

lowest position to keep the center of gravity low and the possibility 

of tipping low.

__________

WARNING

Unscrew the release valve slowly when lowering the engine on 

vehicle engine stand to prevent sudden engine movement. Do not 

unscrew release valve knob more than two turns from its closed 

position. Failure to comply could result in personal injury and/or 

equipment damage. 

__________

WARNING

 

When adding coolant to the system, use the appropriate coolant solution. Failure to 

comply could result in damage to the engine and injury to personnel. 

_________ 

WARNING

Service tools are designed to aid disassembly and assembly 

procedures. Service tools must be used to prevent possible damage 

to components. Some operations can cause personal injury if 

carried out without use of relevant tools. 

e/f BLANK 

TM 9-2815-260-24 

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NOTE: The portion of the text affected by the changes is indicated by a vertical line in the 

outer margins of the page. Changes to illustrations are indicated by miniature 

pointing hands. Changes to wiring diagrams are indicated by shaded areas. 

Dates of issue for original and changed pages are: 

Original..........0 .............1 November 2000 

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ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

i 

 

Technical Manual 

No. 9-2815-260-24 

Technical Order 

No. 38G1-126-2 

Technical Manual 

No. 09244A/09245A-24 

DEPARTMENTS OF THE ARMY 

AND THE AIR FORCE 

AND HEADQUARTERS, MARINE CORPS 

Washington, DC, 1 November 2000 

UNIT, DIRECT SUPPORT AND GENERAL SUPPORT 

MAINTENANCE MANUAL 

FOR 

DIESEL ENGINE, MODEL 6068TF151 

6 CYLINDER, 6.8 LITER 

(NSN: 2815-01-462-3596) (EIC: N/A) 

REPORTING ERRORS AND RECOMMENDING IMPROVEMENTS 

You can help improve this manual. If you find any mistakes, or if you know of a 

way to improve the procedures, please let us know. Mail your letter, DA Form 

2028 (Recommended Changes to Publications and Blank Forms) or DA Form 

2028-2 located in back of this manual directly to: Commander, US Army 

Communications-Electronics Command and Fort Monmouth, ATTN: AMSELLC-LEO-D-CS-CFO, Fort Monmouth, New Jersey 07703-5006. The fax 

number is 732-532-1413, DSN 992-1413. You may also e-mail your 

recommendations to AMSEL-LC-LEO-PUBS-CHG@mail1.monmouth.army.mil. 

For Air Force, submit AFTO Form 22 (Technical Order System Publication 

Improvement Report and Reply) in accordance with paragraph 6-5, Section VI, 

TO 00-5-1. Forward direct to prime ALC/MST. 

Marine Corps units, submit NAVMC 10772 (Recommended Changes to 

Technical Publications) to: Commanding General, Marine Corps Logistics Base 

(Code 850), Albany, Georgia 31704-5000. 

In any case, we will send you a reply. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24X

ii 

TABLE OF CONTENTS

Chapter/Section Page

HOW TO USE THIS MANUAL............................................................................................................................. viii 

CHAPTER 1 INTRODUCTION ............................................................................................................................. 1-1 

Section I GENERAL INFORMATION ...................................................................................................... 1-1 

Section II EQUIPMENT DESCRIPTION AND DATA.............................................................................. 1-2 

Section III PREPARATION FOR USE......................................................................................................... 1-8 

CHAPTER 2 OPERATING INSTRUCTIONS....................................................................................................... 2-1 

Section I PRINCIPLES OF OPERATION ................................................................................................. 2-1 

Section II OPERATING INSTRUCTIONS ................................................................................................. 2-2 

Section III SPECIAL INSTRUCTIONS........................................................................................................ 2-2 

CHAPTER 3 UNIT MAINTENANCE INSTRUCTIONS...................................................................................... 3-1 

Section I LUBRICATION INSTRUCTIONS............................................................................................. 3-1 

Section II REPAIR PARTS; TOOLS; SPECIAL TOOLS; 

 TEST, MEASUREMENT AND DIAGNOSTIC (TMDE); AND SUPPORT EQUIPMENT.... 3-1 

Section III PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)................................... 3-1 

Section IV TROUBLESHOOTING............................................................................................................... 3-3 

Section V MAINTENANCE PROCEDURES.............................................................................................. 3-15 

CHAPTER 4 DIRECT SUPPORT MAINTENANCE INSTRUCTIONS............................................................... 4-1 

Section I TROUBLESHOOTING............................................................................................................... 4-1 

Section II MAINTENANCE PROCEDURES.............................................................................................. 4-14 

CHAPTER 5 GENERAL SUPPORT MAINTENANCE INSTRUCTIONS........................................................... 5-1 

Section I TROUBLESHOOTING............................................................................................................... 5-1 

Section II MAINTENANCE PROCEDURES ................................................................................................ 5-1 

Appendix A References.................................................................................................................................... A-1 

Appendix B Maintenance Allocation Chart (MAC)......................................................................................... B-1 

Appendix C Components of End Item and Basic Issue Items List ................................................................... C-1 

Appendix D Additional Authorization List ...................................................................................................... D-1 

Appendix E Expendable and Durable Items List ............................................................................................. E-1 

Appendix F Illustrated List of Manufactured Items......................................................................................... F-1 

Appendix G Torque Limits............................................................................................................................... G-1 

Appendix H Mandatory Replacement Parts ..................................................................................................... H-1 

Alphabetical Index................................................................................................................................................... Index-1 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

iii 

LIST OF ILLUSTRATIONS

Figure Page 

Figure 1-1. Engine Components ....................................................................................................................... 1-4 

Figure 1-2. Option Code Label......................................................................................................................... 1-5 

Figure 3-1. Thermostat and Water Manifold/Thermostat Cover ...................................................................... 3-19 

Figure 3-2. Thermostat Installation .................................................................................................................. 3-21 

Figure 3-3. Water Pump Assembly................................................................................................................... 3-22 

Figure 3-4. Battery Charging Alternator and Mounting ................................................................................... 3-24 

Figure 3-5. Starter Solenoid Test Circuit.......................................................................................................... 3-25 

Figure 3-6. Starter Assembly............................................................................................................................ 3-27 

Figure 3-7. Intake Manifold.............................................................................................................................. 3-28 

Figure 3-8. Exhaust Manifold........................................................................................................................... 3-29 

Figure 3-9. Oil Filter Assembly........................................................................................................................ 3-30 

Figure 3-10. Oil Cooler Assembly...................................................................................................................... 3-32 

Figure 3-11. Oil Fill Tube Assembly.................................................................................................................. 3-33 

Figure 3-12. Oil Dipstick Tube Assembly.......................................................................................................... 3-34 

Figure 3-13. Oil Dipstick Tube Installation........................................................................................................ 3-35 

Figure 3-14. Oil Pan ........................................................................................................................................... 3-36 

Figure 3-15. Fuel Filter Assembly...................................................................................................................... 3-39 

Figure 3-16. Fuel Supply Pump.......................................................................................................................... 3-40 

Figure 3-17. Fuel Injection Assembly ................................................................................................................ 3-41 

Figure 4-1. Battery Charging Alternator Test Circuit....................................................................................... 4-14 

Figure 4-2. Battery Charging Alternator Assembly .......................................................................................... 4-16 

Figure 4-3. Stator and Rear Housing Separation .............................................................................................. 4-17 

Figure 4-4. Testing Brush Assembly ................................................................................................................ 4-17 

Figure 4-5. Testing Exciting Diodes................................................................................................................. 4-18 

Figure 4-6. Testing Positive/Negative Diodes.................................................................................................. 4-18 

Figure 4-7. Testing Stator Windings................................................................................................................. 4-19 

Figure 4-8. Testing Rotor ................................................................................................................................. 4-20 

Figure 4-9. Starter Bench Test Setup................................................................................................................ 4-22 

Figure 4-10. Starter Assembly............................................................................................................................ 4-23 

Figure 4-11. Disconnecting Lead Wire (Typical)............................................................................................... 4-24 

Figure 4-12. Removing Through Bolts (Typical) ............................................................................................... 4-24 

Figure 4-13. Removing Starter End Frame and Yoke Assembly (Typical) ........................................................ 4-25 

Figure 4-14. Removing Brushes ......................................................................................................................... 4-25 

Figure 4-15. Removing Armature....................................................................................................................... 4-26 

Figure 4-16. Removing Housing (Typical)......................................................................................................... 4-26 

Figure 4-17. Removing Overrunning Clutch (Typical)....................................................................................... 4-27 

Figure 4-18. Removing Steel Ball ...................................................................................................................... 4-27 

Figure 4-19. Removing Pinion, Retainer, and Rollers (Typical) ........................................................................ 4-28 

Figure 4-20. Removing Washer and Spring........................................................................................................ 4-28 

Figure 4-21. Checking Commutator Run-Out..................................................................................................... 4-29 

Figure 4-22. Measuring Commutator OD........................................................................................................... 4-29 

Figure 4-23. Measuring Segment Mica Depth.................................................................................................... 4-30 

Figure 4-24. Inspecting and Replacing Bearings................................................................................................ 4-30 

Figure 4-25. Measuring Brush Length................................................................................................................ 4-31 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24X

iv 

 LIST OF ILLUSTRATIONS (CONTINUED) 

Figure Page 

Figure 4-26. Checking Overrunning Clutch........................................................................................................ 4-31 

Figure 4-27. Growler Test .................................................................................................................................. 4-32 

Figure 4-28. Testing for Grounded Windings..................................................................................................... 4-32 

Figure 4-29. Checking for Open Circuit Windings............................................................................................. 4-33 

Figure 4-30. Checking Brush Holder Assembly................................................................................................. 4-33 

Figure 4-31. Checking Field Coils...................................................................................................................... 4-34 

Figure 4-32. Checking for Open Field Coil........................................................................................................ 4-34 

Figure 4-33. Installing Brushes........................................................................................................................... 4-35 

Figure 4-34. Installing Cover On Yoke .............................................................................................................. 4-36 

Figure 4-35. Installing Yoke............................................................................................................................... 4-36 

Figure 4-36. Turbocharger.................................................................................................................................. 4-39 

Figure 4-37. Turbocharger Inspection Points ..................................................................................................... 4-40 

Figure 4-38. Inspecting Turbocharger Bearings ................................................................................................. 4-43 

Figure 4-39. Oil Pressure Regulating Valve Assembly ...................................................................................... 4-47 

Figure 4-40 Pick-Up Tube Assembly ................................................................................................................ 4-49 

Figure 4-41. Separating Gear and Shaft.............................................................................................................. 4-52 

Figure 4-42. Check Timing Marks ..................................................................................................................... 4-53 

Figure 4-43. Fuel Injection Pump Pressure Outlet Ports .................................................................................... 4-55 

Figure 4-44. Fuel Injection Nozzle Assembly ................................................................................................... 4-59 

Figure 4-45. Rocker Arm Cover......................................................................................................................... 4-65 

Figure 4-46. Engine Timing Hole Location........................................................................................................ 4-66 

Figure 4-47. Rocker Arm Location..................................................................................................................... 4-67 

Figure 4-48. Rocker Arm Assembly................................................................................................................... 4-70 

Figure 4-49. Cylinder Head Assembly ............................................................................................................... 4-75 

Figure 4-50. Fuel Transfer Pump Push Rod Location ........................................................................................ 4-76 

Figure 4-51. Valve Recess Measurement ........................................................................................................... 4-76 

Figure 4-52. Cylinder Head Capscrew Torque Sequence................................................................................... 4-79 

Figure 4-53 Flywheel Flatness........................................................................................................................... 4-82 

Figure 4-54. Flywheel Removal ......................................................................................................................... 4-82 

Figure 4-55. Flywheel Ring Gear ....................................................................................................................... 4-83 

Figure 4-56. Removal of Rear Crankshaft Oil Seal ............................................................................................ 4-84 

Figure 4-57. Rear Crankshaft Oil Seal Installation............................................................................................. 4-86 

Figure 4-58. Flywheel and Housing Assembly................................................................................................... 4-88 

Figure 4-59. Gasket Application to Cylinder Block ........................................................................................... 4-89 

Figure 4-60. Crankshaft Pulley........................................................................................................................... 4-91 

Figure 4-61. Fan Drive Assembly....................................................................................................................... 4-93 

Figure 4-62. Timing Gear Cover ........................................................................................................................ 4-95 

Figure 4-63. Engine Lifting ................................................................................................................................ 4-100 

Figure 5-1. Fuel Injection Pump....................................................................................................................... 5-6 

Figure 5-2. Clip Removal ................................................................................................................................. 5-9 

Figure 5-3. Droop Control Locking Cap Removal ........................................................................................... 5-9 

Figure 5-4. Control Rod Assembly and Governor Spring Removal ................................................................. 5-10 

Figure 5-5. Cam Advance Pin Removal ........................................................................................................... 5-11 

Figure 5-6. Reed Valve Removal. .................................................................................................................... 5-11 

Figure 5-7. Linkage Hook Disconnection......................................................................................................... 5-12 

Figure 5-8. Hydraulic Head Assembly Removal. ............................................................................................. 5-12 

 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

v 

LIST OF ILLUSTRATIONS (CONTINUED) 

Figure Page 

Figure 5-9. Governor Arm and Linkage Hook Removal .................................................................................. 5-13 

Figure 5-10. Drive Shaft Bearing and Seal Removal (Shown Removed) .......................................................... 5-14 

Figure 5-11. Transfer Pump End Cap Seal Removal (Typical). ......................................................................... 5-14 

Figure 5-12. Cam Ring Removal........................................................................................................................ 5-15 

Figure 5-13. Pumping Plunger Removal............................................................................................................. 5-15 

Figure 5-14. Delivery Valve Removal................................................................................................................ 5-16 

Figure 5-15. Retaining Clip Removal................................................................................................................. 5-16 

Figure 5-16. Fuel Injection Housing................................................................................................................... 5-17 

Figure 5-17. Drive Shaft..................................................................................................................................... 5-18 

Figure 5-18. Cam Ring ....................................................................................................................................... 5-19 

Figure 5-19. Hydraulic Head Assembly (Typical).............................................................................................. 5-20 

Figure 5-20. Distributor Rotor Assembly (Typical) ........................................................................................... 5-20 

Figure 5-21. Shoes and Rollers........................................................................................................................... 5-21 

Figure 5-22. Leaf Springs................................................................................................................................... 5-21 

Figure 5-23. Transfer Pump Blades.................................................................................................................... 5-22 

Figure 5-24. Transfer Pump Liner ...................................................................................................................... 5-23 

Figure 5-25. Transfer Pump Regulating Piston and Adjusting Screw ................................................................ 5-23 

Figure 5-26. Transfer Pump Regulator Assembly .............................................................................................. 5-24 

Figure 5-27. Metering Valve and Arm Assembly............................................................................................... 5-25 

Figure 5-28. Delivery Valve............................................................................................................................... 5-25 

Figure 5-29. Fuel Side Seal Installation.............................................................................................................. 5-26 

Figure 5-30. Oil Side Seal Installation................................................................................................................ 5-27 

Figure 5-31. Drive Shaft Bearing Installation..................................................................................................... 5-27 

Figure 5-32. Seal Protection Tube...................................................................................................................... 5-28 

Figure 5-33. Thrust Bearing and Thrust Washer ................................................................................................ 5-28 

Figure 5-34. Spring Washer and Retaining Ring ............................................................................................... 5-29 

Figure 5-35. Timing Mark Locator..................................................................................................................... 5-29 

Figure 5-36. Weight Retaining Assembly........................................................................................................... 5-30 

Figure 5-37. Tightening Delivery Valve Stop Screw.......................................................................................... 5-30 

Figure 5-38. Pumping Plunger Installation......................................................................................................... 5-31 

Figure 5-39. Installing Rollers and Shoes (Typical)........................................................................................... 5-31

Figure 5-40. Measuring Roller to Roller Dimension .......................................................................................... 5-32 

Figure 5-41. Transfer Pump Liner Installation (Typical).................................................................................... 5-33 

Figure 5-42. Transfer Pump Blade Installation (Typical)................................................................................... 5-33 

Figure 5-43. Regulator Assembly Installation (Typical) .................................................................................... 5-34 

Figure 5-44. Governor Weight Installation (Typical)......................................................................................... 5-35 

Figure 5-45. Thrust Washer Installation (Typical) ............................................................................................. 5-35 

Figure 5-46. Thrust Sleeve Installation (Typical)............................................................................................... 5-36 

Figure 5-47. Head and Rotor Assembly Installation (Typical)........................................................................... 5-36 

Figure 5-48. Control Spring Installation............................................................................................................. 5-37 

Figure 5-49. Control Rod Installation................................................................................................................. 5-38 

Figure 5-50. Droop Control Locking Cap Installation........................................................................................ 5-38 

Figure 5-51. Damper Barrel and Piston.............................................................................................................. 5-39 

Figure 5-52. Throttle Installation........................................................................................................................ 5-39 

Figure 5-53. Setting Governor Linkage Gap ...................................................................................................... 5-40 

Figure 5-54. Reed Valve Assembly.................................................................................................................... 5-41 

Figure 5-55. Piston and Piston Ring Seal ........................................................................................................... 5-41 

Figure 5-56. Piston Ring..................................................................................................................................... 5-42 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24X

vi 

LIST OF ILLUSTRATIONS (CONTINUED) 

Figure Page 

Figure 5-57. Piston Ring Compressor................................................................................................................. 5-42 

Figure 5-58. Piston in Power Side Piston Hole .................................................................................................. 5-43 

Figure 5-59. Power Side Piston Hole Plug Installation ...................................................................................... 5-43 

Figure 5-60. Aligning Pin Hole in Piston ........................................................................................................... 5-44 

Figure 5-61. Camshaft ........................................................................................................................................ 5-47 

Figure 5-62. Measuring Camshaft Lobe Height ................................................................................................. 5-50 

Figure 5-63. Idler Gears ..................................................................................................................................... 5-55 

Figure 5-64. Spring Pin Protrusion..................................................................................................................... 5-56 

Figure 5-65. Front Plate...................................................................................................................................... 5-57 

Figure 5-66. Front Plate Sealant Application ..................................................................................................... 5-59 

Figure 5-67. Crankshaft and Main Bearings....................................................................................................... 5-60 

Figure 5-68. Critical Areas of Crankshaft Load Stress ....................................................................................... 5-63 

Figure 5-69. Measuring Main Thrust Journal and Thrust Bearing Width........................................................... 5-65 

Figure 5-70. Fastening Cylinder Liners .............................................................................................................. 5-71 

Figure 5-71. Removing Carbon From Cylinder Liners....................................................................................... 5-71 

Figure 5-72. Pistons, Connecting Rods and Cylinder Liners.............................................................................. 5-74 

Figure 5-73. Piston Inspection (Defects Exaggerated) ....................................................................................... 5-75 

Figure 5-74. Checking Piston Keystone Ring Groove Wear .............................................................................. 5-75 

Figure 5-75. Measuring Piston Ring Groove Clearance ..................................................................................... 5-76 

Figure 5-76. Measuring Piston Skirt................................................................................................................... 5-76 

Figure 5-77. Measuring Rod Center-to-Center Bores ........................................................................................ 5-80 

Figure 5-78. Inspecting Cylinder Liner Pitting................................................................................................... 5-85 

Figure 5-79. Inspecting Piston Cooling Orifice.................................................................................................. 5-92 

Figure 5-80. Oil Gallery Plugs............................................................................................................................ 5-92 

Figure 5-81. Inspecting Cylinder Block.............................................................................................................. 5-94 

Figure 5-82. Measuring Main Bearing Bore....................................................................................................... 5-95 

Figure 5-83. Measuring Cam Follower Bore Diameter ...................................................................................... 5-95 

Figure 5-84. Measuring Camshaft Bore Diameter.............................................................................................. 5-96 

Figure 5-85. Measuring Cylinder Block Top Deck Flatness .............................................................................. 5-96 

Figure 5-86. Oil Pump Assembly ....................................................................................................................... 5-99 

Figure 5-87. Oil Pump Axial Clearance ............................................................................................................ 5-101 

Figure 5-88. Oil Pump Radial Clearance Measurement ..................................................................................... 5-101 

Figure 5-89. Oil Bypass Valve. .......................................................................................................................... 5-103 

Figure 5-90. Valve Face Angle........................................................................................................................... 5-106 

Figure 5-91. Measuring Cylinder Head Thickness ............................................................................................. 5-108 

Figure 5-92. Valve Seat Removal Chisel............................................................................................................ 5-111 

Figure 5-93. Removal of Valve Seat Insert ........................................................................................................ 5-111 

Figure 5-94. Valve Seat Bore in Cylinder Head ................................................................................................ 5-112 

Figure 5-95. Valve Guide Installation ................................................................................................................ 5-113 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

vii 

LIST OF TABLES

Table Page 

Table 1-1. Table of Specifications .................................................................................................................. 1-5 

Table 1-2. Engine Option Codes - 6 Cylinder, 6.8 Liter ................................................................................. 1-6 

Table 3-1. Preventive Maintenance Checks and Services (PMCS)................................................................. 3-2 

Table 3-2. Unit Troubleshooting..................................................................................................................... 3-4 

Table 4-1. Direct Support Troubleshooting..................................................................................................... 4-2 

Table 4-2. Valve Clearance Specification (Rocker Arm-To-Valve Tip)......................................................... 4-68 

Table 4-3. Valve Lift Specifications at 0.00 in. (mm) Valve Clearance.......................................................... 4-69 

Table 4-4. Valve Recess Specifications .......................................................................................................... 4-77 

Table 4-5. Cylinder Block Top Deck Specifications....................................................................................... 4-78 

Table 4-6. Flywheel Face Flatness Specifications........................................................................................... 4-82 

Table 5-1. Procedural Index for General Support Maintenance...................................................................... 5-1 

Table 5-2. Fuel Injection Pump Checks .......................................................................................................... 5-5 

Table 5-3. Camshaft Lobe Height Specifications............................................................................................ 5-51 

Table 5-4. Camshaft and Timing Gear Train Specifications ........................................................................... 5-53 

Table 5-5. Crankshaft and Main Bearings Specifications ............................................................................... 5-64 

Table 5-6. Connecting Rod Journal and Bearing Specifications ..................................................................... 5-77 

Table 5-7. Connecting Rod Bore (Without Bearing Inserts) Specifications.................................................... 5-78 

Table 5-8. Connecting Rod Piston Pin Bushing Specifications....................................................................... 5-79 

Table 5-9. Cylinder Liner Height Specifications............................................................................................. 5-83 

Table 5-10. Cylinder Liner Thickness Specifications........................................................................................ 5-87 

Table 5-11. Piston and Cylinder Liner Specifications....................................................................................... 5-87 

Table 5-12. Valve Seat Bore Insert Specifications............................................................................................ 5-113 
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HOW TO USE THIS MANUAL

In this manual (TM 9-2815-260-24) paragraphs are underlined and sections and chapters appear in capital letters. The 

location of additional material that must be referenced is clearly marked. Illustrations in this text are located as close as 

possible to their references. 

Chapter 1 - INTRODUCTION. This section contains general information, equipment description and data, and principles of 

operation for the engine. 

Chapter 2 - OPERATING INSTRUCTIONS. This section contains functional descriptions of the engine systems and how 

they are connected to the end item. For operation, refer to end item operator's manual. 

Chapter 3 - UNIT MAINTENANCE INSTRUCTIONS. This section contains troubleshooting procedures used to recognize 

and correct engine malfunctions at the unit level, and all maintenance procedures authorized to be performed on the engine 

the unit level. 

Chapter 4 - DIRECT SUPPORT MAINTENANCE INSTRUCTIONS. This section contains direct support level 

troubleshooting procedures used to recognize and correct engine malfunctions at the direct support level, and all maintenance 

procedures authorized to be performed on the engine at the direct support level. 

Chapter 5 - GENERAL SUPPORT MAINTENANCE INSTRUCTIONS. This section contains general support maintenance 

instructions which are limited to the disassembly, cleaning, inspection and assembly of components after troubleshooting has 

already been accomplished. 

APPENDICES. 

Appendix A lists all forms, field manuals, technical manuals and miscellaneous publications referenced in this manual and 

should be used in conjunction with this manual. 

Appendix B is the Maintenance Allocation Chart (MAC) which designates all maintenance and repair functions authorized to 

be performed at the different maintenance levels. 

Appendix C lists the Components of End Item (COEI) and Basic Issue Items (BII) lists. 

Appendix D. Refer to End Item Maintenance Manual Appendix D for lists of items authorized for use with the generator set, 

but not issued with it or supported by generator set engineering drawings. 

Appendix E lists expendable supplies and materials required to operate and maintain the generator set. These items are 

authorized by CTA 50-970, Expendable Items (except medical, Class V, repair parts, and heraldic items). 

Appendix F includes complete instructions for fabricating or assembling parts as required for the engine. 

Appendix G provides torque limits for fasteners used in maintenance of the engine. 

Appendix H lists parts that must be replaced if removed during maintenance. 
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CHAPTER 1 

 INTRODUCTION

 

Section I. GENERAL INFORMATION

1.1. SCOPE.

a. Type of Manual. This manual contains unit, direct support, and general support maintenance 

instructions for the Model TO6068TF151 Diesel Engine, hereafter referred to as engine. Also 

included are descriptions of major systems/components and their functions in relation to other 

systems/components. 

b. Purpose of Equipment. The engine provides a driving force for generators or other equipment 

requiring this size (HP rating) and compatibility. 

1.2. MAINTENANCE FORMS, RECORDS, AND REPORTS. 

a. Reports of Maintenance and Unsatisfactory Equipment. Department of the Army forms and 

procedures used for equipment maintenance will be those prescribed by DA Pam 738-750, Army 

Maintenance Management System (TAMMS). Air Force personnel will use AFR 66-1, Air Force 

Maintenance Management Policy, for maintenance reporting and TO-OO-35D54 for unsatisfactory 

equipment reporting. 

b. Reporting of Item and Packaging Discrepancies. Fill out and forward SF 364 (Report of 

Discrepancy (ROD)) as prescribed in AR 735-1l-2/DLAR 414-55/SECNAVINST 4355.18/AFR 

400-54/MCO 4430.3J. 

c. Transportation Discrepancy Report (TDR) (SF 361). Fill out and forward Transportation 

Discrepancy Report (TDR) (SF361) as prescribed in AR 55-38/NAVSUPINST 4610.33C/AFR 75-

18/MCO P4610.19D/DLAR 4500.15. 

1.3. REPORTING EQUIPMENT IMPROVEMENT RECOMMENDATIONS (EIR).

Army - If your equipment needs improvement, let us know. Send us an EIR. You, the user, are the only 

one who can tell us what you don’t like about your equipment. Let us know why you don’t like the design 

or performance. Put it on a SF 368 (Product Quality Deficiency Report). Mail it to us at the address below. 

 We’ll send you a reply. The fax number is 908-532-1413, DSN 992-1413. You may also e-mail your 

recommendations to AMSEL-LC-LEO-PUBS-CHG@cecom3.monmouth.army.mil. 

Commander 

U.S. Army Communications and Electronics Command (CECOM) 

ATTN: AMSEL-LC-LEO-D-CS-CFO 

Fort Monmouth, New Jersey 07703-5008 

 (AF) USAF Deficiency Reporting and Investigating System, TO 00-35D-54, Appendix A procedures 

will be used for electronic submission. Submit mailed forms to: 

 SMALC/LHCABD 

 5029 Dudley Boulevard 

 McClellan AFB, CA 95652-1095 
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 (MC) Quality Deficiency Reports (QDR) shall be submitted on SF 368 in accordance with MCO 

4855.10. Submissions may also be made using NAVMC Form 10772. Submit directly to: 

 Commander 

 Marine Corps Logistics Bases 

 (Code 856) 

 Albany, GA 31704-5000 

 A reply will be furnished to you. 

1.4. DESTRUCTION OF ARMY MATERIAL TO PREVENT ENEMY USE.

Refer to TM 750-244-3 for procedures to destroy equipment to prevent enemy use. 

1.5. CORRISION PREVENTION AND CONTROL.

Refer to Corrosion and Corrosion Prevention: Metals, MIL-HDBK-729. 

1.6. PREPARATION FOR STORAGE OR SHIPMENT.

Refer to TB 740-97-2 for procedures to place the equipment into storage. 

1.7. WARRANTY. 

The engine is warranted for a specific period of time. Refer to Warranty Technical Bulletin for the end item. The 

warranty begins from the date stamped on the data plate. Report all defects in material or workmanship to your 

supervisor, who will take appropriate action. 

Section II. EQUIPMENT DESCRIPTION AND DATA

1.8. GENERAL.

The diesel engine (Figure 1-1) is six cylinder, four cycle, fuel injected, turbocharged, and liquid cooled. The firing 

order is 1-5-3-6-2-4. The number one cylinder is toward the fan end of the engine. The serial number is found on 

top of valve cover. Rotation of engine is counterclockwise as viewed from rear of engine facing forward. 

NOTE

All locations referenced herein are given from rear of engine facing forward. 

1.9. DETAILED DESCRIPTION.

a. Turbocharger. A turbocharger, operated by exhaust gases, compresses intake air and routes it to the 

combustion chamber. 

b. Camshaft. The camshaft is driven by an intermediate gear in the timing gear train which meshes with the 

crankshaft gear. Camshaft rotates in honed machined bores in cylinder block; no bushings are used. The 

camshaft lobes determine the time and rate of opening of each valve and actuates the fuel supply pump. 
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c. Intake and Exhaust Valves. Intake and exhaust valves are operated by cam followers, push rods, and 

rocker arm assembly. Valve seat inserts in cylinder head are used for intake and exhaust valves. 

d. Crankshaft. The crankshaft is a one-piece, heat treated, steel forging which operates in replaceable twopiece main bearings. The rear thrust bearing has a flange on each side to support crankshaft thrust and to limit 

end play. 

e. Cylinder Liners and Pistons. Cylinder liners are "wet" (surrounded by coolant) and are individually 

replaceable. O-rings are used to seal the connection between cylinder block and liners. Pistons are made of 

cast high-grade aluminum alloy with internal ribbing. The skirt is cam ground to allow for expansion when 

heated during operation. The piston crown has a cut-out swivel cup with a truncated cone in the center. Two 

compression rings and one oil control ring are used. The top compression ring is a keystone type ring. All 

piston rings are located above the piston pin. The hardened piston pins are fully-floating and held in position 

by means of retainer rings. Spray jets (piston cooling orifices) in cylinder block direct pressurized oil to 

lubricate piston pins and cool pistons. Connecting rods are forged steel and have replaceable bushing and 

bearing inserts. 

f. Cooling System. The cooling system consists of a radiator, water pump, cooling fan, thermostat, and 

connecting hoses. The fan and water pump are both belt driven from the crankshaft pulley. The thermostats 

control engine temperature and are installed in top of engine. The function of the cooling system is to 

maintain a specific operating temperature of 180 to 220°F (82 to 104°C) for the engine. 

g. Lubrication System. The lubrication system consists of oil pan (sump), a gear type pump, full flow 

spin-on oil filter with built-in bypass valve, oil cooler with built-in bypass valve, pressure regulating 

valve, bypass valve, and the internal passages. 

h. Fuel System. The function of the fuel system is to inject a metered quantity of clean atomized fuel 

into the engine cylinders at a precise time near the end of the compression stroke of each piston. The 

fuel system consists of the fuel tank, fuel filter/water separator, fuel supply pump, fuel injection pump, 

and the fuel injectors. The fuel tank is not mounted on the engine. The fuel supply pump is mounted to 

the block and is driven by the camshaft. The fuel injection pump is mounted on the front plate and is 

driven by an intermediate gear in the timing gear train meshing with crankshaft gear. 

i. Electrical System. The electrical system is 28VDC operation and consists of a battery charging 

alternator, starter, externally mounted batteries, and other items as required. The battery charging 

alternator is mounted on front of engine and is belt driven. When engine is operating, the battery 

charging alternator supplies 28VDC to recharge the batteries and maintain them at a full state of charge. 

 The starter is mounted on the flywheel housing, and when energized, engages the ring gear of the 

flywheel to rotate the engine. 
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FIGURE 1-1. ENGINE COMPONENTS 
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1.10. EQUIPMENT DATA. 

Leading Particulars. For a list of Leading Particulars, refer to TABLE 1-1. 

TABLE 1-1. TABLE OF SPECIFICATIONS

Model ................................................................................... John Deere 6068TF151 

Type .................................................................................... EPA compliant six cylinder, four cycle, 

turbocharged diesel 

Bore .................................................................................... 4.19 in. (106 mm) 

Stroke ................................................................................... 5.00 (127.0 mm) 

Displacement........................................................................ 414 cu in. (6.8 liters) 

Compression Ratio ............................................................... 17.0:1 

Firing Order.......................................................................... 1-5-3-6-2-4 

Width.................................................................................... 23.5 in. (598 mm) 

Height................................................................................... 38.7 in. (984 mm) 

Length .................................................................................. 44.0 in. (1117 mm) 

Weight.................................................................................. 1172 lbs (533 kg) 

Injection Pump/Governor..................................................... Stanadyne Model DB4 

Injection Starting Pressure 

New............................................................................. 3,660 psi (25,200 kPa) min 

Used ............................................................................ 3,330 psi (22,950 kPa) min 

Cylinder Compression Pressure .................................. 350 psi (2400 kPa) min 

Lubrication System Capacity................................................ 20.0 qts (19 liters) 

Coolant System capacity (engine only) ................................ 20.5 qts. (19.4 liters) 

Alternator ............................................................................. Bosch 28 volt DC - 45 amp 

Starter................................................................................... Nippon-Denso 24 volt DC - 4.5 kw 

1.11 DATA PLATES.

Refer to Table 1-2 for the engine option codes. The engine option codes data plate is affixed to the top of the rocker arm 

cover (4, Figure 1-1). These codes indicate which of the engine options were installed on your engine at the factory. 

These codes are important when parts and service are required. The engine option code includes an engine base code (1, 

Figure 1-2) which identifies the basic engine installed. The engine option code consists of a four-digit number. The first 

two digits of each code identify a specific group, such as alternators. The last two digits of each code identify one 

specific option provided on your engine, such as 12-volt, 55-amp alternator. If an engine is ordered without a particular 

component, the last two digits of that functional group option code will be 99, 00, or XX. 

FIGURE 1-2. OPTION CODE LABEL 
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Table 1-2. ENGINE OPTION CODES - 6 CYLINDER, 6.8 LITER (CONTINUED) 

ENGINE BASE CODE: 2136F 

OPTION 

CODES DESCRIPTION REMARKS 

1104 Rocker Arm Cover 

1215 Oil Filler Neck 

1306 Crankshaft Pulley 

1426 Flywheel Housing 

1544 Flywheel 

1681 Fuel Injection Pump 

1729 Air Inlet 

1907 Oil Pan 

2001 Water Pump 

2112 Thermostat Cover 

2201 Thermostat 

2301 Fan Drive 

2486 Fan Belt 

2599 Fan Not installed on engine at factory. 

2699 Engine Coolant Heater Not installed on engine at factory. 

2808 Exhaust Manifold 

2999 Ventilator System Not installed on engine at factory. 

3044 Starting Motor 

3110 Alternator 

3518 Fuel Filter 

3601 Front Plate 

3702 Fuel Transfer Pump 

3999 Thermostat Housing Not installed on engine at factory. 

4019 Oil Dipstick 

4199 Belt Driven Front Auxiliary Drive Not installed on engine at factory. 

4399 Starting Aid Not installed on engine at factory. 

4401 Timing Gear Cover with Gears 

4603 Cylinder Block With Liners and Camshaft 

4702 Crankshaft and Bearings 

4807 Connecting Rods and Pistons 
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Table 1-2. ENGINE OPTION CODES - 6 CYLINDER, 6.8 LITER (CONTINUED) 

ENGINE BASE CODE: 2136F 

OPTION 

CODES DESCRIPTION REMARKS 

4902 Valve Actuating Mechanisms 

5001 Oil Pump 

5107 Cylinder Head With Valves 

5707 Water Pump Inlet 

5901 Oil Cooler 

6099 Add-on Auxiliary Drive Pulley Not installed on engine at factory. 

6212 Alternator Mounting 

6499 Exhaust Elbow Not installed on engine at factory. 

6504 Turbocharger 

6699 Temperature Switch Not installed on engine at factory. 

6799 Electronic Tachometer Sensor Not installed on engine at factory. 

6801 Damper 

7499 Air Conditioner Compressor Mounting Not installed on engine at factory. 

7699 Oil Pressure Switch Not installed on engine at factory. 

8604 Fan Pulley 

8799 Automatic Belt Tensioner Not installed on engine at factory. 

8801 Oil Filter 
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Section III. PREPARATION FOR USE

1.12. INSPECTING AND SERVICING ENGINE.

This section provides information and guidance for inspecting, servicing, and installing the engine. For additional 

information, refer to end item maintenance manual. 

a. Inspection.

Check that all packing materials have been removed. 

Check engine identification plate for positive identification. 

Inspect engine exterior for shipping damage. 

Check fan drive belt for proper tension. Refer to end item maintenance manual. 

Inspect engine for loose or missing mounting hardware, or damaged or missing parts. 

b. Service.

Except for servicing the lubrication system, all other servicing must be accomplished after engine is mounted in the 

end item. Refer to the end item maintenance manual. 
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CHAPTER 2 

 OPERATING INSTRUCTIONS 

 Section I. PRINCIPLES OF OPERATION

2.1. INTRODUCTION.

This section contains functional descriptions of the engine systems and how they are connected to the end item. 

2.2. COOLING SYSTEM.

The cooling system consists of a radiator, hoses, a thermostat, a belt driven fan, a water pump, and cooling jackets 

within the engine. The water pump forces coolant through passages (coolant jackets) in the engine block and oil 

cooler where coolant absorbs heat from the engine. When the coolant temperature is below operating temperature, 

the thermostat is closed and coolant is bypassed to the water pump inlet. As coolant temperature increases to 180Ε F 

(82Ε C), the thermostat fully opens, shutting off all bypass flow and providing full flow through the radiator. Air 

forced through the fins of the radiator by the fan cools the coolant pumped through the radiator. Items are added to 

the engine to monitor coolant temperature and to warn if temperature exceeds a predetermined value. 

2.3. LUBRICATION SYSTEM.

The pressure lubrication system consists of a positive displacement gear-driven pump, filter strainer in the suction 

pipe, full flow oil filter, oil cooler, oil pressure regulating valve, and oil bypass valve. Additionally, the oil cooler 

and oil filter have their own bypass valve. The pump draws lubrication oil from the crankcase through a strainer and 

a suction line. The oil is then pumped through an oil line to the oil cooler, oil filter, and through the main oil gallery 

of the cylinder block. From the oil gallery, oil is forwarded under pressure to the main bearings and spray jets to 

cool the pistons. Drilled cross passages in the crankshaft distribute oil from the main bearings to connecting rod 

bearings and camshaft bearings. A drilled passage from the rear camshaft bearing through the cylinder block and 

cylinder head supplies lubricating oil to the rocker arm shaft. A turbocharger oil supply line provides lubricating oil 

to the shaft of the turbocharger. Items are added to monitor oil pressure and to warn the operator or stop the engine 

if pressure drops to a dangerously low value. 

2.4. FUEL SYSTEM.

The fuel system consists of an external fuel tank, fuel supply pump, fuel filter, fuel injection pump, fuel injectors, 

and piping. The fuel supply pump draws fuel from the tank and pressurizes it. This pressure permits the fuel to flow 

through the fuel filter and charge the transfer pump of the fuel injection pump. With the fuel injection pump charged 

with fuel by the fuel supply pump, the fuel injection pump plungers pressurize the fuel to approximately 3,660 psi 

(25,200 kPa). Delivery (pressure) lines are used to route this high pressure fuel to the fuel injection nozzles. Fuel 

enters the injection nozzle at a pressure which easily overcomes the pressure required to open the nozzle valve. 

When the nozzle valve opens, fuel is forced out through the orifices in the nozzle tip and atomizes as it enters the 

combustion chamber. The fuel that is not used by the injectors and injection pump is returned to the fuel tank via an 

excess fuel return line. 
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2.5. ELECTRICAL SYSTEM.

The electrical system consists of external mounted batteries, starter, battery charging alternator, and related relays 

and switches for control of the system. Battery power supplied to the starter during the start cycle energizes the 

starter which engages the ring gear of the flywheel causing the engine to turn over. When engine start is complete, 

the starter is deenergized and disengages from the flywheel. The battery charging alternator is belt driven. It is a 45 

ampere, 28 VDC alternator that when operating supplies voltage to recharge the batteries and maintain them at a full 

state of charge. 

Section II. OPERATING INSTRUCTIONS 

 (Refer to end item operator's manual.) 

Section III. SPECIAL INSTRUCTIONS.

2.6. NUCLEAR, BIOLOGICAL, CHEMICAL (NBC) DECONTAMINATION PROCEDURES. The engine is 

capable of being operated by personnel wearing nuclear, biological, or chemical (NBC) protective clothing without 

special tools or support equipment. Refer to FM 3-5, NBC Decontamination for information on decontamination 

procedures. Specific procedures for the engine are the following: 

a. Rubber tubing and belts, coverings for electrical conduits, gaskets, and bushings will absorb and 

retain chemical agents. Replacement of these items is the recommended method of 

decontamination. 

b. Lubricants, fuel, and coolant may be present on the external surfaces of the generator set or 

components due to leaks or normal operation. These fluids will absorb NBC agents. The 

preferred method of decontamination is removal of these fluids using conventional 

decontamination methods in accordance with FM 3-5. 

c. The primary area that will entrap contaminants on the engine, making efficient decontamination 

extremely difficult, include the area around the external fuel drain. Replacement of this item, if 

available, is the recommended method of decontamination. Conventional decontamination 

methods should be used on this area, while stressing the importance of thoroughness and the 

probability of some degree of continuing contact and vapor hazard. 

d. In an NBC contaminated environment, all access doors on the end item unit should be closed to 

reduce the effects of contamination. 

e. The use of overhead shelters or chemical protective covers is recommended as an additional means 

of protection against contamination in accordance with FM 3-5. When using covers, care should 

be taken to provide adequate space for air flow and exhaust. 

f. For additional NBC information refer to FM 3-3, FM 3-4 and FM 3-5. Other services use 

applicable publications for NBC. 
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CHAPTER 3 

UNIT MAINTENANCE INSTRUCTIONS 

Section I. LUBRICATION INSTRUCTIONS 

3.1. LUBRICATION INSTRUCTIONS.

Refer to TM 9-6115-672-14 for special lubrication instructions. Refer to unit level Preventive Maintenance Checks 

and Services (PMCS) Table 3-1 for lubrication intervals. 

Section II. REPAIR PARTS; TOOLS; SPECIAL TOOLS; TEST, MEASUREMENT AND 

 DIAGNOSTIC (TMDE); AND SUPPORT EQUIPMENT 

3.2. MAINTENANCE REPAIR PARTS.

Repair parts and equipment are listed and illustrated in the Repair Parts and Special Tools List (RPSTL) manual TM 

9-2815-260-24P. 

3.3. TOOLS AND EQUIPMENT.

There are no special tools or support equipment required to perform unit level of maintenance on the engine. A list 

of recommended tools and support equipment required to maintain the engine is contained in Appendix B, 

SECTION III. 

3.4. FABRICATION OF TOOLS AND EQUIPMENT.

There are no fabricated tools/equipment required to perform unit level of maintenance on the engine. For 

fabrication of tools and equipment for maintenance of the engine, refer to Appendix F -Illustrated List of 

Manufactured Items. 

Section III. PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS) 

3.5. PMCS PROCEDURES.

 

a. General. To ensure that engine is ready for operation at all times, it must be inspected so defects can be 

discovered and corrected before they result in serious damage or failure. Perform Generator Set PMCS 

prior to or in conjunction with performance of engine PMCS. For engine PMCS, refer to Table 3-1. 

b. Purpose of PMCS Table. Your Preventive Maintenance Checks and Services table lists the inspections and 

care of your equipment required to keep it in good operating condition. 

c. Purpose of Service Intervals. The interval column of your PMCS table tells you when to do a certain check 

or service. 

d. Procedures Column. The procedures column of your PMCS table tells you how to do the required checks 

and services. Carefully follow these instructions. 

e. The "Equipment Is Not Ready / Available If" column. This column tells you when and why the engine 

cannot be used. 
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NOTE 

The terms ready / available and mission capable refer to the same status: 

Engine is on hand and is able to perform its combat missions (see DA Pam 

738-750). 

f. Reporting and Correcting Deficiencies. If your engine does not perform as required, refer to 

Troubleshooting section for possible problems. Report any malfunctions or failures on DA form 2404, or 

refer to DA Pam 738-750. 

TABLE 3-1. Preventive Maintenance Checks and Services (PMCS)

M – Monthly Q – Quarterly S – Semi-annually A – Annually B – Bi-annually H – Hours 

Item Interval 

No. M Q S A B H 

Item to be 

Inspected 

Procedures Check for and have repaired 

or adjusted as necessary 

Equipment is Not 

Ready/ Available If: 

CAUTION

Engine oil and filter must be changed at a hard time interval of 100 hours on initial 

break-in. Failure to change the oil and filter may void the warranty. 

1 M 300 Oil Filter Refer to paragraph 3.11.2. 

NOTE 

Oil filter change interval is a hard time 

replacement to be used when AOAP 

lab is not available.

2 M 1500 Engine 

Compression 

Check engine compression. Refer to 

paragraph 3.7.1. 

Engine compression 

is low. 

3 M 1500 Engine Oil 

Pressure 

Check engine oil pressure. Refer to TM 

9-6115-672-14. 

Engine oil pressure 

not as specified 

 NOTE 

The following PMCS items are Direct 

Support maintenance tasks.

4 M 1500 Engine Valves Adjust engine valves at Direct Support 

maintenance level. See paragraph 4.7.2. 

5 M 1500 Engine Fuel 

Injection 

Nozzles 

Remove, clean, and test fuel injection 

nozzles at Direct Support maintenance 

level. See paragraph 4.6.2. 
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Section IV. TROUBLESHOOTING 

3.6. UNIT TROUBLESHOOTING PROCEDURES.

3.6.1 Purpose of Troubleshooting Flowchart.

This section contains troubleshooting information for locating and correcting operating troubles which may develop 

in the engine. Each malfunction for an individual component, unit, or system is followed by a list of tests or 

inspections which will help you to determine probable causes and corrective action to take. You should perform 

tests/inspections and corrective actions in order listed. 

Table 3-2 Unit Troubleshooting, cannot list all malfunctions that can occur, nor all tests or inspections and 

corrective actions. If a malfunction is not listed or cannot be corrected by listed corrective actions, notify your 

supervisor. 

NOTE 

Before you use Table 3-2, be sure you have performed your PMCS. Prior 

to performing troubleshooting procedures within this manual, perform 

troubleshooting procedures in TM 9-6115-672-14 or other applicable TM. 

SYMPTOM INDEX 

 

Malfunction Page 

 Engine Fails to Crank..........................................................................................................................3-4 

 Starter Operates But Engine Does Not Turn Over ..............................................................................3-4 

 Engine Cranks But Fails to Start .........................................................................................................3-5 

 Engine Misfires Or Runs Erratically Or Stalls Frequently ..................................................................3-6 

 Engine Does Not Develop Full Power ................................................................................................3-7 

 Engine Overheating.............................................................................................................................3-8 

 Excessive Oil Consumption.................................................................................................................3-9 

 Low Oil Pressure.................................................................................................................................3-10 

 Excessive Fuel Consumption...............................................................................................................3-11 

 Black or Gray Exhaust Smoke.............................................................................................................3-12 

 Blue or White Exhaust Smoke ............................................................................................................3-12 

 Engine Knocks ....................................................................................................................................3-13 

 Engine Makes Abnormal Noise...........................................................................................................3-13 

 Engine Makes a Hissing of Vapor Leaking Noise...............................................................................3-14 
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TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 1 of 11) 

 Not OK 

 OK Not OK 

 Not OK OK 

ENGINE FAILS TO CRANK

Test for defective starter 

solenoid 

(refer to paragraph 3.9.2).

Replace starting motor 

(refer to paragraph 

3.9.2).

Test for defective starting 

motor 

 (refer to paragraph 3.9.2).

Notify next higher 

level of maintenance.

Notify next higher level 

of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 

9-6115-672-14 or other applicable TM).

Engine fails to crank.

 OK Not OK 

STARTER OPERATES BUT ENGINE 

DOES NOT TURN OVER.

Notify next higher 

level of maintenance.

Remove starter (refer to paragraph 

3.9.2) and check for worn or 

broken starter pinion gear.

Repair or replace starter 

(refer to paragraph 3.9.2).

Verify that engine is not 

seized.

Starter operates but engine 

does not turn over.

Notify next higher 

level of maintenance.

 OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-5 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 2 of 11) 

 Not OK 

 OK Not OK 

ENGINE CRANKS BUT FAILS TO START

Engine cranks but fails to start.

Replace fuel filter (refer 

to paragraph 3.12.2).

Perform end item troubleshooting 

procedures (refer to TM 

9-6115-672-14 or other applicable TM).

Check for clogged or defective fuel 

filter (refer to paragraph 3.12.2).

Bleed fuel lines (refer to paragraph 

3.12.1). Check for evidence of air 

bubbles or fuel line blockage.

Check for defective fuel 

transfer supply pump 

(refer to paragraph 3.12.3).

Unblock or replace fuel 

line(s) (refer to 

paragraph 3.12.4). 

Bleed fuel lines (refer 

to paragraph 3.12.1).

Replace fuel supply pump 

(refer to paragraph 3.12.3).

Notify next higher 

level of 

maintenance.

OK 

 Not OK 

 OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-6 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 3 of 11) 

 Not OK OK 

 OK Not OK 

ENGINE MISFIRES OR RUNS ERRATICALLY OR 

STALLS FREQUENTLY

Engine misfires or runs erratically 

of stalls frequently.

Test fuel transfer supply pump 

(refer to paragraph 3.12.3).

Replace fuel transfer supply 

pump 

(refer to paragraph 3.12.3).

Bleed fuel lines (refer to 

paragraph 3.12.1). Check for 

evidence of air bubbles or fuel 

line obstruction.

Check for low coolant 

temperature (refer to TM 

9-6115-672-14 or other 

applicable TM).

Replace defective 

thermostat (refer to 

paragraph 3.8.2).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Unblock or replace fuel line(s) 

(refer to paragraph 3.12.4). Bleed 

fuel lines (refer to paragraph 

3.12.1).

Notify next higher 

level of maintenance.

 Not OK OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-7 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 4 of 11) 

 Not OK OK 

 OK Not OK 

 Not OK OK 

ENGINE DOES NOT DEVELOP FULL POWER

Engine does not 

develop full power.

Check for restricted air 

filter (refer to TM 

9-6115-672-14 or other 

applicable TM).

Replace air filter elements 

(refer to TM 9-6115-672-14 

or other applicable TM).

Check for restricted 

fuel filter (refer to 

paragraph 3.12.2).

Replace fuel filter 

(refer to paragraph 

3.12.2).

Bleed fuel lines (refer to 

paragraph 3.12.1). Check for 

evidence of air bubbles or fuel 

line obstruction.

Unblock or replace fuel 

line(s) (refer to paragraph 

3.12.4). Bleed fuel lines 

(refer to paragraph 3.12.1).

Notify next higher 

level of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-8 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 5 of 11) 

 Not OK OK 

ENGINE OVERHEATING

Engine overheating.

Check coolant level (refer 

to TM 9-6115-672-14 or 

other applicable TM).

Locate source of coolant leak and 

repair or replace (refer to TM 

9-6115-672-14). Add coolant (refer 

to TM 9-6115-672-14 or other 

applicable TM).

Check for defective 

thermostat (refer to 

paragraph 3.8.2).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Replace thermostat 

(refer to paragraph 

3.8.2).

Check for defective 

water pump (refer 

to paragraph 3.8.3).

Replace defective 

water pump (refer 

to paragraph 3.8.3).

Notify next higher 

level of 

maintenance.

 OK Not OK 

 OK Not OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-9 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 6 of 11) 

 OK 

 OK Not OK 

EXCESSIVE OIL CONSUMPTION

Excessive oil consumption.

Measure engine blowby 

(refer to Paragraph 3.7.2).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicabe TM).

Visually inspect for 

external oil leaks.

Notify next higher level 

of maintenance.

Notify next higher level 

of maintenance.

 Not OK 

Test for low engine 

compression 

(refer to paragraph 3.7.1).

Notify next higher level 

of maintenance.

Notify next higher level 

of maintenance.

 Not OK OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-10 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 7 of 11) 

 Not OK OK 

 Not OK OK 

LOW OIL PRESSURE

Low oil pressure.

Check for proper lube oil 

type (refer to TM 

9-6115-672-14 or other 

applicable TM).

Drain oil and replace oil filter 

(refer to paragraph 3.11.2). 

Refill with proper lube oil type 

(refer to TM 9-6115-672-14 or 

other applicable TM).

Refer to troubleshooting 

section labeled "ENGINE 

OVERHEATING".

Check for engine 

overheating (refer to TM 

9-6115-672-14 or other 

applicable TM).

Notify next higher 

level of 

maintenance.

Perform end item 

troubleshooting procedures 

(refer to TM 9-6115-672-14 or 

other applicable TM).
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-11 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 8 of 11) 

 OK Not OK 

EXCESSIVE FUEL CONSUMPTION

Excessive fuel consumption.

Check for leaks in fuel 

system (refer to paragraph 

3.12.4).

Repair fuel system as 

required.

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Notify next higher 

level of 

maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-12 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 9 of 11) 

 Not OK OK 

 OK Not OK 

BLACK OR GRAY EXHAUST SMOKE

Black or gray 

exhaust smoke.

Check for restricted air filter 

(refer to TM 9-6115-672-14 

or other applicable TM).

Replace air filter elements 

(refer to TM 9-6115-672-14 or 

other applicable TM).

Check for defective fuel 

injection pump (refer to 

paragraph 3.12.5).

Notify next higher 

level of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 

or other applicable TM).

 Not OK OK 

BLUE OR WHITE EXHAUST SMOKE

Blue or white exhaust smoke.

Check for restricted air filter (refer to 

TM 9-6115-672-14 or other 

applicable TM).

Replace air filter elements 

(refer to TM 9-6115-672-14 

or other applicable TM).

Notify next higher 

level of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

othe applicable TM).

Notify next higher 

level of maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-13 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 10 of 11) 

ENGINE KNOCKS

Engine knocks.

Check for dirty, defective, or 

leaking fuel injection nozzles 

(refer to paragraph 3.12.6).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Notify next higher level 

of maintenance.

OK Not OK

 OK Not OK 

 Not OK OK 

Abnormal engine noise.

Check for worn or damaged 

water pump bearing 

 (refer to paragraph 3.8.3).

Replace water pump 

(refer to paragraph 

3.8.3).

Check for damaged battery 

charging alternator 

 (refer to paragraph 3.9.1).

Repair or replace 

battery charging 

alternator (refer to 

paragraph 3.9.1).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Notify next higher level 

of maintenance.

ABNORMAL ENGINE NOISE

Notify next higher level

of maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-14 

 

TABLE 3-2. UNIT TROUBLESHOOTING 

(Sheet 11 of 11) 

 OK Not OK 

 Not OK OK 

ENGINE MAKES A HISSING OR 

VAPOR LEAKING NOISE

Engine makes a hissing or vapor leaking noise.

Check for loose or damaged 

exhaust manifold 

(refer to paragraph 3.10.2).

Notify next higher 

level of maintenance.

Check for loose fuel 

injection nozzles (refer to 

paragraph 3.12.6).

Notify next higher 

level of 

maintenance.

 Not OK OK Check for evidence of gas 

leakage around cylinder 

head gasket.

Notify next higher 

level of maintenance.

Notify next higher level 

of maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-15 

Section V. MAINTENANCE PROCEDURES 

3.7. GENERAL.

 This section provides general maintenance not found in other sections of Chapter 3. 

__________ 

WARNING

 

Where applicable, prior to performing engine maintenance, ensure 

batteries are disconnected to prevent serious injury or death. 

__________ 

WARNING

Service tools are designed to aid disassembly and assembly procedures. 

Service tools must be used to prevent possible damage to components. Some 

operations can cause personal injury if carried out without use of relevant 

tools. 

NOTE 

Refer to TM 9-6115-672-14 for removal of any components necessary to 

gain access to engine. 

a. All bolts or nuts securing cylinder heads, covers, and doors must be tightened in proper sequence. 

b. When assembling an engine, always replace nuts, bolts, and lockwashers that have been removed from high 

stress locations such as from connecting rods and cylinder heads. 

c. When assembling an engine always apply a small quantity of new engine lubricating oil (MIL-L-2104) to 

all moving parts. 

d. After any maintenance work on engine has been completed lubricating oil and fuel levels must be checked 

and all safety guards installed before operating. 

e. When a new fan drive belt has been installed, check belt tension after first 20 hours of operation. 

f. Wear protective overalls, and keep items of loose clothing clear of all hot and moving parts. Use protective 

barrier cream when necessary. 

g. Clean components and surrounding area before removing or disassembling. All dirt and debris must be 

excluded from fuel injection equipment while it is being serviced. 

h. Some parts are cemented with gasket compound. Before assembly, remove all traces of old gasket and 

compound. All gaskets and gasket compound must be excluded from tapped holes unless otherwise 

specified. 

i. All oil seals removed from their original position must be replaced. Seals must be installed square in 

housing and all lip seals must be installed with lip facing lubricant to be retained. Use service tool to install 

oil seals. Care must be taken to prevent damaging new seal when it passes over shafts. 

j. Replace all nuts, bolts, capscrews, and studs with damaged threads. Do not use tap or die to repair 

damaged threads which may impair the strength and/or closeness of the threads. 
ARMY TM 9-2815-260-24 

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3-16 

k. Do not allow grease or oil to enter a blind threaded hole. Hydraulic action present when bolt or stud is 

tightened could split or stress housing. 

l. Bolts or nuts must be loosened one quarter turn and then tightened to specified value to check or re-torque. 

m. Steel ISO metric bolt and nuts can be identified by the letter M either on head or on one hexagon flat. The 

strength grade will also be marked on top or on one flat. 

n. Nuts with identification marks on face will reduce frictional area of surface. Nuts with identification marks 

on one face must be installed with unmarked face towards component. 

o. Cover or cap all openings to prevent entry of foreign material when removing or disconnecting fuel lines, 

lubrication lines, or coolant hoses. Remove covers and caps upon installation. 

3.7.1. TEST ENGINE COMPRESSION PRESSURE.

NOTE 

Before beginning test, ensure that batteries are fully charged and injection 

nozzle area is thoroughly cleaned. 

a. Run engine to bring up to normal operating temperature. (From a cold start, operate engine 10 to 15 

minutes then shut off engine). 

b. Shut off fuel supply and remove fuel injection nozzles, refer to paragraph 4.6.2. 

c. Install adapter (JT01679) with O-ring in injection nozzle bore. Use holding clamp (JT02017) to hold 

adapter in position. Install hold down screw in clamp and tighten screw to 27 lb-ft (37 Nm). Attach test 

gage (JT01682) to adapter. Refer to Appendix B, Section III. 

d. Refer to TM 9-6115-672-14, and using DEAD CRANK switch, (or other applicable device), turn 

crankshaft for 10 to 15 seconds with starter (150 rpm minimum cranking speed). Record pressure reading. 

e. Compare readings from all cylinders. 

f. Compression pressure must be 350 psi (2400 kPa) minimum. The difference between the highest and 

lowest cylinder must be less than 50 psi (340 kPa). 

g. If pressure is much lower than shown, remove gage and apply oil to ring area of piston through injection 

nozzle bore. Do not use too much oil. Do not get oil on the valves. 

h. Test compression again. If pressure is still low, it is possible that valves are worn or sticking, or o-rings are 

worn or stuck. 

3.7.2. MEASURE ENGINE BLOW-BY.

a. Place a hose with a standard gas gage in end of crankcase vent tube. 

b. Run engine at rated speed and load (engine at operating temperature and run-in, with at least 100 operating 

hours). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-17 

c. Measure blow-by over a period of 5 minutes. Multiply figure obtained by 12 (hourly rate). Maximum 

allowable blow-by is 600 cu ft/h (17 m3/h). 

d. If blow-by is lower, there probably is no undue wear between piston rings and liners. If blow-by is higher, 

there could be excessive wear between piston rings and liners, resulting in loss of engine power. 

3.7.3 INTAKE MANIFOLD PRESSURE CHECK.

a. Remove plug (6, Figure 3-7) from intake manifold and connect suitable gage to intake manifold. 

b. Run engine to bring up to normal operating temperature. (From a cold start, operate engine 10 to 15 

minutes). 

NOTES 

Engine speed and load should be stabilized before taking readings on gage. 

Be sure that gage works properly. 

Pressure checks are only a guide to determine if there is an engine problem 

(valve leakage, defective nozzles, etc.). Low readings are not a valid reason 

for increasing injection pump fuel delivery. Pump adjustment should be 

within specification. 

c. Observe pressure reading on gage. Reading should be at least 9 psi (60 kPa)/0.6 bar) when engine is 

developing rated power at full load rated speed. Shut down engine. 

d. If boost pressure is too high, remove and test fuel injection pump for high fuel delivery. 

e. If boost pressure is too low, check for the following: 

 (1) Restricted air filter elements. Refer to TM 9-6115-672-14. 

 (2) Restricted fuel filter elements. Refer to TM 9-6115-672-14. 

 (3) Incorrect injection pump timing. Refer to paragraph 5.3.1. 

 (4) Exhaust manifold leaks. Refer to paragraph 3.10.2. 

 (5) Intake manifold leaks. Refer to paragraph 3.10.1. 

 (6) Faulty fuel transfer pump. Refer to paragraph 3.12.3. 

 (7) Low compression pressure. Refer to paragraph 3.7.1. 

 (8) Faulty fuel injection nozzles. Notify next higher level of maintenance, refer to paragraph 4.6.2. 

 (9) Carbon build-up in turbocharger. Notify next higher level of maintenance, refer to paragraph 

4.4.1. 

 (10) Turbocharger compressor or turbine wheel rubbing housing. Notify next higher level of 

maintenance, refer to paragraph 4.4.1. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

3-18 

 (11) Low fuel injection pump fuel delivery. Notify general support maintenance, refer to paragraph 

5.4.12. 

 (12) Restricted exhaust. Refer to TM 9-6115-672-14. 

f. Remove test gage and install plug (6, Figure 3-7) in intake manifold. 

3.8. COOLING SYSTEM MAINTENANCE.

3.8.1. GENERAL.

This section provides maintenance for cooling system components. Components of cooling system not 

mentioned in this section can be found in the TM 9-6115-672-14. 

__________ 

WARNING

Engine coolant is very hot and under pressure after engine has been 

operating. Allow engine to cool before you slowly loosen filler cap and 

relieve pressure from cooling system. Failure to comply could result in 

severe personal injury. 

3.8.2. THERMOSTAT AND WATER MANIFOLD/THERMOSTAT COVER.

a. Removal.

__________ 

WARNING

Engine coolant is very hot and under pressure after engine has been 

operating. Allow engine to cool before you slowly loosen filler cap and 

relieve pressure from cooling system. Failure to comply could result in 

severe personal injury. 

(1) Drain coolant system if not already drained, refer to TM 9-6115-672-14. 

NOTE 

Remove fan guards if needed. 

(2) Disconnect coolant outlet hose from water manifold/thermostat housing (8, Figure 3-1), refer to 

TM 9-6115-672-14. 

(3) Remove capscrew (1, Figure 3-1) and move clamp (3) clear of cylinder head and alternator 

bracket. 

(4) Disconnect water pump tube (4) and remove seal (5). Seal can be accessed by removing water 

temperature sender (refer to TM 9-6115-672-14). Discard seal. 

(5) Remove capscrews (6 and 7), from water manifold/thermostat housing (8), thermostat (9), and 

gasket (10). Discard gasket. 

(6) Disconnect plug (11). 

(7) Cover all openings to prevent entry of foreign material. 
ARMY TM 9-2815-260-24 

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3-19 

b. Inspection.

(1) Remove thermostat (9, Figure 3-1), refer to step a. 

 (2) Inspect thermostat (9) for excessive wear or damage. 

 (3) Remove plug (11) and O-ring seal (12). 

 (4) Inspect water manifold / thermostat cover (8) for cracks, corrosion, or other damage. 

 (5) Inspect water temperature sender (15) if installed. 

FIGURE 3-1. THERMOSTAT AND WATER MANIFOLD/THERMOSTAT COVER. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

3-20 

c. Replacement.

NOTE 

Replace thermostat if suspected of being defective. 

 (1) Remove thermostat and water manifold/thermostat cover, refer to step a. 

(2) Inspect thermostat and water manifold/thermostat cover, refer to step b. Replace parts found 

defective. 

(3) Position new O-ring seal (12, Figure 3-1) on water manifold / thermostat cover and install plug 

(11). 

 (4) Install thermostat (9), refer to step d. 

d. Installation.

 (1) Remove all covering installed during step a (6). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Lubricate seal (5) with multi-purpose grease. Install seal. 

(4) Install guide studs (1, Figure 3-2) if needed, in place of capscrews (6 and 7, Figure 3-1) and 

position gasket (10, Figure 3-1) on cylinder head. 

 (5) Connect water temperature sending unit (15). 

(6) Position thermostat (9, Figure 3-1) and water manifold / thermostat cover (8) on cylinder head 

using a screwdriver (2, Figure 3-2) to hold thermostat in place, refer to Figure 3-2. 

NOTE 

Remove one guide stud, if used, and install one capscrew before removing 

second guide stud. 

(7) Remove guide studs, if used, and install capscrews (6 and 7, Figure 3-1). Torque capscrews 

evenly to 52 lb-ft (70 Nm). 

 (8) Install water pump tube (4). 

 (9) Position clamps (3) on cylinder head and alternator bracket and install capscrews (1 and 2). 

(10) Connect coolant outlet hose, refer to TM 9-6115-672-14. 

NOTE 

Air must be expelled from system when refilled with coolant. Loosen plug 

in thermostat housing to allow air to escape when filling system. Retighten 

plug when all air has been expelled. 

 (11) Service coolant system, refer to TM 9-6115-672-14. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-21 

FIGURE 3-2. THERMOSTAT INSTALLATION. 

3.8.3. WATER PUMP.

a. Removal.

__________ 

WARNING

Engine coolant is very hot and under pressure after engine has been 

operating. Allow engine to cool before you slowly loosen filler cap and 

relieve pressure from cooling system. Failure to comply could result in 

severe personal injury. 

 (1) Drain coolant system if not already drained. Refer to TM 9-6115-672-14. 

 (2) Remove fan shroud, fan, and fan belt, refer to TM 9-6115-672-14. 

 (3) Disconnect lower inlet coolant hose from inlet elbow (3, Figure 3-3), refer to TM 9-6115-672-14. 

 (4) Remove capscrews (1 and 2), inlet elbow (3), and O-ring seal (4). Discard O-ring seal. 

(5) Remove capscrews (1 and 2, Figure 3-1) and move clamps (3) clear of cylinder head and 

alternator bracket. 

 (6) Disconnect water pump tube (4, Figure 3-1) from water pump (8, Figure 3-3). 

 (7) Remove and discard seal (5, Figure 3-3). 

(8) Remove capscrews (10) and pulley (11). 

 

(9) Remove short capscrews (6), long capscrews (7), water pump (8), and gasket (9). Discard gasket. 

 

 (10) Remove plug (12) and O-ring seal (13). Discard O-ring seal. 

 (11) Cover all openings to prevent entry of foreign material. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-22 

FIGURE 3-3. WATER PUMP ASSEMBLY. 

b. Inspection.

 (1) Remove water pump (8, Figure 3-3), refer to step a. 

 (2) Inspect water pump (8) rotation for abnormal noise, binding, or other abnormal conditions. 

 (3) Inspect water pump (8) housing for cracks, corrosion, or any other damage. 

c. Replacement.

 (1) Remove water pump (8, Figure 3-3), refer to step a. 

(2) Inspect water pump (8), refer to step b. Replace water pump if inspection reveals cracks, 

corrosion, or any other damage. For installation of water pump (8), refer to step d. 

d. Installation.

 (1) Remove all covering installed during step a (11). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Position new O-ring seal (13, Figure 3-3) on water pump (8). Install plug. 

(4) Lubricate new seal (5) with multi-purpose grease. Install seal and water pump tube (4, Figure 3-

1). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-23 

(5) Position new gasket (9) and water pump (8) on timing gear cover. Install short capscrews (6), and 

long capscrews (7), and torque evenly to 12 lb-ft (16 Nm). 

(6) Position pulley (11) on water pump (8). Install capscrews (10) and torque evenly to 12 lb-ft (16 

Nm). 

(7) Position new O-ring seal (4, Figure 3-3) and inlet elbow (3) on water pump (8). Install capscrews 

(1 and 2) and torque evenly to 26 lb-ft (35 Nm). 

(8) Install capscrews (1 and 2, figure 3-1) clamps (3), water pump tube (4) and new seal (5). 

 (9) Connect coolant inlet hose, refer to TM 9-6115-672-14. 

 (10) Install fan shroud, fan, and fan belt, refer to TM 9-6115-672-14. 

NOTE 

Air must be expelled from system when refilled with coolant. Loosen plug 

in thermostat housing to allow air to escape when filling system. Retighten 

plug when all air has been expelled. 

 (11) Service coolant system, refer to TM 9-6115-672-14. 

3.9. ELECTRICAL SYSTEM MAINTENANCE.

3.9.1. BATTERY CHARGING ALTERNATOR.

a. Test, Battery charging alternator (installed).

(1) Check for battery voltage at alternator, between terminals B+ (7, Figure 3-4) and ground (8). Note 

voltage. Voltage should be between 0 and 24 VDC. Minimum required voltage for start up is 18 

VDC. 

(2) Start and operate generator. Refer to TM 9-6115-672-14. Recheck voltage on alternator terminal 

B+ and ground (8) for 28 +/- 2 VDC. 

b. Removal.

 (1) Tag and disconnect electrical leads from battery charging alternator. 

 (2) Remove fan belt, refer to TM 9-6115-672-14. 

 (3) Remove capscrew (1, Figure 3-4) and washer (2). 

(4) Support weight of battery charging alternator and remove capscrew (3), washer (4), nut (5) and 

alternator (6). Remove alternator (6). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-24 

FIGURE 3-4. BATTERY CHARGING ALTERNATOR MOUNTING. 

c. Inspection.

(1) Inspect rear housing for cracked or broken casting, stripped threads and severe wear of the bearing 

bore. 

(2) Inspect fan for cracked or broken fins and for worn mounting hole. 

(3) Inspect front housing for cracked or broken casting, stripped threads and bore of mounting foot for 

elongation. 

(4) Inspect other components for damage such as broken terminals or insulation, discoloration, 

stripped threads and other obvious damage. 

d. Replacement.

 (1) Test battery charging alternator (6, Figure 3-4), refer to paragraph 3.9.1.a. 

 (2) Remove battery charging alternator (6) from engine, refer to paragraph 3.9.1.b. 

(3) Inspect battery charging alternator (6), refer to paragraph 3.9.1.c. Replace if inspection reveals 

defective. For installation of battery charging alternator, refer to paragraph 3.9.1.e. 

 (4) Send removed alternator to next higher maintenance level for repair. 
ARMY TM 9-2815-260-24 

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3-25 

e. Installation.

(1) Position battery charging alternator (6, Figure 3-4) on mounting bracket and install capscrew (3), 

washer (4) and nut (5). 

 (2) Install washer (2) and capscrew (1). 

(3) Connect electrical leads to battery charging alternator (6) as tagged during removal. Refer to 

paragraph 3.9.1.a. 

(4) Install fan belts on battery charging alternator (6), refer to TM 9-6115-672-14. 

3.9.2. STARTER.

a. Test (Installed on Generator).

(1) Make sure batteries are fully charged and that all battery and starter cables are serviceable and 

properly installed. 

(2) Set multimeter for DC volts and connect as shown in Figure 3-5, Test A. If voltage is indicated 

solenoid is defective. 

(3) Momentarily connect a jumper as shown in Figure 3-5, Test B. Multimeter should indicate battery 

voltage and starter should crank the engine. If multimeter does not read battery voltage, the 

solenoid is defective and must be replaced. If multimeter indicates battery voltage, but starter 

does not operate, starter is defective and must be replaced. 

FIGURE 3-5. STARTER SOLENOID TEST CIRCUIT. 
ARMY TM 9-2815-260-24 

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b. Removal.

 (1) Ensure generator set negative battery terminal connection is disconnected from battery. 

 (2) Tag and disconnect electrical leads from starter. 

(3) Support weight of starter and remove two screws (1, Figure 3-6), lockwashers (2) and washers (3) 

securing starter to flywheel housing. Remove starter. 

 (4) Cover opening in flywheel housing. 

c. Inspection.

 (1) Inspect housing for cracked or broken casting and stripped threads or missing insulation. 

 (2) Inspect pinion (19, Figure 3-6) for chipped or worn teeth. 

d. Replacement.

 (1) Test starter installed on generator, refer to paragraph 3.9.2.a. 

 (2) Remove starter, refer to paragraph 3.9.2.b. 

(3) Inspect starter, refer to paragraph 3.9.2.c. Replace starter if solenoid or starter is found defective 

during test in step a. Starter must also be replaced if inspection reveals faulty components. For 

installation of starter, refer to paragraph 3.9.2.e. 

 (4) Send removed starter to next higher maintenance level for repair. 

e. Installation.

 (1) Remove cover in opening of flywheel housing. 

(2) Place gasket (4, Figure 3-6), and starter on flywheel housing and secure with two screws (1), new 

lockwashers (2) and washers (3). Tighten screws to 30 - 35 lb-ft (41 - 47 Nm). 

 (3) Connect electrical leads to starter as tagged during removal. 

 (4) Reconnect negative battery terminal. 
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FIGURE 3-6. STARTER ASSEMBLY 
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3.10. INTAKE AND EXHAUST SYSTEM MAINTENANCE.

__________ 

WARNING

Exhaust system is very hot after operating engine. After operating engine, 

allow exhaust system to cool before removal. Failure to comply could result 

in personal injury. 

3.10.1. INTAKE MANIFOLD.

a. Inspection.

Inspect intake manifold (4, Figure 3-7) for serviceability. Notify next higher maintenance level if cracked 

or otherwise damaged. 

FIGURE 3-7. INTAKE MANIFOLD. 
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3.10.2. EXHAUST MANIFOLD.

a. Inspection.

Inspect exhaust manifold (2, Figure 3-8) for serviceability. Notify next higher maintenance level if cracked 

or otherwise damaged. 

FIGURE 3-8. EXHAUST MANIFOLD. 

3.11. LUBRICATION SYSTEM MAINTENANCE.

3.11.1. GENERAL.

 This section provides maintenance for lubrication system components. 

3.11.2. OIL FILTER ASSEMBLY.

a. Removal.

 (1) Drain engine lubrication system, refer to TM 9-6115-672-14. 

 (2) Remove oil filter (1, Figure 3-9). 

 (3) Disconnect turbocharger oil inlet line from fitting (2). Remove fitting. 

(4) Remove capscrews (3, 4, 5, and 6). Gently remove oil filter head (7) and oil filter adapter (8) 

together at the same time. Remove and discard gasket (9). 

 (5) Disconnect oil filter head (7) from tubes (10 and 11). 

 (6) Remove tubes (10 and 11) and O-ring seals (12). Discard O-ring seals. 

 (7) Remove plugs (13). 

 (8) Cover all openings to prevent entry of foreign material. 

b. Inspection.

 (1) Remove oil filter assembly, refer to step a. 

(2) Inspect oil filter head (7, Figure 3-9), oil filter adapter (8), and tubes (10 and 11) for cracks or 

other damage. 
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c. Replacement.

 (1) Remove oil filter assembly, refer to step a. 

(2) Inspect oil filter assembly, refer to step b. Replace oil filter head (7, Figure 3-9), oil filter adapter 

(8), or tubes (10 and 11) if inspection reveals cracks, corrosion, or any other damage. For 

installation of oil filter assembly, refer to step d. 

 (3) For servicing of engine lubrication system, refer to TM 9-6115-672-14. 

d. Installation.

 (1) Remove all covering installed during step a (8). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Install plugs (13, Figure 3-9). 

FIGURE 3-9. OIL FILTER ASSEMBLY. 
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 (4) Position O-ring seals (12) and tubes (10 and 11) on oil filter adapter (8). 

 (5) Position o-ring seals (12) and oil filter head (7) on tubes (10 and 11). 

(6) Position gasket (9), oil filter head (7) and oil filter adapter (8) together into proper position on 

cylinder block and oil cooler housing. Install capscrews (3, 4, 5, and 6) and torque to 26 lb-ft 

(35.9 Nm). 

 (7) Install fitting (2). Connect turbocharger oil inlet line. 

 (8) Install oil filter (1). 

 (9) Service engine lubrication system, refer to TM 9-6115-672-14. 

3.11.3. OIL COOLER.

a. Removal.

__________ 

WARNING

Engine coolant is very hot and under pressure after engine has been 

operating. Allow engine to cool before you slowly loosen filler cap and 

relieve pressure from cooling system. Failure to comply could result in 

severe personal injury. 

 (1) Allow engine to cool and drain coolant system, refer to TM 9-6115-672-14. 

(2) Remove oil filter assembly, refer to paragraph 3.11.2, step a. 

(3) Remove drain plug (1, Figure 3-10) and plug (2). 

(4) Remove capscrews (3 and 4), adapter (5), gasket (6) and O-ring seal (7). Discard gasket and Oring seal. 

(5) Remove oil cooler housing (8) and gasket (9). Discard gasket. 

(6) Remove capscrews (10) and oil cooler (11). 

(7) Remove O-ring seals (12) and discard. 

(8) Cover all openings to prevent entry of foreign material. 

b. Inspection.

(1) Remove oil cooler (11, Figure 3-10), refer to step a. 

(2) Inspect oil cooler (11) for physical damage, plugging, or leakage which may allow mixing of oil 

and coolant. 

(3) Back flush oil cooler (11) to clean all debris from core. 
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(4) Pressure test oil cooler (11) in liquid with compressed air if mixing of oil and coolant is suspected. 

Oil cooler should show no leakage when 20-25 psi (140-170 kPa) of air pressure is applied for a 

minimum of 30 seconds. If leakage exists, oil cooler must be replaced. 

(5) Inspect oil cooler housing (8) and adapter (5) for physical damage, plugging, or leakage. Replace 

parts as needed. 

FIGURE 3-10. OIL COOLER ASSEMBLY. 

c. Replacement.

(1) Remove oil cooler (11, Figure 3-10), refer to step a. 

(2) Inspect oil cooler assembly, refer to step b. Replace components if physically damaged or leaks 

are detected during inspection. 

 (3) Install oil cooler (11), refer to step d. 
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d. Installation.

(1) Remove all covering installed during step a (8). 

(2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Install plug (2) and drain plug (1) and torque evenly to 26 lb-ft (35 Nm). 

(4) Position O-ring seals (12, Figure 3-10) on oil cooler (11) and lubricate with clean engine oil. 

(5) Apply Thread Lock and Sealer (LOCTITE 242) to capscrews (10). 

 (6) Position oil cooler (11) in oil cooler housing (8). Install capscrews (10) and torque evenly to 9 lbft (12 Nm). 

(7) Position O-ring seal (7) in adapter (5). 

(8) Position gasket (9), oil cooler housing (8), gasket (6) and adapter (5) on engine block. Install 

capscrews (3 and 4) and torque evenly to 26 lb-ft (35 Nm). 

 (9) Install oil filter assembly, refer to paragraph 3.11.2, step c. 

3.11.4. OIL FILL TUBE.

a. Removal.

 (1) Remove oil fill cap (1, Figure 3-11), capscrews (2), oil fill tube (3) and gasket (4). Discard gasket. 

(2) Cover all openings to prevent entry of foreign material. 

FIGURE 3-11. OIL FILL TUBE ASSEMBLY. 
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b. Inspection.

Inspect oil fill tube (3, Figure 3-11) and oil fill cap (1) for cracks or other damage. 

c. Replacement.

 (1) Remove oil fill tube, refer to step a. 

(2) Inspect oil fill tube (3, Figure 3-11) and cap (1), refer to step b. Replace oil fill tube or oil fill cap 

if found defective. For installation, refer to step d. 

d. Installation.

(1) Remove all covering installed during step a (2). 

(2) Ensure all old gasket material is removed from gasket surfaces. 

(3) Apply Thread Lock and Sealer (LOCTITE 242) to threads of capscrews (2). 

(4) Position gasket (4) and oil fill tube (3) on engine block. Install capscrews (2) and torque evenly to 

26 lb-ft (35 Nm). 

(5) Install oil fill cap (1) 

3.11.5. OIL DIPSTICK TUBE.

a. Inspection.

Visually inspect oil dipstick (1, Figure 3-12) and oil dipstick tube (2) for cracks, dents, or other damage. 

Remove and replace if found defective. 

FIGURE 3-12. OIL DIPSTICK TUBE ASSEMBLY. 
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b. Removal.

(1) Remove oil dipstick (1, Figure 3-12). 

NOTE 

Note position of dipstick tube to ensure proper position during installation. 

 (2) Remove dipstick tube (2). 

(3) Cover all openings to prevent entry of foreign material. 

c. Replacement.

 (1) Inspect oil dipstick (1, Figure 3-12) and oil dipstick tube (2), refer to step a. 

(2) Remove oil dipstick (1) and oil dipstick tube (2), refer to step b. Replace if damaged. For 

installation, refer to step d. 

d. Installation.

(1) Remove all covering installed during step b (3). 

(2) Coat end of dipstick tube (2, Figure 3-12) with Retaining Compound (LOCTITE 680). 

 (3) Install dipstick tube until dipstick tube shoulder bottoms against engine block. 

(4) Install dipstick. 

FIGURE 3-13. OIL DIPSTICK TUBE INSTALLATION. 
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3.11.6. OIL PAN.

a. Inspection.

(1) Inspect oil pan (2, Figure 3-14) for cracks, dents, or other damage. Notify next higher 

maintenance level if oil pan is cracked, dented, or damaged. 

(2) Inspect gasket (1) for signs of leakage. Notify next higher maintenance level if oil pan gasket 

shows signs of leakage. 

(3) Inspect plugs (5) and hole for damaged threads or signs of leakage. Notify next higher 

maintenance level if oil plugs (5) or hole shows signs of leakage. 

FIGURE 3-14. OIL PAN. 

3.12. FUEL SYSTEM MAINTENANCE.

__________ 

WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to 

penetrate the skin, causing serious injury or death. Before disconnecting 

fuel lines, be sure to relieve pressure. Before applying pressure to the 

system, be sure all connections are tight and lines, pipes, and hoses are not 

damaged. Keep hands and body away from pinholes and nozzles which 

eject fuel under pressure. Use a piece of cardboard or wood, rather than 

hands, to search for suspected leaks. 
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__________ 

WARNING

If diesel or JP fuel is injected into skin, seek medical attention immediately. 

Failure to comply can result in serious injury. 

3.12.1. BLEEDING FUEL SYSTEM.

a. General.

Any time fuel system has been opened up for service (lines disconnected or filter removed), it will be 

necessary to bleed air from system. The fuel system can be bled at one of several locations. 

NOTE 

The top panel may have to be removed to access the fuel lines.

b. Bleed at Fuel Filter.

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

NOTE 

Catch fuel in suitable container. 

 (1) Open air bleed vent screw (14, Figure 3-15) two full turns. 

(2) Pump primer lever (6, Figure 3-16) on fuel supply pump until a noticeable amount of fuel and air 

comes out of air bleed vent screw (14, Figure 3-15) opening. Continue pumping primer lever and 

close air bleed vent screw when fuel starts to flow out air bleed vent screw opening and is free of 

air bubbles. 

(3) Pump primer lever (6, Figure 3-16) several times until resistance is felt. Continue pumping primer 

lever and open air bleed vent screw (14, Figure 3-15) again momentarily. 

(4) Close air bleed vent screw (14, Figure 3-15) and pump primer lever (6, Figure 3-16) several times 

until resistance is felt again. Push primer lever downward and release. 
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c. Bleed at Fuel Injection Pump.

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

NOTE 

Catch fuel in suitable container. 

 (1) Loosen fuel return line (3, Figure 3-17) at fuel injection pump. 

 (2) Pump primer lever (6, Figure 3-16) on fuel supply pump until fuel flow is free from air bubbles. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (3) Tighten fuel return line to 12 lb-ft (16 Nm). 

d. Bleed at Fuel Injection Nozzles.

__________ 

WARNING

Exhaust system is very hot after operating engine. After operating engine, 

allow exhaust system to cool before removal. Failure to comply could result 

in personal injury. 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 
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CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

FIGURE 3-15. FUEL FILTER ASSEMBLY. 
ARMY TM 9-2815-260-24 

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 (1) Loosen connections at all of the fuel injection nozzles. 

__________ 

WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to 

penetrate skin. Place a clear, protective shield around spray zone. Failure 

to comply could result in serious injury or death. 

CAUTION

Damage to fuel injection pump, battery, or starter motor can occur if 

starter motor is used excessively to eliminate air from the fuel system. 

Allow at least two minutes for cooling and battery recovery before 

operating again. 

(2) Using an assistant, operate starter motor (but do not start engine), refer to TM 9-6115-672-14, and 

observe connections until fuel, free from air, comes from high-pressure connections. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (3) Tighten connections to 20 lb-ft (27 Nm). 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

 (4) Thoroughly clean engine and surrounding area to remove spilled diesel fuel. 

FIGURE 3-16. FUEL SUPPLY PUMP. 
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FIGURE 3-17. FUEL INJECTION ASSEMBLY 
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3.12.2. FUEL FILTER.

a. Remove Fuel Filter Element. 

CAUTION

Dirt in the fuel system can damage components or cause poor engine 

performance. Always thoroughly clean the area around connection before 

disconnecting. Always cover all openings after disconnecting. Failure to 

comply can cause damage to components or poor engine performance. 

 (1) Thoroughly clean outside surface of the fuel filter and surrounding area. 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

NOTE 

Catch fuel in suitable container. Dispose of fuel in accordance with local 

ordinances. 

(2) Loosen drain plug (3, Figure 3-15) and allow water and fuel to drain into suitable container. 

NOTE 

Lift up on retaining ring while rotating to ease removal. 

(3) Firmly grasp retaining ring (1) and rotate retaining ring counterclockwise 1/4 turn. Remove 

retaining ring and fuel filter element (2). 

b. Service.

(1) Remove drain plug (3, Figure 3-15) and O-ring seal (4). Discard fuel filter element and O-ring 

seal in a safe place in accordance with local regulations. 

(2) Inspect fuel filter base (9) for cleanliness. Clean as required. 

 (3) Thoroughly inspect seal ring (5) for cracks and other damage. Replace as needed. 

c. Installation 

(1) Position O-ring seal (4, Figure 3-15) on drain plug (3) and install drain plug (3) on new fuel filter 

element (2). 

NOTE 

Fuel filter element must be indexed properly and key on fuel filter element 

must be oriented in slot of fuel filter base for correct installation. 
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(2) Position new fuel filter element (2) on fuel filter base (9) using a slight rocking motion. Insure 

that fuel filter element is properly indexed on fuel filter base. 

 

(3) Position retaining ring (1) on fuel filter base (9) and tighten about 1/3 turn until retaining ring 

"snaps" into detent. Do not overtighten retaining ring. 

 (4) Bleed fuel system, refer to paragraph 3.12.1. 

3.12.3. FUEL TRANSFER SUPPLY PUMP.

a. Test, on Engine.

CAUTION

Dirt in the fuel system can damage components or cause poor engine 

performance. Always thoroughly clean the area around connection before 

disconnecting. Always cover all openings after disconnecting. Failure to 

comply can cause damage to components or poor engine performance. 

 (1) Thoroughly clean outside surface of fuel filter and surrounding area. 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________ 

WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to 

penetrate skin. Before removing plug, be sure to relieve pressure. Failure 

to comply could result in serious injury or death. 

NOTE 

Catch fuel in suitable container. Dispose of fuel in accordance with local 

ordinances. 

(2) Slowly loosen plug (11, Figure 3-15) and allow fuel pressure to dissipate. Remove plug (11) from 

fuel filter and install fuel pressure gage. 

__________ 

WARNING

Operating the generator set with any access door open exposes personnel to 

high noise levels. Hearing protection must be worn when operating or 

working near the generator set with any access door open. Failure to 

comply can cause hearing damage or loss. 

(3) Start engine, refer to TM 9-6115-672-14. Fuel supply pump should maintain positive minimum 

pressure of 2-4 psi (15-30 kPa). 
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(a) If pressure is low, replace filter element, refer to paragraph 3.12.2, and test pressure 

again. 

 (b) If pressure is still low, bench test fuel supply pump, refer to step d. 

 (4) Remove fuel pressure gage and install plug (11). 

 (5) Bleed fuel system, refer to paragraph 3.12.1. 

b. Removal.

CAUTION

Dirt in the fuel system can damage components or cause poor engine 

performance. Always thoroughly clean the area around connection before 

disconnecting. Always cover all openings after disconnecting. Failure to 

comply can cause damage to components or poor engine performance. 

 (1) Thoroughly clean outside surface of fuel supply pump and surrounding area. 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________ 

WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to 

penetrate skin. Before disconnecting lines, be sure to relieve pressure. 

Failure to comply could result in serious injury or death. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

NOTE 

Catch fuel in suitable container. Dispose of fuel in accordance with local 

ordinances. 

(2) Disconnect fuel supply line, connected to fuel inlet (7, Figure 3-16). Slowly loosen fuel line (6, 

Figure 3-15) and allow fuel pressure to dissipate. Remove fuel line. 

(3) Remove capscrews (1, Figure 3-16), flat washers (2), fuel supply pump (3) and o-ring (4). 

Discard o-ring. 

 (4) Inspect all removed sealing washers and fittings. If damaged, replace. 
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 (5) Cover all openings to prevent entry of foreign material. 

c. Inspection.

 (1) Remove fuel supply pump, refer to step b. 

(2) Inspect fuel supply pump (3, Figure 3-16) lever face (9) for wear. Replace fuel supply pump if 

lever face is worn flat or concave. 

 

d. Test, bench.

 (1) Remove fuel supply pump, refer to step b. 

 (2) Perform vacuum/pressure test as follows: 

 (a) Install vacuum/pressure gage to fuel inlet (7, Figure 3-16). 

(b) Move primer lever (6) all the way downward. Release lever and at the same time observe 

gage. 

1 Gauge needle should read the same value each time primer lever is moved all 

the way downward and released. Gauge needle should then slowly return to "0" 

each time. Repeat several times. 

2 If gauge needle reads different values on different attempts, does not move at 

all, or rapidly returns to "0", fuel supply pump is defective and must be replaced. 

(c) Remove vacuum/pressure gage from fuel inlet (7) and install vacuum/pressure gage on 

fuel outlet (8). 

(d) Move primer lever (6) all the way upward. Release lever and at the same time observe 

gage. 

1 Gauge needle should initially read 4-6 psi (28-41 kPa), then quickly return to 

"0". This indicates that the outlet valve and diaphragm are in good condition, 

supply pump is operating properly and should be reinstalled on engine. 

2 If gauge needle does initially read same value as indicated above and then 

returns immediately back to "0", fuel supply pump is defective and must be 

replaced. 

 (e) Remove vacuum/pressure gauge from fuel outlet (8). 

 (3) Perform leakage test as follows: 

 (a) Install a plug on fuel outlet (8, Figure 3-16). 

(b) Install regulated pressure air line on fuel inlet (7, Figure 3-15) and apply 20 psi (140 kPa) 

pressure. 
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__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

(c) Submerge pump in clean diesel fuel and look for air bubbles. Replace fuel supply pump 

if air bubbles are present. 

 (d) Remove plug and regulated pressure air line. 

e. Replacement.

 (1) Remove fuel supply pump, refer to step b. 

(2) Inspect fuel supply pump, refer to step c. Replace fuel supply pump if lever face is worn flat or 

concave. 

 (3) Perform bench test, refer to step d. Replace if fuel supply pump fails bench test. 

 (4) For installation of fuel supply pump, refer to step f. 

f. Installation.

 (1) Remove all covering installed during step b (4). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Apply Thread Lock and Sealer (LOCTITE 242) to threads of capscrews (1, Figure 3-16). 

NOTE 

Pump lever must be positioned above fuel supply pump push rod before 

fuel supply pump can be installed. 

(4) Position o-ring (4) and fuel supply pump (3) on engine block. Install flat washers (2) and 

capscrews (1). Torque capscrews evenly to 22 lb-ft (30 Nm). 

CAUTION

Thread sealant can cause damage to fuel system. Do not allow sealant to 

get into fuel system. Failure to comply could result in damage to fuel 

system. 

 (5) Apply Thread Lock and Sealer (LOCTITE 242) to threads of fuel inlet (7) and fuel outlet (8). 
ARMY TM 9-2815-260-24 

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CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

(6) Install fuel line (6). Reconnect fuel supply line to fuel inlet (7, Figure 3-16). Torque fuel lines to 

22 lb-ft (30 Nm). 

 (7) Bleed fuel system, refer to paragraph 3.12.1. 

3.12.4. FUEL LINES.

a. Removal.

CAUTION

Fuel injection pump gets very hot during operation. Never steam clean or 

pour water on fuel injection pump while fuel injection pump is running or 

warm. Failure to comply could cause seizure of internal rotating parts. 

CAUTION

Dirt in the fuel system can damage components or cause poor engine 

performance. Always thoroughly clean the area around connection before 

disconnecting. Always cover all openings after disconnecting. Failure to 

comply can cause damage to components or poor engine performance. 

 (1) Thoroughly clean outside surfaces of fuel lines and surrounding area. 

 (2) Remove capscrews (6, Figure 3-17) and loop clamps (5). 

 (3) Remove capscrews (17) and loop clamps (18, 19 and 20). 

__________ 

WARNING

Diesel and JP fuels are flammable and toxic to eyes, skin, and respiratory 

tract. Skin and eye protection required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-48 

NOTES 

Catch fuel in suitable container. Dispose of fuel in accordance with local 

ordinances. 

Disconnect all fuel delivery (pressure) lines from injection pump using a 

suitable 17 mm deep-well crowsfoot socket. 

(4) Disconnect coupling nut (33, Figure 3-17), remove clamp (15) and remove supply line from fuel 

filter, refer to paragraph 3.12.2. 

 (5) Disconnect coupling nut (34) on return tube (3). 

(6) Disconnect coupling nuts (2) securing tubes (4) to injectors. Loosen coupling nut (35) connected 

to T-fitting (36). Remove tubes, coupling nuts and return fuel line. 

(7) Tag and disconnect fuel injection lines (7, 8, 9, 10, 11 and 12) from fuel injectors and fuel 

injection pump. 

 (8) Cover all openings to prevent entry of foreign material. 

b. Inspection.

 (1) Remove fuel lines, refer to step a. 

 (2) Inspect all fuel lines and seals for wear, kinks, or fitting damage. Replace as necessary. 

 (3) Ensure all connections are open. Replace as necessary. 

 (4) Inspect all removed o-rings, sealing washers, and fittings. If damaged, replace. 

c. Replacement.

 (1) Remove fuel lines, refer to step a. 

 (2) Inspect fuel lines and seals, refer to step b. Replace if worn, kinked, or fitting damage is present. 

 (3) Install fuel lines, refer to step d. 

d. Installation.

 (1) Remove all covering installed during step a (8). 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

(2) Connect fuel injection lines (7, 8, 9, 10, 11 and 12 , Figure 3-17) to fuel injectors and fuel 

injection pump as tagged during removal. Torque fuel injection lines to 20 lb-ft (27 Nm). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

3-49/3-50 BLANK 

 (3) Position coupling nuts (2) on tubes. 

(4) Position tubes (4) on T-fitting (36) and secure with coupling nuts (2). Retighten coupling nut (35). 

Torque coupling nuts to 20 lb-ft (27 Nm). 

 (5) Position coupling nut (34) on return tube and connect to fuel injection pump (26). 

 (6) Position coupling nut (33) on fuel supply line. 

 (7) Connect supply line to fuel filter and install clamp (15). 

(8) Position loop clamps (5, 18, 19 and 20,) on fuel injection lines (7, 8, 9, 10, 11 and 12) and secure 

the capscrews (6 and 7). 

 (9) Bleed fuel system, refer to paragraph 3.12.1. 

3.12.5 FUEL INJECTION PUMP.

a. Inspection.

Inspect fuel injection pump for cracks, leaks, or obvious signs of damage. Notify next higher maintenance 

level if cracked, leaking, or otherwise damaged. 

3.12.6. FUEL INJECTION NOZZLE ASSEMBLY.

a. Inspection.

Inspect fuel injection nozzle assembly for cracks, leaks, or obvious signs of damage. Notify next higher 

maintenance level if cracked, leaking, or otherwise damaged. 

ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-1 

CHAPTER 4 

DIRECT SUPPORT MAINTENANCE INSTRUCTIONS 

Section I. TROUBLESHOOTING 

4.1. DIRECT SUPPORT TROUBLESHOOTING PROCEDURES.

Purpose of Troubleshooting Flowchart.

This section contains troubleshooting information for locating and correcting operating troubles which may develop 

in the engine. Each malfunction for an individual component, unit, or system is followed by a list of tests or 

inspections which will help you to determine probable causes and corrective action to take. You should perform 

tests/inspections and corrective actions in order listed. 

Table 4-1 cannot list all malfunctions that can occur, nor all tests or inspections and corrective actions. If a 

malfunction is not listed or cannot be corrected by listed corrective actions, notify your supervisor. 

 NOTE 

Before you use Table 4-1, be sure you have performed your PMCS. Prior 

to performing troubleshooting procedures within this manual, perform 

troubleshooting procedures per TM 9-6115-672-14. 

SYMPTOM INDEX 

 

Malfunction Page 

 Engine Fails to Crank..........................................................................................................................4-2 

 Starter Operates But Engine Does Not Turn Over ..............................................................................4-3 

 Engine Cranks But Fails to Start .........................................................................................................4-4 

 Engine Misfires Or Runs Erratically Or Stalls Frequently ..................................................................4-5 

 Engine Does Not Develop Full Power ................................................................................................4-6 

 Engine Overheating.............................................................................................................................4-7 

 Excessive Oil Consumption.................................................................................................................4-7 

 Low Oil Pressure.................................................................................................................................4-8 

 Excessive Fuel Consumption...............................................................................................................4-9 

 Black or Gray Exhaust Smoke.............................................................................................................4-10 

 Blue or White Exhaust Smoke ............................................................................................................4-11 

 Engine Knocks ....................................................................................................................................4-12 

 Engine Makes Abnormal Noise...........................................................................................................4-13 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-2 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 1 of 12) 

 OK Not OK 

ENGINE FAILS TO CRANK

Remove starter (refer to 

paragraph 3.9.2), and test. 

(refer to paragraph 4.3.2).

Repair or replace faulty 

components (refer to 

paragraph 4.3.2).

Test starter motor armature 

and field windings (refer to 

paragraph 4.3.2).

Notify next higher level 

of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 

9-6115-672-14 or other applicable TM).

Engine fails to crank.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-3 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 2 of 12) 

 Not OK 

 OK Not OK 

STARTER OPERATES BUT ENGINE 

DOES NOT TURN OVER.

Manually turn flywheel 

using manual turning tool.

Remove starter (refer to paragraph 

3.9.2) and check for worn or broken 

starter pinion gear 

(refer to paragraph 4.3.2).

Replace flywheel ring gear 

(refer to paragraph 4.8.1).

Starter operates but engine 

does not turn over.

Notify next higher 

level of maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-4 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 3 of 12) 

 OK 

 OK Not OK 

ENGINE CRANKS BUT FAILS TO START

Engine cranks but fails to start.

Clean, repair, or replace fuel 

injection nozzle as necessary 

(refer to paragraph 4.6.2).

Perform end item troubleshooting 

procedures (refer to TM 

9-6115-672-14 or other applicable TM).

Test fuel injection nozzle for correct 

opening pressure and correct spray 

pattern. (refer to paragraph 4.6.2).

Test fuel injection pump 

timing 

(refer to paragraph 5.3.1).

Test for defective fuel 

injection pump (refer to 

paragraph 5.3.1).

Time fuel 

injection pump 

(refer to 

paragraph 5.3.1).

Replace fuel injection 

pump 

(refer to paragraph 5.3.1).

Notify next higher 

level of 

maintenance.

 Not OK 

 Not OK 

 OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-5 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 4 of 12) 

 Not OK 

 Not OK 

 Not OK 

 OK 

 OK 

 Not OK 

 OK 

 OK Not OK 

ENGINE MISFIRES OR RUNS ERRATICALLY OR 

STALLS FREQUENTLY

Engine misfires or runs erratically 

of stalls frequently.

Inspect for dirty, defective, or 

leaking fuel injection nozzles 

(refer to paragraph 3.12.6).

Test, repair, or replace fuel 

injection nozzles (refer to 

paragraph 4.6.2).

Test for defective fuel injection 

pump (refer to paragraph 5.3.1).

Test fuel injection 

pump timing (refer to 

paragraph 5.3.1).

Time fuel injection 

pump (refer to 

paragraph 5.3.1).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Repair or replace fuel 

injection pump (refer to 

paragraph 5.3.1).

Test for low engine 

compression (refer to 

paragraph 3.7.1).

 OK 

 Not OK 

Check valve adjustment 

(refer to paragraph 4.7.2).

Notify next higher 

level of maintenance.

Check for weak valve 

springs (refer to 

paragraph 4.7.3).

Adjust valves (refer to 

paragraph 4.7.2).

 OK 

Replace valve springs 

(refer to paragraph 4.7.4).

Check for stuck or burnt 

valves 

 (refer to paragraph 4.7.4).

Replace valves (refer 

to paragraph 4.7.4).

 Not OK 

 OK 

Notify next higher 

level of maintenance.
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-6 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 5 of 12) 

 Not OK 

 Not OK 

 Not OK 

 OK 

 Not OK 

 OK Not OK 

 Not OK 

 OK Not OK 

 Not OK OK 

ENGINE DOES NOT DEVELOP FULL POWER

Engine does not 

develop full power.

Inspect for dirty, defective, 

or leaking fuel injection 

nozzles 

(refer to paragraph 3.12.6).

Test, repair, or replace fuel 

injection nozzles (refer to 

paragraph 4.6.2).

Test fuel injection 

pump timing (refer to 

paragraph 5.3.1).

Time fuel injection 

pump (refer to 

paragraph 5.3.1).

Check valve 

adjustment (refer to 

paragraph 4.7.2).

Adjust valves 

(refer to 

paragraph 4.7.2).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Test for low engine 

compression (refer to 

paragraph 3.7.1).

Did oil pressure 

increase?

Check for defective 

turbocharger (refer to 

paragraph 4.4.1).

Replace turbocharger 

(refer to paragraph 

4.4.1).

 OK 

Replace engine. Remove cylinder head and inspect 

for defective cylinder head gasket 

(refer to paragraph 4.7.4).

 OK 

Replace cylinder head 

gasket (refer to paragraph 

4.7.4).

Check for weak valve 

springs (refer to paragraph 

4.7.3).

 OK 

Replace valve 

springs (refer to 

paragraph 4.7.4).

Check for stuck or 

burnt valves (refer 

to paragraph 4.7.4).

Notify next higher 

level of maintenance.

Replace valves (refer to 

paragraph 4.7.4).

 OK 

 OK Not OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-7 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 6 of 12) 

 Not OK OK 

ENGINE OVERHEATING

Engine overheating. 

Test fuel injection pump 

Timing (refer to paragraph 

5.3.1). 

Time fuel injection 

pump (refer to 

paragraph 5.3.1). 

Perform end item troubleshooting 

procedures (refer to TM 9-6115-

672-14 or other applicable TM). 

Notify next higher 

Level of 

maintenance. 

 OK Not OK 

EXCESSIVE OIL CONSUMPTION 

Excessive oil consumption. 

Perform end item troubleshooting procedures 

(refer to TM 9-6115-672-14 or other applicable 

TM). 

Check for defective intake or exhaust valve 

seals or valve guides (refer to paragraph 4.7.4). 

Repair or replace defective components (refer 

to paragraph 4.7.4). 

Notify next higher level of 

maintenance. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-8 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 7 of 12) 

 OK Not OK 

 Not OK OK 

LOW OIL PRESSURE

Low oil pressure.

Check for defective 

regulating valve (refer 

to paragraph 4.5.2).

Replace regulating 

valve (refer to 

paragraph 4.5.2).

Check for defective oil 

pump (refer to paragraph 

5.4.9).

Check for clogged oil 

pickup tube assembly 

(refer to paragraph 

4.5.4).

Remove and clean 

pickup tube assembly 

(refer to paragraph 4.5.4).

Replce defective oil 

pump (refer to 

paragraph 5.4.9).

Check for worn 

rocker arm bushings 

(refer to paragraph 

4.7.3).

 Not OK OK 

Replace rocker arm 

bushings (refer to 

paragraph 4.7.3).

Notify next higher 

level of 

maintenance.

 OK Not OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-9 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 8 of 12) 

 Not OK

 OK 

 OK Not OK 

EXCESSIVE FUEL CONSUMPTION

Replace turbocharger 

(refer to paragraph 

4.4.1).

Replace 

engine.

OK

 Not OK 

 OK Not OK 

 OK Not OK 

 Not OK OK 

 OK Not OK 

 OK Not OK 

Excessive fuel consumption.

Check for dirty, defective, or 

leaking fuel injection nozzles 

(refer to paragraph 3.12.6).

Clean, repair, or 

replace fuel injection 

nozzles (refer to 

paragraph 4.6.2).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 

or other applicable TM).

Test fuel injection 

pump timing (refer 

to paragraph 5.3.1).

Time fuel injection 

pump (refer to 

paragraph 5.3.1).

Check for defective 

fuel injection pump 

(refer to paragraph 

5.3.1).

Replace fuel injection 

pump (refer to 

paragraph 5.3.1).

Check for defective 

turbocharger (refer to 

paragraph 4.4.1).

Check for improperly 

adjusted valves (refer 

to paragraph 4.7.2).

Adjust valves (refer 

to paragraph 4.7.2).

Check for low engine 

compression (refer to 

paragraph 3.7.1).

Notify next higher 

level of maintenance.

Did oil pressure 

increase?

Check for worn or 

stuck valves (refer to 

paragraph 4.7.4).

Notify next higher 

level of maintenance.

Repair/Replace valve 

seats/valves (refer to 

paragraph 4.7.4).
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-10 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 9 of 12) 

 Not OK 

 Not OK OK 

 OK Not OK 

 Not OK OK 

BLACK OR GRAY EXHAUST SMOKE

Black or gray 

exhaust smoke.

Check for dirty, defective, or 

leaking fuel injection nozzles 

(refer to paragraph 3.12.6).

Clean, repair, or replace 

fuel injection nozzles (refer 

to paragraph 4.6.2).

Test fuel injection 

pump timing (refer to 

paragraph 5.3.1).

Time fuel injection 

pump (refer to 

paragraph 5.3.1).

Check for defective 

turbocharger (refer to 

paragraph 4.4.1).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Check for defective fuel 

injection pump (refer to 

paragraph 5.3.1).

Replace fuel injection 

pump (refer to paragraph 

5.3.1).

Replace turbocharger 

(refer to paragraph 

4.4.1).

Notify next higher 

level of maintenance.

 OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-11 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 10 of 12) 

 Not OK OK 

BLUE OR WHITE EXHAUST SMOKE

Blue or white 

exhaust smoke.

Check for defective intake or 

exhaust valve seats or valve guides 

(refer to paragraph 4.7.2).

Repair or replace defective 

components (refer to 

paragraph 4.7.3).

Notify next higher 

level of maintenance.

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Check fuel injection pump 

timing (refer to paragraph 

5.3.1).

 OK Adjust fuel injection 

pump timing (refer to 

paragraph 5.3.1).

 Not OK 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-12 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 11 of 12) 

OK

Not OK OK

OK

Not OK

ENGINE KNOCKS

Engine knocks.

Check fuel injection pump 

timing 

 (refer to paragraph 5.3.1).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Check for dirty, defective, or 

leaking fuel injection nozzles 

(refer to paragraph 3.12.6).

OK Not OK

Adjust fuel injection 

pump timing (refer to 

paragraph 5.3.1).

Clean or replace fuel injection 

nozzles (refer to paragraph 

4.6.2).

Test for low engine 

compression (refer to 

paragraph 3.7.1).

Check for worn or 

stuck valves (refer to 

paragraph 4.7.4).

Notify next higher 

level of maintenance.

Repair/Replace valve 

seats/valves (refer to 

paragraph 4.7.4).

Notify next higher 

level of maintenance.

Not OK

Did Oil Pressure 

Increase?

Replace 

Engine.

Yes

No
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-13 

TABLE 4-1. DIRECT SUPPORT TROUBLESHOOTING 

(Sheet 12 of 12) 

 Not OK OK 

 OK Not OK 

 Not OK OK 

Abnormal engine noise.

Check for improperly adjusted 

valves (refer to paragraph 

4.7.2).

Adjust valve 

clearance (refer to 

paragraph 4.7.2).

Check for damaged rocker 

arms (refer to paragraph 

4.7.3).

Replace damaged 

rocker arms (refer to 

paragraph 4.7.3).

Perform end item troubleshooting 

procedures (refer to TM 9-6115-672-14 or 

other applicable TM).

Check for loose flywheel 

(refer to paragraph 4.8.1).

ABNORMAL ENGINE NOISE

Notify next higher level 

of maintenance.

Tighten bolts to specified torque 

(refer to paragraph 4.8.1).
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-14 

Section II. MAINTENANCE PROCEDURES 

4.2. GENERAL.

This section contains direct support maintenance procedures. Deficiencies noted during inspection which are beyond 

the scope of direct support level maintenance shall be reported to the next higher level of maintenance. 

4.3. ELECTRICAL SYSTEM MAINTENANCE.

4.3.1. BATTERY CHARGING ALTERNATOR.

a. Test.

(1) Remove battery charging alternator, refer to paragraph 3.9.1. 

(2) Mount battery charging alternator on test fixture capable of providing 5000 alternator rpm. 

 CAUTION

Make sure connections are tight to avoid possible damage to instruments, 

battery charging alternator, or wiring due to short circuits. 

 (3) Set up circuit as shown in Figure 4-1. 

 NOTE 

Carbon pile and ammeter must be capable of handling the alternator rated 

output. 

(4) Starting with the carbon pile off, slowly increase load while observing ammeter and maintaining 

5000 rpm. Increase load until an output voltage of 27.0 to 29.0 VDC is achieved. Record the 

output current at this point. Acceptable current is 38 amperes at 70 to 80°F (21.1 to 26.7°C). 

FIGURE 4-1. BATTERY CHARGING ALTERNATOR TEST CIRCUIT 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-15 

b. Repair. 

 NOTE 

The following procedure is provided for repairing the battery charging 

alternator. Remove battery charging alternator (refer to paragraph 3.9.1.) 

and place on a suitable workbench. 

(1) Remove terminal parts set (12, Figure 4-2) from slip ring end housing and through bolts (10) from 

drive end housing (1). 

 (2) Remove two attaching bolts (16) from regulator assembly (8). 

 (3) Remove attaching bolt from suppression capacitor (11). 

 NOTE 

When removing regulator assembly (8), exercise caution not to damage 

service brush set (13) 

(4) Remove regulator assembly (8) and suppression capacitor (11) from slipring end housing (5). 

 CAUTION

Do not insert screwdriver blades deeper than 1/16 inch (1.587 mm) to avoid 

damaging stator winding. 

(5) Match mark front and rear housing. Pry unit apart by inserting two flat tip screwdrivers in 

opposite openings between stator (9) and slip ring end housing (5), refer to Figure 4-3. 

(6) Remove slip ring end housing (5) and stator (9) from drive end housing (1). 

 (7) Tag and remove stator (9) leads from rectifier (6). 

 (8) Remove bolts (16) and rectifier (6) from slip ring end housing (5). 

(9) If not previously done, remove pulley and fan from rotor assembly (3, Figure 4-2) shaft. 

(10) Remove splash shield (7) from service slip ring end of rotor assembly (3). 

(11) Using arbor press, remove rotor assembly (3) from drive end housing (1). 

(12) Remove bearing retaining screws and press bearing (2) from drive end housing (1). 

(13) Remove bearing (4) from rotor assembly (3). 

(14) Check or replace brush assembly as follows: 

(a) Refer to Figure 4-4 and check measurement “A”. If dimension “A” is less than 0.2 in. 

(5mm), replace the brush assembly. When the new brush assembly is installed the new 

dimension “A” should not exceed 0.4 in. (10mm). 

(b) Always replace the bearing (4) when replacing the brush assembly. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-16 

FIGURE 4-2. BATTERY CHARGING ALTERNATOR ASSEMBLY 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-17 

FIGURE 4-3. STATOR AND REAR HOUSING SEPARATION. 

FIGURE 4-4. TESTING BRUSH ASSEMBLY 

 (14) Check or replace exciting diodes as follows: 

(a) Set multimeter for ohms and check exciting diodes (refer to Figure 4-5) by noting 

multimeter indications between each of the diode leads (A) and the D+ stud (B). Reverse 

multimeter leads, repeat checks and note indications. 

(b) If readings are the same in both directions for any diode, replace exciting diodes 

assembly. A good diode will show a high indication in one direction and a low indication 

in the other. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-18 

FIGURE 4-5. TESTING EXCITING DIODES 

FIGURE 4-6. TESTING POSITIVE/NEGATIVE DIODES 

(15) Check or replace positive diodes as follows: 

(a) Set multimeter for ohms and connect positive test probe of ohmmeter to positive heat sink 

(A) and negative test probe to leads (B) of diodes (refer to Figure 4-6). Meter must show 

continuity. Reverse leads, repeat check and note indications. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-19 

(b) Replace entire rectifier bridge assembly if readings are the same in both directions for any 

diode. A good diode will have a high indication in one direction and a low indication in the 

other. 

(16) Check or replace negative diodes as follows: 

(a) Set multimeter for ohms and connect positive test probe of ohmmeter to positive heat sink (C) 

and negative test probe to leads (B) of diodes (refer to Figure 4-6). Meter must show 

continuity. Reverse leads, repeat check and note indications. 

(b) Replace entire rectifier bridge assembly if readings are the same in both directions for any 

diode. A good diode will have a high indication in one direction and a low indication in the 

other. 

FIGURE 4-7. TESTING STATOR WINDINGS 

(17) Check or replace stator as follows: 

(a) Set multimeter for ohms and check stator (refer to Figure 4-7) for open circuits between 

point D (lamination) and each terminal A, B, and C. 

(b) If continuity is noted between lamination and any terminal, stator is defective and must be 

replaced. 

(c) Set multimeter for ohms and check stator windings (refer to Figure 4-7) for continuity 

between terminals A-B, A-C, and B-C. 

 (d) If open, replace stator. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-20 

(18) Check/replace rotor assembly. 

(a) Set multimeter for ohms, clean sliprings with solvent, and check rotor assembly (refer to 

Figure 4-8) for 9.0 to 14.0 ohms indication between slip rings. 

 (b) Check that open circuits are indicated between pole fingers and each slip ring. 

(c) Replace entire rotor assembly if indications are other than stated in (a) and (b) above. 

FIGURE 4-8. TESTING ROTOR 

c. Assembly.

(1) Install bearing (4, Figure 4-2) on rotor assembly (3). 

 (2) Install bearing plate, bearing (2) and drive end housing (1) on rotor assembly (3). 

 (3) Install bearing plate bolts (16), through front of drive end housing (1); alternately tighten bolts 

which pull bearing (2) into drive end housing (1). 

 (4) Install splash shield (7) on to service slip ring end of rotor assembly (3). 

 (5) Connect tagged stator (9) leads to rectifier (6). 

 (6) Install bolts (16) and rectifier (6) on slip ring end housing (5). 

 (7) Align drive end housing (1) with slip ring end housing (5) and tap into position using soft face 

mallet. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-21 

NOTE 

When installing regulator assembly (8) exercise caution not to damage 

service brush set (13). 

 (8) Install regulator assembly (8) and suppression capacitor (11) on slip ring end housing (5). Connect 

lead to positive terminal. 

 (9) Install terminal part set (12) to slipring end housing (5) and through bolts (10) to drive end housing 

(1). 

 (10) Install pulley and fan to rotor assembly (3) shaft. 

4.3.2. STARTER.

a. Test.

 (1) Remove starter, refer to paragraph 3.9.2. 

 (2) Turn overrunning clutch drive (17, Figure 4-10) clockwise by hand. Pinion should turn freely. 

 (3) Turn pinion counterclockwise. A definite resistance should be felt. If clutch assembly is 

defective, disassemble the starter clutch. 

 (4) If armature turns freely and the clutch is not defective, test the starter under no-load conditions. 

CAUTION

Never operate starter longer than 30 seconds. Allow at least two minutes 

for cooling and battery recovery before operating again. Overheating, 

caused by excessive operation, will seriously damage starter. 

(5) Connect a 24 VDC source (A) to starter battery terminal (B) and starter frame (C) as shown. Use 

heavy duty cables, refer to Figure 4-9. 

 (6) Connect a remote start switch (D) between switch terminal (E) and battery terminal (B). 

 (7) When switch is activated, starter should engage and run. 
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(8) If solenoid only chatters, hold-in winding is open-circuited. If nothing happens, either pull-in 

winding is open-circuited or mechanical parts are sticking. To check for sticking, remove starter 

motor, then solenoid end cover and push plunger by hand. 

FIGURE 4-9. STARTER BENCH TEST SETUP 

NOTE 

The solenoid cannot be repaired.

(9) If solenoid engages properly, but starter does not run, check main contact points, bearings, 

brushes, reduction gears, armature and field windings. Refer to Step (13). 
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FIGURE 4-10. STARTER ASSEMBLY 
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b. Repair. 

NOTE 

The following procedure is provided for repairing the starter. Remove 

starter (refer to paragraph 3.9.2.) and place on a suitable workbench. 

 (1) Remove nut (5, Figure 4-10) and washer (28). 

(2) Disconnect yoke assembly lead wire (6) at magnetic switch assembly (24). Refer to Figure 4-11 

for detailed view. 

FIGURE 4-11. DISCONNECTING LEAD WIRE (TYPICAL) 

(3) Remove two through bolts (7, Figure 4-10). Refer to Figure 4-12 for detailed view. 

FIGURE 4-12. REMOVING THROUGH BOLTS (TYPICAL) 
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(4) Remove two screws (11, Figure 4-10) and starter end frame (12). Remove yoke assembly (39). 

Refer to Figure 4-13 for detailed view. 

FIGURE 4-13. REMOVING STARTER END FRAME AND YOKE ASSEMBLY (TYPICAL) 

(5) Lift brush springs and remove brushes from brush holder (13). Remove brush holder assembly 

(13), refer to Figure 4-10. Refer to Figure 4-14 for detailed view. 

FIGURE 4-14. REMOVING BRUSHES 
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(6) Remove armature (14, Figure 4-10) from magnetic switch assembly (24). Refer to Figure 4-15 for 

detailed view. 

FIGURE 4-15. REMOVING ARMATURE 

(7) Remove three screws (15, Figure 4-10) from housing (16). Remove housing (16) from magnetic 

switch assembly (24). Refer to Figure 4-16 for detailed view. 

FIGURE 4-16. REMOVING HOUSING (TYPICAL) 
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(8) Remove overrunning clutch (17, Figure 4-10) from magnetic switch assembly (24). Refer to Figure 4-17 

for detailed view. 

FIGURE 4-17. REMOVING OVERRUNNING CLUTCH (TYPICAL) 

(9) Remove steel ball (18, Figure 4-10) from overrunning clutch (17). Refer to Figure 4-18 for detailed view. 

FIGURE 4-18. REMOVING STEEL BALL 
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(10) Remove starter pinion (19, Figure 4-10), retainer (20), and five rollers (21) from housing (16). 

Refer to Figure 4-19 for detailed view. 

FIGURE 4-19. REMOVING PINION, RETAINER, AND ROLLERS (TYPICAL) 

(11) Remove spring (23, Figure 4-10) from magnetic switch assembly (24). Refer to Figure 4-20 for 

detailed view. 

FIGURE 4-20. REMOVING WASHER AND SPRING 

(12) If necessary, remove screw (25, Figure 4-10), nuts (26 and 27), washers (28 through 30), and 

lockwashers (31 and 32) from terminal studs on magnetic switch assembly (24). 
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(13) Check and replace starter components. 

 (a) Check armature commutator run-out as follows (Refer to Figure 4-21): 

FIGURE 4-21. CHECKING COMMUTATOR RUN-OUT 

 (1) Place armature bearings on V-blocks. 

 (2) Zero dial indicator on commutator. 

(3) Rotate armature and record run-out. Standard is 0.0008 inch (0.02 mm), with a 

limit of 0.00197 inch (0.5 mm). 

(b) Using a micrometer, measure OD of commutator. If measurement is less than 1.38 inches 

(35 mm), replace armature. Refer to Figure 4-22. 

FIGURE 4-22. MEASURING COMMUTATOR OD 
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 (c) Measure commutator segment mica depth as shown in Figure 4-23. If depth is less than 

0.0079 inch (0.2 mm), undercut the mica. 

FIGURE 4-23. MEASURING SEGMENT MICA DEPTH 

(d) Check commutator surface for burn spots. This usually indicates an open circuit. Remove 

these spots using #400 abrasive paper (Refer to Appendix E). 

(e) Inspect bearings (34 and 35, Figure 4-10) for wear and damage. If damaged or worn, 

replace bearings using a press. Refer to Figure 4-24 for detailed view. 

FIGURE 4-24. INSPECTING AND REPLACING BEARINGS 
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(f) Check field windings of yoke for wear or damage. Check all connections for clean and 

tight solder joints. 

(g) Measure brush length, refer to Figure 4-25. If less than 0.51 inch (13 mm), replace brush 

holder and/or yoke assembly. 

FIGURE 4-25. MEASURING BRUSH LENGTH 

(h) Check brush springs for damage or corrosion. If damaged or corroded, replace brush 

holder. 

(i) Check that all overrunning clutch rotates freely in direction of starter rotation and that it 

will be locked when trying to rotate in opposite direction. Refer to Figure 4-26 for 

detailed view. 

FIGURE 4-26. CHECKING OVERRUNNING CLUTCH 
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(j) Using a growler tester, place armature on it and hold a hacksaw blade against armature 

core while slowly rotating armature, refer to Figure 4-27. A short circuited armature 

causes blade to vibrate and be attracted to core. An armature which is short circuited 

must be replaced. 

FIGURE 4-27. GROWLER TEST 

(k) Set multimeter for ohms and touch one probe to a commutator segment and other one to 

armature core, refer to Figure 4-28. There should be no continuity, armature is grounded. 

 Replace armature if grounded. 

FIGURE 4-28. TESTING FOR GROUNDED WINDINGS 
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(l) Set multimeter for ohms and touch probes to two segments, refer to Figure 4-29. There 

should be continuity at any point. If there is no continuity, winding is open circuited. 

Replace the armature if open circuited. 

FIGURE 4-29. CHECKING FOR OPEN CIRCUIT WINDINGS 

(m) Set multimeter for ohms and touch one probe to positive brush holder and other one to the 

holder plate, refer to Figure 4-30. There should be no continuity. If there is continuity, 

replace brush holder. 

FIGURE 4-30. CHECKING BRUSH HOLDER ASSEMBLY 
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(n) Using a multimeter, touch one probe to field winding end of brush and other one to bare 

surface of yoke body, refer to Figure 4-31. There should be no continuity. If there is 

continuity, field windings are grounded. Replace the yoke assembly. 

FIGURE 4-31. CHECKING FIELD COILS 

(o) Using a multimeter, touch one probe to lead wire and other one to brush, refer to Figure 

4-32. There should be continuity. If there is no continuity, field windings are open 

circuited. Replace the yoke assembly. 

FIGURE 4-32. CHECKING FOR OPEN FIELD COIL 
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c. Assembly. 

(1) If removed, install nuts (26 and 27, Figure 4-10), washers (28 through 30), lockwashers (31 and 

32), and screw (25). 

(2) Apply general purpose grease (630AA) to retainer (20), rollers (21), overrunning clutch (17), steel 

ball (18), spring (23), and bearings (34 and 35). 

(3) Install spring (23, Figure 4-10) in magnetic switch assembly (24). 

(4) Install five rollers (21), retainer (20), and starter pinion (19) in housing (16). 

(5) Place steel ball (18) in overrunning clutch (17) and install both in housing (16). 

(6) Position assembled housing (16) on magnetic switch assembly (24) and secure with three screws 

(15). Tighten screws 5.1 to 8.7 lb-ft (6.9 to 11.8 Nm). 

(7) Install armature (14) in yoke (39). 

(8) Position brush holder (13) over armature (14) commutator. Lift springs and install brushes, refer 

to Figure 4-33. Ensure negative brushes (connected to brush holder) are installed in negative holes 

(not insulated) and positive brushes (connected to yoke) are installed in positive holes (separated 

from plate with insulator). Ensure positive brush leads are not grounded. 

FIGURE 4-33. INSTALLING BRUSHES 

BRUSH SPRING

POSITIVE BRUSH

INSULATOR

NEGATIVE BRUSH

NEGATIVE BRUSH HOLDER HOLE

POSITIVE BRUSH HOLDER HOLE
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(9) Position end frame cover (12, Figure 4-10) on yoke (39) engaging tab on cover with lead wire 

grommet, refer to Figure 4-34. Secure with two screws (11). Tighten screws 1.95 to 3.40 lb-ft 

(2.6 to 4.6 Nm). 

FIGURE 4-34. INSTALLING COVER ON YOKE 

(10) Position yoke assembly (39, Figure 4-10) on magnetic switch assembly (24) engaging tab on yoke 

assembly with notch in magnetic switch, refer to Figure 4-35. Secure with two through bolts (7, 

Figure 4-10). Tighten through bolts 5.1 to 8.7 lb-ft (6.9 to 11.8 Nm). 

FIGURE 4-35. INSTALLING YOKE 
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(11) Connect yoke assembly lead wire (6) to terminal on magnetic switch assembly with washer(s) and 

nut (4). Tighten nut to 18.1 to 26.0 lb-ft (24.5 to 35.3 Nm). Ensure rubber boot (36) is installed 

securely. 

4.4. INTAKE AND EXHAUST SYSTEM MAINTENANCE.

4.4.1. TURBOCHARGER.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 __________ 

 WARNING

Exhaust system is very hot after operating engine. After operating engine, 

allow exhaust system to cool before removal. Failure to comply could result 

in personal injury. 

CAUTION

When cleaning turbocharger, do not spray directly into compressor cover 

or turbine housing. Failure to comply could result in damage to the 

turbocharger. 

NOTE 

If turbocharger inspection is required, do not clean exterior prior to 

removal. Cleaning exterior may wash away evidence of a potential failure 

mode. 

(1) Thoroughly clean exterior of turbocharger and surrounding area to prevent entry of dirt into air 

intake system during removal. 

(2) Remove air intake line and exhaust line from turbocharger (12, Figure 4-36), refer to TM 9-6115-

672-14. 

(3) Loosen clamps securing air intake manifold hose to turbocharger, refer to paragraph 4.4.2. 

CAUTION

Oil inlet line is fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (4) Disconnect oil inlet line (3, Figure 4-36) from fitting (6) on top of turbocharger (12). 
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(5) Remove capscrews (4) and disconnect oil return pipe (5). Remove line (5) and gasket (9); discard 

gasket (9). 

(6) Remove four mounting capscrews (10), nuts (11) securing turbocharger (12) to exhaust manifold. 

Remove turbocharger (12) and stainless steel gasket (13); discard gasket (13). 

 (7) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 The following inspection procedure is recommended for systematic failure analysis of a suspected 

turbocharger failure. This procedure will help to identify when a turbocharger has failed, and why it has 

failed so the primary cause of failure can be corrected. Proper diagnosis of a “non-failed” turbocharger is 

important for two reasons. First, identification of a “non-failed” turbocharger will lead to further 

investigation and repair of the cause of a performance complaint. Second, proper diagnosis eliminates 

unnecessary expense incurred when a “non-failed” turbocharger is replaced. 

 (1) Remove turbocharger, refer to step a. 

 (2) Inspect compressor housing inlet and compressor wheel. 

(a) Check compressor inlet and compressor wheel for foreign object damage. If foreign 

object damage is found, locate and correct source of foreign object damage. 

NOTE 

Score marks can be difficult to see. Provide adequate lighting to insure that 

damage is not overlooked. 

(b) Check compressor inlet for wheel rub on the housing. Check for score marks on housing 

and check tips of compressor wheel blades for damage. 

 (3) Inspect housing outlet. The outlet should be clean and free of dirt and oil. 

 (4) Inspect turbine housing inlet. 

(a) Check turbine housing inlet ports for oil in housing and excessive carbon deposit. Oil or 

excessive carbon deposits in the inlet port indicates an engine problem is likely. 

(b) Check turbine housing inlet ports for erosion of center walls. Center wall erosion 

(cracking or missing pieces) indicates excessive exhaust temperature. 
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FIGURE 4-36. TURBOCHARGER 
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 (5) Inspect turbine housing outlet and turbine wheel. 

NOTE 

Foreign object damage can be difficult to see. Provide adequate lighting to 

insure that damage is not overlooked. 

(a) Check blades inside turbine housing outlet Figure 4-37 for foreign object damage. 

Foreign object damage indicates an engine problem is likely. 

FIGURE 4-37. TURBOCHARGER INSPECTION POINTS 

(b) Inspect wheel blades and housing for evidence of wheel rub. Wheel rub can bend the tips 

of wheel blades and cause wear or damage to the housing. 

NOTE 

Note location and source of any oil leaks found.

(6) Inspect outside of center housing, connections to the compressor, and turbine housing for oil. 

 (7) Inspect internal center housing. 

NOTE 

Foreign object damage can be difficult to see. Provide adequate lighting to 

insure that damage is not overlooked. 

(a) Look through oil return hole Figure 4-38 to check condition of shaft and bearings. There 

should not be excess carbon deposits on shaft or in housing. 
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(b) Check for excessive “blueing” or “coking” of oil along the complete length of shaft. 

Excessive “blueing” or “coking” along the complete length of shaft indicates either a 

possible lack of lubrication caused by engine failure or improper operation, such as hot 

shutdowns. 

 (8) Perform turbocharger bench inspection. 

 (a) Mount turbocharger in vise. 

(b) Check shaft rotation and clearance by rotating shaft with both hands. Shaft should turn 

freely, however, there may be a slight amount of drag. 

NOTE 

There will be some “play” because the bearings inside center housing are 

free floating. 

(c) Pull up on compressor end of shaft and press down on turbine end while rotating shaft. 

The compressor wheel and turbine should not contact the housing at any point. 

(d) Check shaft end play by moving shaft back and forth while rotating. There will be some 

end play, but the wheels should not contact the housings. 

c. Replacement. 

 (1) Remove turbocharger, refer to step a. 

(2) Perform inspection procedures, refer to step b. If turbocharger fails any inspection portion, the 

unit is defective and must be replaced. If turbocharger passes inspection, continue with step c (3) 

listed below. 

(3) Test turbocharger per step d. Replace turbocharger if unit fails any portion of the tests. If 

turbocharger passes tests, install per step e. 

d. Test. 

 (1) Inspect turbocharger, refer to step b. 

 (2) Prelube turbocharger center housing bearings, refer to step e.(3). 

 (3) Perform radial bearing clearance test as follows: 

 (a) Fasten a plunger-type dial indicator to turbocharger mounting base. Assemble an 

extension adapter and 2.0 in. (51 mm) indicator extension rod onto dial indicator. 

(b) Grasp rotating shaft at both ends and move shaft toward indicator then away from 

indicator. Use care to move shaft in same direction as dial indicator tip travels and apply 

equal pressure at both ends of shaft. Refer to Figure 4-38. 
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(c) Observe and record total indicator reading. Bearing clearance should be 0.003 - 0.007 in. 

(0.08 - 0.18 mm). Replace turbocharger, refer to step d, if bearing clearance is out of 

specifications. 

 (4) Perform axial bearing end play test as follows: 

 (a) Mount base dial indicator so that indicator tip rests on end of shaft. Preload indicator tip 

and zero dial on indicator. Refer to Figure 4-38. 

 (b) Move shaft back and forth by hand. Refer to Figure 4-38. 

(c) Observe and record total indicator reading. Bearing end play should be 0.001 - 0.004 in. 

(0.025 - 0.102 mm). Replace turbocharger, refer to step d, if bearing end play is out of 

specifications. 

 (5) Install turbocharger, refer to step e. 

e. Install. 

CAUTION

If turbocharger failed because of foreign material entering the air intake 

system, be sure to examine the system and clean as required to prevent a 

repeat failure. 

CAUTION

Do not spin the rotor assembly with compressed air. Damage to the 

bearings can occur when using compressed air. 

 (1) Remove all covering installed during step a (7). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Prelube turbocharger: Fill center housing of turbocharger (12, Figure 4-36) with new engine 

lubricating oil through oil drain hole. Turn rotating assembly of turbocharger by hand to lubricate 

bearings. 

 (4) Position gasket (13) and turbocharger (12) on exhaust manifold. Install capscrews (10) and nuts 

(11) and tighten to 52 lb-ft (70 Nm). 

 (5) Position gasket (9) and oil return pipe (5) on turbocharger (12). Install capscrews (4 and torque to 

26 lb-ft (35 Nm). 
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FIGURE 4-38. INSPECTING TURBOCHARGER BEARINGS 

CAUTION

Oil inlet line is fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (6) Connect oil inlet line (3) to turbocharger (12) and torque to 20 lb-ft (27 Nm). 

 (7) Position hose (2) and hose clamps (1) on turbocharger (12) and intake manifold. Tighten hose 

clamps. 

 (8) Connect air intake line and exhaust line to turbocharger, refer to TM 9-6115-672-14. 

 (9) Place throttle system so engine cannot start, refer to TM 9-6115-672-14. 
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CAUTION

Excessive cranking on the engine using the starter can damage the starter. 

Do not crank engine longer than 30 seconds at a time, with a two minute 

break in between cranking attempts. Failure to comply could damage the 

starter. 

(10) Crank engine (without starting) using starter until oil pressure is within normal range. 

4.4.2. INTAKE MANIFOLD.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 (1) Thoroughly clean outside surface of intake manifold and surrounding area. 

 (2) Remove crankcase breather assembly. Refer to TM 9-6115-672-14. 

(3) Loosen hose clamps (1, Figure 3-7) and slide hose (2) down intake manifold (4), clear of 

turbocharger. 

 (4) Remove capscrews (3), intake manifold (4), and gasket (5). Discard gasket. 

 (5) Remove hose (2) and hose clamps (1) 

 (6) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Remove intake manifold, refer to step a. 

 (2) Inspect intake manifold (4, Figure 3-7) for cracks or damage. Inspect machined mounting surface 

for burrs or other defects which might prevent gasket (5) from sealing properly. Replace as 

needed. 

c. Replacement. 

 (1) Remove intake manifold, refer to step a. 

 (2) Inspect intake manifold, refer to step b. Replace intake manifold if damaged. 

 (3) For installation of intake manifold, refer to step d. 
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d. Installation. 

 (1) Remove all covering installed during step a (5). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Position hose clamps (1, Figure 3-7) and hose (2) on intake manifold (4). 

 (4) Position new gasket (5) and intake manifold (4) on cylinder head. Install capscrews (3) and torque 

to 52 lb-ft (70 Nm). 

(5) Position hose (2) and hose clamps (1) on turbocharger and intake manifold (4). Tighten hose 

clamps. 

 (6) Install crankcase breather assembly. Refer to TM 9-6115-672-14. 

4.4.3. EXHAUST MANIFOLD.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 (1) Remove turbocharger, refer to paragraph 4.4.1. 

NOTE 

Use guide studs to ease removal.

 (2) Remove capscrews (1, Figure 3-8), exhaust manifold (2), and gaskets (3). Discard gaskets. 

 (3) Remove all residue and gasket material from gasket surfaces. 

 (4) Thoroughly clean passages in exhaust manifold (2). 

 (5) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Remove exhaust manifold, refer to step a. 

 (2) Inspect exhaust manifold for cracks or damage. Inspect machined mounting surfaces for burrs or 

other defects which might prevent gaskets from sealing properly. Replace as needed. 
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c. Replacement. 

 (1) Remove exhaust manifold, refer to step a. 

 (2) Inspect exhaust manifold, refer to step b. Replace exhaust manifold if damaged. 

 (3) For installation of exhaust manifold, refer to step d. 

d. Installation. 

 (1) Remove all covering installed during step a (5). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Position gaskets (3, Figure 3-8) on exhaust manifold (2). 

 (4) Using guide studs, position exhaust manifold (2) on cylinder head. 

 (5) Apply antiseize compound (Refer to Appendix E) to capscrews (1). 

NOTE 

Tighten capscrews on No. 3 and No. 4 cylinders first.

 (6) Install capscrews (1) and torque evenly to 52 lb-ft (70 Nm). 

 (7) Install turbocharger, refer to paragraph 4.4.1. 

4.5. LUBRICATION SYSTEM MAINTENANCE

4.5.1. GENERAL.

This section provides maintenance for lubrication system components. 

4.5.2. OIL PRESSURE REGULATING VALVE ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 (1) Remove fan belt, refer to TM 9-6115-672-14. 

 (2) Remove plug (1, Figure 4-39) and washer (2) from timing gear cover. 

 (3) Remove spring (3) and oil pressure regulating valve (4). 
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 (4) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Remove oil pressure regulating valve assembly, refer to step a. 

 (2) Inspect cone of oil pressure regulating valve (4, Figure 4-39) for excessive wear or damaged 

sealing face. If oil pressure regulating valve shows excessive wear or damaged sealing face, 

replace both valve (4) and valve seat (5). Refer to next higher level of maintenance. 

FIGURE 4-39. OIL PRESSURE REGULATING VALVE ASSEMBLY 

 (3) Inspect spring (3) using the following steps. Replace per step c., if defective. 

 (a) Measure free length of spring (3). Free length of spring should be 4.55 in. (115.5 mm). 

(b) Using a spring tester (DO1168AA or equivalent), apply force to spring (3) until spring is 

compressed to a length of 1.68 in. (42.5 mm). Spring tension should be 9.1-11.1 lbs. (45 

N). 
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c. Replacement. 

 (1) Remove oil pressure regulating valve assembly, refer to step a. 

 (2) Replace spring (3) if found defective. 

 (3) For installation of oil pressure regulating valve assembly, refer to step d. 

d. Installation. 

 (1) Remove all covering installed during step a (4). 

 (2) Position oil pressure regulating valve (4, Figure 4-39) and spring (3) inside valve seat (5). Position 

washer (2) on plug (1). Install plug and torque to 70 lb-ft (95 Nm). 

4.5.3. OIL PAN.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

(1) Drain engine lubrication system, refer to TM 9-6115-672-14. 

 (2) If necessary, remove engine from generator set, refer to TM 9-6115-672-14. Mount engine on 

repair stand. Refer to paragraph 4.10. 

 (3) If necessary, remove oil dipstick assembly, refer to paragraph 3.11.5. 

 (4) Remove plugs/fittings (5, Figure 3-14) and O-ring gasket (6). 

 (5) Support oil pan (2) and remove capscrews (3 and 4), oil pan, and gasket (1). Discard gasket. 

 (6) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Remove oil pan (2, Figure 3-14), refer to step a. 

(2) Inspect oil pan (2) for cracks, dents, or other signs of damage. Replace per step c., as necessary. 

 (3) Inspect plugs/fittings (5) and hole for damaged threads or signs of leakage. Repair or replace as 

necessary. 

 (4) Inspect oil pump pickup tube assembly (refer to paragraph 4.5.4) for clogging or damage. 

 (5) Install oil pan (2), refer to step d. 
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AIR FORCE TO 38G1-126-2 

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4-49 

c. Replacement. 

 (1) Remove oil pan (2, Figure 3-14), refer to step a. 

 (2) Inspect oil pan (2), refer to step b. Replace oil pan if cracks, dents, or other signs of damage are 

found during inspection. Refer to step d. for installation. 

d. Installation. 

 (1) Remove all covering installed during step a (6). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Apply Flexible Form-In-Place Gasket on oil pan rail where flywheel housing, front plate, and 

timing gear cover attach to cylinder block. 

 (4) Position gasket (1, Figure 3-14) and oil pan (2) on cylinder block. Install screws (3 and 4) and 

torque to 26 lb-ft (35 Nm). 

 (5) If engine was removed from vehicle or machinery, install engine, refer to TM 9-6115-672-14. 

 (6) Install aluminum or copper washers on drain plugs (5) with raised center against plug. Install 

plugs in oil pan and torque to 35 lb-ft (47 Nm). Install fittings as required. 

 (7) Service engine lubrication system, refer to TM 9-6115-672-14. 

4.5.4 PICK-UP TUBE ASSEMBLY

a. Inspection.

 Inspect pick-up tube assembly for clogging or damage. Refer to Figure 4-40. 

FIGURE 4-40 PICK-UP TUBE ASSEMBLY 
ARMY TM 9-2815-260-24 

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4-50 

4.6. FUEL SYSTEM MAINTENANCE

__________ 

WARNING

Escaping diesel or JP fuel under pressure can have sufficient force to 

penetrate the skin, causing serious injury or death. Before disconnecting 

fuel lines, be sure to relieve pressure. Before applying pressure to the 

system, be sure all connections are tight and lines, pipes, and hoses are not 

damaged. Keep hands and body away from pinholes and nozzles which 

eject fuel under pressure. Use a piece of cardboard or wood, rather than 

hands, to search for suspected leaks. 

__________ 

WARNING

If diesel or JP fuel is injected into skin, seek medical attention immediately. 

 Failure to comply can result in serious injury. 

4.6.1. FUEL INJECTION PUMP.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

NOTE 

If working on fuel injection pump on TQG, refer to TM 9-6115-672-14 for 

removal and installation procedure for electrical actuator. 

a. Removal. 

 (1) Disconnect negative cable from batteries. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________ 

WARNING

Care should be exercised when using steam for cleaning. Steam is 

extremely hot. Skin and eye protection are required. Avoid contact with 

steam. 
ARMY TM 9-2815-260-24 

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4-51 

CAUTION

Fuel injection pump gets very hot during operation. Never steam clean or 

pour water on fuel injection pump while fuel injection pump is running or 

warm. Failure to comply could cause seizure of internal rotating parts. 

CAUTION

Dirt in the fuel system can damage components or cause poor engine 

performance. Always thoroughly clean the area around connection before 

disconnecting. Always cover all openings after disconnecting. Failure to 

comply can cause damage to components or poor engine performance. 

 (2) Thoroughly clean outside surface of fuel injection pump, fuel lines, and surrounding area with 

cleaning solvent or steam cleaner. 

 (3) Disconnect electrical connector mounted on top of pump which leads to governor. 

__________

WARNING

Diesel or JP fuel is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

NOTE 

Catch fuel in suitable container.

NOTE 

Disconnect all fuel delivery (pressure) lines from injection pump using a 

suitable 17 mm deep-well crowsfoot socket. 

 (4) Disconnect throttle cable from throttle arm (39). 

 (5) Disconnect fuel return line (3, Figure 3-17), fuel supply line (31), and fuel injection lines (7, 8, 9, 

10, 11 and 12). 

 (6) Remove capscrews (9, Figure 4-61), gear cover (8), and O-ring (7). Discard O-ring. 
ARMY TM 9-2815-260-24 

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CAUTION

Washer is small and easy to drop. Do not allow washer to fall inside timing 

gear cover. Failure to comply can cause damage to equipment when engine 

is started. 

 (7) Remove retaining nut (29, Figure 3-17) and washer (28) from end of pump shaft. 

 (8) Remove nut (23), washer (37), and lockwasher (38) from injection pump. 

 (9) Attach Drive Gear Puller (1, Figure 4-41) to injection pump drive gear (2). Evenly tighten screws 

(3) and snugly tighten center forcing screw (4) against end of pump shaft. 

 (10) Tighten center forcing screw (4, Figure 4-41) until pump drive gear (2) is free from tapered shaft. 

Remove Drive Gear Puller (1) from drive gear. 

LEGEND 

 1 DRIVE GEAR PULLER 

 2 INJECTION PUMP DRIVE GEAR 

 3 SCREW (2) 

 4 CENTER FORCING SCREW 

FIGURE 4-41. SEPARATING GEAR AND SHAFT 
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 (11) Check timing marks on back side of front plate (1, Figure 4-42) and injection pump flange (2). If 

timing marks are not aligned, or not clearly visible, scribe a visible reference mark in line with 

mark on pump flange. 

LEGEND 

 1 FRONT PLATE TIMING MARK 

 2 INJECTION PUMP FLANGE TIMING MARK 

 3 INJECTION PUMP MOUNTING FLANGE NUT 

Figure 4-42. CHECK TIMING MARKS 

 (12) Remove fuel injection pump (26, Figure 3-17), and sealing ring (32). Discard sealing ring. 

 (13) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Inspect all fuel lines for wear, kinks or fitting damage. Repair as necessary. 

NOTE 

Use a good light source to thoroughly inspect gear ID and shaft OD.

 (2) Inspect injection pump drive gear ID full 360° for metal transfer as a result of slippage on shaft 

 (3) Inspect injection pump drive shaft OD full 360° for presence of metal transfer from gear slippage. 

Also, check index pin in shaft for damage, indicating gear slippage. 

c. Replacement. 

 (1) Remove fuel injection pump, refer to step a. 

 (2) Perform inspection, refer to step b. Replace fuel injection pump if damaged. 

 (3) For fuel injection pump installation, refer to step e. 
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d. Installation. 

 (1) Remove all covering installed during step a (11). 

 (2) Lubricate sealing ring (32, Figure 3-17) with clean engine oil. Install sealing ring into groove on 

front face of fuel injection pump mounting flange. 

CAUTION

Index key is easily damaged if fuel injection pump is installed improperly. 

Insure that fuel injection pump shaft is properly aligned with pump drive 

gear. Pump drive gear should not move when initially installing shaft key 

into pump drive gear key slot. Failure to comply could result in damage to 

equipment. 

 (3) Align shaft key (25, Figure 3-17) pin on fuel injection pump shaft with pump drive gear key slot. 

Loosely position fuel injection pump on mounting studs while inserting pump shaft into drive gear. 

 (4) Check pump shaft and index pin for proper alignment with pump drive gear key slot. 

CAUTION

Index key is easily damaged if fuel injection pump is installed improperly. 

DO NOT tighten nuts more than three full turns on mounting studs. 

Failure to comply could result in damage to equipment. 

 (5) Position flat washers (37) and lock washers (38) on mounting studs (24). Position nuts (23) on 

mounting studs and tighten only three turns. 

CAUTION

Index key is easily damaged if fuel injection pump is installed improperly. 

DO not use tightening force of nuts (29) to pull pump shaft into drive gear. 

 (6) Position fuel injection pump mounting flange flush to engine front plate. Tighten mounting stud 

nuts (23) finger tight. 

 (7) Push pump drive gear firmly onto fuel injection pump shaft taper. Install washer and retaining nut. 

 Torque nut to 150 lb-ft (203 Nm). 

 (8) Position O-ring (7, Figure 4-61) and access cover plate (8) on front plate. Apply Thread Lock and 

Sealer (LOCTITE 242) to cap screw (9) threads. Install cap screws and torque to 17 lb-in (2 Nm). 

 (9) Align timing mark on fuel injection pump flange with timing mark on front plate. Torque nuts (3, 

Figure 4-42) to 20 lb-ft (27 Nm). 

 (10) Connect fuel injection pump pressure lines. Begin at outlet port for cylinder 1 (1, Figure 4-43) and 

continue around in counterclockwise direction, attaching lines in same order as engine firing (1-5-

3-6-2-4). Refer to Figure 4-43 for detailed view. 
ARMY TM 9-2815-260-24 

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CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (11) Torque fuel injection pump pressure lines to 20 lb-ft (27 Nm). 

 (12) Connect fuel supply line and torque to 22 lb-ft (30 Nm). 

FIGURE 4-43. FUEL INJECTION PUMP PRESSURE OUTLET PORTS 

 (13) Connect fuel return line and torque to 12 lb-ft (16 Nm). 

 (14) Connect electrical connector mounted on top of pump which leads to governor. 

 (15) Connect negative cable to batteries, refer to TM 9-6115-672-14. 

__________

WARNING

Operating the generator set with any access door open exposes personnel to 

high noise levels. Hearing protection must be worn when operating or 

working near the generator set with any access door open. Failure to 

comply can cause hearing damage or loss. 

 (16) Bleed fuel system, refer to paragraph 3.12.1. 

 (17) Start engine, refer to TM 9-6115-672-14, run for several minutes and check entire fuel system for 

leaks. Shut down engine. 
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4.6.2. FUEL INJECTION NOZZLE ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Pressure will not exceed 30psi (207 kPa). Eye protection 

required. 

CAUTION

Before removal, carefully remove all dirt from cylinder head around fuel 

injection nozzles. Clean with compressed air to prevent dirt from entering 

cylinders or valve seats. Plug bore in cylinder head after each fuel injection 

nozzle has been removed. Cap fuel line openings as soon as they are 

disconnected. 

CAUTION

Immediately fit protective caps over nozzle tips and line connections to 

avoid handling damage. 

(1) If removing only one fuel injection nozzle, loosen coupling nuts (2, Figure 3-17) and remove leak 

off line on each side of fuel injection nozzle. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (2) If removing all fuel injection nozzles, remove fuel leak-off line assembly, refer to paragraph 

3.12.4. 

 (3) Loosen coupling nut (2, Figure 3-17) and remove leak-off T-fitting (2, Figure 4-44) from each fuel 

injection nozzle (6) to be removed. Remove and discard washer (3). 

 (4) Disconnect fuel injection line from nozzle. Cap openings. 

 (5) Remove capscrew (5). 
ARMY TM 9-2815-260-24 

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CAUTION

Improper removal can damage fuel injection nozzle beyond repair. Do not 

use screwdrivers, pry bars, or similar tools to remove fuel injection nozzle. 

Failure to comply can cause damage to equipment. 

 (6) Pull fuel injection nozzle out of cylinder head using Injection Nozzle Puller Set or Adapter and 

slide handle from Puller Set. 

 (7) Remove washer (8, Figure 4-44) using razor blade or sharp knife. Discard washer. 

(8) Remove upper packing and discard. 

 (9) Cover all openings to prevent entry of foreign material. 

b. Test. 

 (1) Remove fuel injection nozzle, refer to step a. 

__________

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Pressure will not exceed 30 psi (207 kPa). Eye protection 

required. 

 (2) Prior to testing, clean the nozzles using the following procedures; 

 (a) Clean fuel injection nozzle bore with nozzle bore cleaning tool. Blow debris from bore 

with compressed air and plug bore to prevent entry of foreign material. 

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

 (b) Place fuel injection nozzle in solvent or clean diesel fuel and soak for several minutes. 

CAUTION

Do not scrape or disturb teflon coating on fuel injection nozzle body above 

washer groove. Do not use a steel wire brush, scraper, or motor-driven 

brush to clean nozzle body. Failure to comply could result in damage to 

fuel injection nozzle. 

NOTE 

Teflon coating will become discolored during normal operation, but this is 

not harmful. 
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4-58 

 (c) After soaking, clean fuel injection nozzle tip with brass wire brush (ROS16488) or 

equivalent. 

NOTE 

Insure that nozzle tester is in good condition and that gauge works 

properly. Service nozzle tester as recommended in operating instructions 

provided with tester. 

 (3) Connect fuel injection nozzle (6, Figure 4-44) to nozzle tester. 

__________

WARNING

Fuel from spray orifices can penetrate clothing and skin and cause serious 

personal injury. Always direct fuel injection nozzle tip away from 

personnel. Always enclose fuel injection nozzle in a transparent cover. 

Failure to comply could result in serious personal injury. 

__________

WARNING

If diesel or JP fuel is injected into skin, seek medical attention immediately. 

 Failure to comply can result in serious injury. 

 (4) Position tip of nozzle below top of beaker and back out 30 degrees from vertical. Leave 

connections slightly loose. 

 (5) Pump handle several strokes to flush air from lines and fittings and to determine pumping rate 

required for proper atomization. Tighten all connections securely after all air has been expelled 

from nozzle and line. 

 (6) Perform opening pressure test as indicated below: 

__________

WARNING

Fluid escaping from a very small hole can be almost invisible. Before 

applying pressure to nozzle tester, be sure that all connections are tight, and 

that fittings are not damaged. Use a piece of cardboard or wood to search 

for suspected leaks. Do not use hands to search for suspected leaks. Failure 

to comply could result in serious personal injury. 

 (a) Actuate nozzle tester rapidly several times to allow valve to seat rapidly. 

 (b) Open gauge valve and raise pressure to a point where gage needle falls rapidly. This is 

the nozzle opening pressure. Record nozzle opening pressure. 

 (c) Opening pressure should be at least 3,330 psi (22,950 kPa) for a used fuel injection 

nozzle and 3,660 psi (25,200 kPa) for a new fuel injection nozzle. Replace fuel injection 

nozzle if nozzle opening pressure is not within specified range. 
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4-59 

 (d) Opening pressure of all fuel injector nozzles on engine should be within 100 psi (700 

kPa) of each other. Replace any fuel injection nozzle that is not within specified limit. 

 (7) Perform chatter test as indicated below: 

NOTE 

Until chattering range is reached, fuel will emerge in non-atomized streams. 

 (a) Operate nozzle tester at a pumping rate that will cause fuel injection nozzle to chatter. 

FIGURE 4-44. FUEL INJECTION NOZZLE ASSEMBLY 
ARMY TM 9-2815-260-24 

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4-60 

 (b) Fuel injection nozzle should chatter softly, and spray pattern should be broad and finely 

atomized. Replace fuel injection nozzle if it fails to chatter. 

 (c) Using pumping rate for proper atomization, operate tester for ten strokes. Fuel injection 

nozzle must atomize on at least eight of the ten strokes without consecutive misses. If 

nozzle fails to meet requirement, repeat procedure. Replace fuel injection nozzle if it fails 

on second test. 

 (8) Perform spray pattern test as indicated below: 

 (a) Operate nozzle tester at a pumping rate that will cause fuel injection nozzle to chatter. 

 (b) Observe spray pattern of three orifices and check for plugged orifices. Replace fuel 

injection nozzle if spray pattern angle is incorrect or if spray pattern is streaky instead of 

finely atomized. 

 (9) Perform leakage test as indicated below: 

 (a) Position fuel injection nozzle on nozzle tester with nozzle tip down. 

 (b) Operate pump handle rapidly to firmly seat valve. Wipe nozzle tip dry with a clean, lint 

free cloth. 

 (c) Slowly raise pressure on test gauge to 400-500 psi (2800-3500 kPa) below opening 

pressure measured in step 5. 

 (d) Watch for accumulation of fuel around all three fuel injection nozzle tip orifices. Replace 

fuel injection nozzle if fuel drips from fuel injection nozzle within 5 seconds. 

 (10) Perform valve stem and guide wear test as indicated below: 

__________

WARNING

Fuel from spray orifices can penetrate clothing and skin and cause serious 

personal injury. Always direct fuel injection nozzle tip away from 

personnel. Always enclose fuel injection nozzle in a transparent cover. 

Failure to comply could result in serious personal injury. 

 (a) Position fuel injection nozzle with tip slightly above horizontal plane. 

 (b) Slowly raise pressure on test gauge to 1500 psi (10300 kPa). 

NOTE 

Leakage rate based on use of No. 2 diesel fuel or an equivalent viscosity of 

test oil at 65 to 75° F (18 to 24° C). 

 (c) Check for leakage from return end of fuel injection nozzle. After one drop, leakage 

should be 3-10 drops in 30 seconds. Replace fuel injection nozzle if not within specified 

range. 
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4-61 

c. Replacement. 

 (1) Remove fuel injection nozzle assembly, refer to step a. 

 (2) Test fuel injection nozzle assembly, refer to step b. Replace any nozzle that does not perform 

within specifications. 

 (3) For installation of fuel injection nozzle, refer to step d. 

d. Installation. 

 (1) Remove plug installed during step a. from nozzle bore in cylinder head and blow out bore with 

compressed air. 

NOTE 

Dirt or damage on the sealing surface of cylinder head (where fuel injection 

nozzle seal washer will be resting) can result in poor engine performance. 

Make sure that sealing surface of cylinder head is smooth and free from 

damage and dirt. Damage or dirt could prevent proper sealing or cause 

distortion to nozzle when attaching bolt is tightened. 

 (2) Thoroughly clean sealing surface of cylinder head, where washer (8, Figure 4-44) will be resting, 

and insure that sealing surface is free of damage. Repair or replace as required. 

 (3) Position new upper sealing washer (8) and packing (7) on fuel injection nozzle (6). 

 (4) Install fuel injection nozzle (6) in cylinder head using a slight twisting motion as fuel injection 

nozzle is seated in bore. Insure that fuel injection nozzle is installed in the proper orientation. 

 (5) Align hold-down clamps (9, Figure 4-44) and install capscrew (5) finger tight. 

 (6) Remove caps and connect fuel pressure line to fuel injection nozzle (6). Torque connection to 20 

lb-ft (27 Nm). 

 (7) Tighten capscrew (5) to 30 lb-ft (40 Nm). 

 (8) Position washer (3), leak-off T-fitting (2) and tube nut (4) on fuel injection nozzle (6). 

 (9) Install leak-off line assembly, refer to paragraph 3.12.4. 

 (10) Torque coupling nut (2, Figure 3-17) to 20 lb-ft (27 Nm). 

 (11) Bleed air from fuel injection system, refer to paragraph 3.12.1. 
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4.6.3. FUEL FILTER BASE.

a. Removal. 

 (1) Remove fuel filter element, refer to paragraph 3.12.2. 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (2) Remove fuel line (6, Figure 3-15) and disconnect fuel line (7). 

 (3) Remove capscrews (8) and fuel filter base (9). 

 (4) Cover all openings to prevent entry of foreign material. 

b. Repair. 

NOTE 

Repair of this item is limited to the replacement of the O-rings only. 

 (1) Remove plugs (10 and 11, Figure 3-15) and O-ring seals (12). Discard O-ring seals. 

 (2) Remove connectors (13) and O-ring seals (12). Discard O-ring seals. 

 (3) Remove air bleed vent screw (14) and O-ring seal (15). 

 (4) Remove retaining ring (16), cap (17), O-ring seal (18), plunger (19) and plunger housing (20). 

Discard O-ring seal. 

 (5) Inspect fuel filter base (9, Figure 3-15) for cracks or other damage. Replace if necessary. 

 (6) Position plunger housing (20, Figure 3-15), plunger (19), O-ring seal (18) and cap (17) in fuel 

filter base (9). Install retaining ring (16) hand tight. 

 (7) Position O-ring seal (15) on air bleed vent screw (14) and install air bleed vent screw hand tight. 

 (8) Position O-ring seals (12) on connectors (13) and install connectors. 

 (9) Position O-ring seals (12) on plugs (10 and 11) and install plugs. 

c. Installation. 

 (1) Remove all covering installed during step a (4). 

 (2) Position fuel filter base (9, Figure 3-15) on cylinder head. Install capscrews (8) and torque evenly 

to 26 lb-ft (35 Nm). 
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CAUTION

Thread sealant can cause damage to fuel system. Do not allow sealant to 

get into fuel system. Failure to comply could result in damage to fuel 

system. 

 (3) Apply Thread Lock and Sealer (LOCTITE 242) to threads of fuel lines (6 and 7). 

CAUTION

Fuel lines are fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

 (4) Connect fuel line (7) and install fuel line (6). 

 (5) Install fuel filter element, refer to paragraph 3.12.2. 

 (6) Bleed fuel system, refer to paragraph 3.12.1. 

4.7. CYLINDER HEAD ASSEMBLY MAINTENANCE

4.7.1. ROCKER ARM COVER.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

 (1) Remove plugs (2 and 6, Figure 4-45), nuts (3), O-ring seals (4), rocker arm cover (7) and gasket 

(5). Discard O-ring seals and gasket. 

 (2) Cover all openings to prevent entry of foreign material. 

b. Replacement.

Remove rocker arm cover, refer to step a. Replace cover if bent or damaged. For installation, refer to step 

c. 
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4-64 

c. Installation.

 (1) Remove all covering installed during step a (2). 

CAUTION

Do not use any cutting tool to remove gasket material from rocker arm 

cover. Failure to comply could result in damage to rocker arm cover. 

 (2) Insure all gasket material is removed from sealing surfaces. 

NOTE 

Do not use sealant on gasket

 (3) Position new gasket (5, Figure 4-45) on rocker arm cover (7). 

CAUTION

Do not overtighten nuts. Failure to comply could result in damage to gasket 

and loss of lubrication oil. 

 (4) Position rocker arm cover (7) on cylinder head. Install O-ring seals (4) and nuts (3). Torque nuts 

to 26 lb-ft (35 Nm), starting at center of rocker arm cover and alternating sides until reaching ends. 

 (5) Install plugs (2) and (6). 

4.7.2. INTAKE AND EXHAUST VALVE CHECKS AND ADJUSTMENTS.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Adjust.

NOTE 

Setting engine with No. 1 Piston at TDC Compression stroke is required in 

many different maintenance steps and is not a stand alone maintenance 

procedure. 

 (1) Set Engine with No. 1 Piston at TDC (Top Dead Center) Compression Stroke. 
ARMY TM 9-2815-260-24 

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FIGURE 4-45. ROCKER ARM COVER. 

(a) Remove rocker arm cover, refer to paragraph 4.7.1. 

 (b) Remove cover plate from timing hole (1, Figure 4-46). 

 (c) Position timing pin in timing hole (2). 

 (d) Position flywheel rotation tool in hole (2) and insure that tool meshes with flywheel gear. 

NOTE 

Rotate engine flywheel clockwise when viewed from the front of the engine. 

 (e) Apply light pressure to tip of timing pin and rotate flywheel rotation tool 

counterclockwise until timing pin slides into hole in flywheel and prevents flywheel from 

turning. 
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FIGURE 4-46. ENGINE TIMING HOLE LOCATION 

 (f) Check rocker arms on Number 1 cylinder, refer to Figure 4-47. If both rocker arms are 

loose, the engine is set with No. 1 Piston at TDC. If both rocker arms are not loose, 

engine is one full revolution (360°) away from TDC, rotate engine slightly and repeat 

steps c and d. 

 (2) Set Engine with No. 6 Piston at TDC Compression Stroke. 

NOTE 

Setting engine with No. 6 Piston at TDC Compression stroke is required in 

many different maintenance steps and is not a stand alone maintenance 

procedure. 

 (a) Remove rocker arm cover, refer to paragraph 4.7.1. 

 (b) Remove cover plate from timing hole (1, Figure 4-46). 

 (c) Position timing pin (JDE81-4) in timing hole (1, Figure 4-46). 

 (d) Position flywheel rotation tool (JDG820) in hole (2) and insure that tool meshes with 

flywheel gear. 
ARMY TM 9-2815-260-24 

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NOTE 

Rotate engine flywheel clockwise when viewed from the front of the engine. 

 (e) Apply light pressure to tip of timing pin and rotate flywheel rotation tool 

counterclockwise until timing pin slides into hole in flywheel and prevents flywheel from 

turning. 

 (f) Check rocker arms on Number 6 cylinder, refer to Figure 4-47. If both rocker arms are 

loose, the engine is set with No. 6 Piston at TDC. If both rocker arms are not loose, 

engine is one full revolution (360°) away from TDC, rotate engine slightly and repeat 

steps 4 and 5. 

b. Test Valve Clearance.

 (1) Check and Adjust Valve Clearance. 

NOTE 

Valve clearance MUST BE checked and adjusted with engine COLD. 

 (a) Remove rocker arm cover, refer to paragraph 4.7.1. 

 (b) Visually inspect contact surfaces of valve tips and rocker arm wear pads. Check all parts 

for excessive wear. Replace all parts that show visible damage. 

FIGURE 4-47. ROCKER ARM LOCATION 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

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NOTE 

Firing order is 1-5-3-6-2-4.

 (2) Set engine with No. 1 cylinder at TDC compression stroke. 

 (3) Check valve clearance on No. 1, 3, and 5 exhaust valves and No. 1, 2, and 4 intake valves per 

specifications in Table 4-2. If valve clearance exceeds specifications, thoroughly inspect rocker 

arms for damaged parts. If required, adjust per step 4. 

 (4) Loosen jam nut (8, Figure 4-48) and adjust valve clearance on No. 1, 3, and 5 exhaust valves and 

No. 1, 2, and 4 intake valves to specifications given in Table 4-2. Torque jam nut to 20 lb-ft (27 

Nm). Verify valve clearance and adjust again if necessary. 

Table 4-2. Valve Clearance Specification (Rocker Arm-To-Valve Tip)

Item Specification 

Intake Valves 0.014 in. (0.35 mm) 

Exhaust Valves 0.018 in. (0.045 mm) 

 (5) Set engine with No. 6 cylinder at TDC compression stroke. 

 (6) Check valve clearance on No. 2, 4, and 6 exhaust valves and No. 3, 5, and 6 intake valves per 

specifications in Table 4-2. If valve clearance exceeds specifications, thoroughly inspect rocker 

arms for damaged parts. If required, adjust per step 7. 

 (7) Loosen jam nut (8, Figure 4-48) and adjust valve clearance on No. 2, 4, and 6 exhaust valves and 

No. 3, 5, and 6 intake valves to specifications given in Table 4-2. Torque jam nut to 20 lb-ft (27 

Nm). Verify valve clearance and adjust again if necessary. 

 (8) Install rocker arm cover, refer to paragraph 4.7.1. 

c. Test Valve Lift. 

 (1) Remove rocker arm cover, refer to paragraph 4.7.1. 

 (2) Visually inspect contact surfaces of valve tips and rocker arm wear pads. Check all parts for 

excessive wear. Replace all parts that show visible damage. 

 (3) Set engine with No. 1 piston at TDC compression stroke, refer to step a. 

 (4) Loosen jam nut (8, Figure 4-48) and adjust valve clearance on No. 1, 3, and 5 exhaust valves and 

No. 1, 2, and 4 intake valves to 0.00 in. (mm). Torque jam nut to 20 lb-ft (27 Nm). 

 (5) Position dial indicator tip on top of No. 1 exhaust valve spring cap. 

 (6) Preload dial indicator tip and set dial at 0.00 in. (mm). 
ARMY TM 9-2815-260-24 

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 (7) Remove timing pin from flywheel and manually rotate engine one full revolution (360°) in running 

direction (clockwise when viewed from front of engine) using (JDG820) flywheel turning tool. 

 (8) Observe dial indicator reading as valve is moved to full open. Record maximum reading and 

compare with specifications given in Table 4-3. 

 (9) Repeat steps 5 through 8 for remaining valves. 

 

 (10) Set engine with No. 6 piston at TDC compression stroke, refer to step a. 

 (11) Loosen jam nut (8) and adjust valve clearance on No. 2, 4, and 6 exhaust valves and No. 3, 5, and 

6 intake valves to 0.00 in. (mm). Torque jam nut to 20 lb-ft (27 Nm). 

 (12) Position dial indicator tip on top of No. 2 exhaust valve spring cap. 

 (13) Preload dial indicator tip and set dial at 0.00 in. (mm). 

 (14) Remove timing pin from flywheel and manually rotate engine one full revolution (360°) in running 

direction (clockwise when viewed from front of engine) using (JDG820) flywheel turning tool. 

 (15) Observe dial indicator reading as valve is moved to full open. Record maximum reading and 

compare with specifications given in Table 4-3. 

 (16) Repeat steps 12 through 15 for remaining valves. 

 (17) If valve lift on all valves is within specifications given in Table 4-3, check and adjust valve 

clearance, refer to paragraph b. 

 (18) If valve lift on one or more valves is not within specifications given in Table 4-3, notify next 

higher maintenance level to remove and inspect entire valve train and camshaft. 

Table 4-3. Valve Lift Specification at 0.00 in. (mm) Valve Clearance

Item Specification 

Intake Valves 0.455 - 0.487 in. (11.56 - 12.37 mm) 

Exhaust Valves 0.444 - 0.477 in. (11.28 - 12.12 mm) 
ARMY TM 9-2815-260-24 

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4.7.3. ROCKER ARM ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 (1) Remove rocker arm cover, refer to paragraph 4.7.1. 

FIGURE 4-48. ROCKER ARM ASSEMBLY. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

4-71 

CAUTION

Support studs must be loosened sequentially, a little at a time, to prevent 

warping of shaft. 

 (2) Remove support studs (5, Figure 4-48), washers (6) and remainder of rocker arm assembly. 

 (3) Remove push rods (11) and tag push rods as to their location. 

 (4) Cover all openings to prevent entry of foreign material. 

b. Adjust.

 For valve adjustment, refer to paragraph 4.7.2. 

c. Repair. 

 (1) Remove rocker arm assembly (refer to step a.) and place on a suitable workbench. 

NOTE 

Note locations and tag parts as they are removed.

 (2) Remove end plugs (1, Figure 4-48), washers (3), rocker arms (9), supports (7) and springs (4) from 

rocker arm shaft (2). Discard end plugs. 

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin/eye protection required. Avoid repeated/prolonged contact. Provide 

adequate ventilation. Failure to comply could result in serious injury or 

death. 

__________

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

 (3) Thoroughly clean all rocker arm assembly components and push rods (11, Figure 4-48) with dry 

cleaning solvent. Dry with compressed air. 

 (4) Inspect parts for cracks or obvious signs of damage. Replace as necessary. 

 (5) Measure springs (4) with spring tester (DO1168AA) by applying force to spring until spring is 

compressed to a length of 1.81 in. (46 mm). Spring tension should be 4 - 6 lbs. (18 - 27 N). 

Replace any spring not within specifications. 
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 (6) Inspect rocker arm shaft (2) for severe scratching, scoring, or excessive wear at points of rocker 

arm contact. Roll rocker arm shaft on a flat surface to check for bends or distortion. Replace as 

necessary. 

 (7) Measure OD of rocker arm shaft (2) with OD micrometer. Rocker arm shaft OD should be 0.787 - 

0.788 in. (19.99 - 20.02 mm). Replace rocker arm shaft if not within specifications. 

 (8) Measure ID of supports (7) with ID micrometer. Support ID should be 0.794 in. (20.17 mm) 

maximum. Replace any support not within specifications. 

 (9) Inspect adjusting screw on rocker arm (9) and jam nut (8) for damage. Visually inspect rocker arm 

for hairline cracks. Replace as necessary. 

 (10) Inspect for cups or concave wear on ends of rocker arms (9) where rocker arms contact valve tips. 

If wear exists, replace rocker arm. 

 (11) Measure ID of rocker arm (9) bore with ID micrometer. Rocker arm bore ID should be 0.790 - 

0.792 in. (20.07 - 20.12 mm). Replace any rocker arm not within specifications. 

 (12) Inspect push rods (11) for wear, damage, or physical distortion. Roll push rods on a flat surface to 

check for bends or distortion. Replace as necessary. 

 (13) For assembly, lubricate OD of rocker arm shaft (2, Figure 4-48), bores of rocker arms (9) and 

supports (7) with clean engine lubricating oil (MIL-L-2104). 

CAUTION

Oil supply hole on rocker arm shaft must be toward flywheel end of engine. 

 Failure to comply could result in damage to engine. 

NOTE 

Assemble parts in same locations from which they were removed. 

 (14) Position rocker arms (9), supports (7), springs (4) and washers (3) on rocker arm shaft (2). Install 

new end plugs (1). End plugs must be firmly seated against end of shaft. 

d. Replacement. 

 (1) Remove rocker arm assembly, refer to step a. 

 (2) Perform repair procedures, refer to step c. Replace any components that are not within 

specifications. 

 (3) For installation, refer to step e. 
ARMY TM 9-2815-260-24 

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e. Installation. 

 (1) Remove all covering installed during step a (4). 

 (2) Install push rods (1, Figure 4-48) in same locations from which they were removed. 

 (3) Position rocker arm assembly on engine. 

 (4) Lubricate all rocker arms (9) with MIL-L-2104 engine lubricating oil. Insure that rocker arms 

move freely. 

 (5) Position supports (7) and washers (6) on cylinder head. Install support studs and torque evenly, a 

little at a time, to 59 lb-ft (80 Nm). 

 (6) Adjust valve clearance. Refer to paragraph 4.7.2. 

4.7.4. CYLINDER HEAD.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal. 

 (1) Disconnect negative cable from battery, refer to TM 9-6115-672-14. 

 (2) Drain engine coolant system, refer to TM 9-6115-672-14. 

 (3) Remove air intake and exhaust system, refer to TM 9-6115-672-14. 

 (4) Remove turbocharger, refer to paragraph 4.4.1 

 (5) Remove intake manifold, refer to paragraph 4.4.2. 

 (6) Remove exhaust manifold, refer to paragraph 4.4.3. 

 (7) Remove thermostat housing and thermostat housing to water pump tube, refer to paragraph 3.8.2. 

 (8) Remove fuel filter, refer to paragraph 3.12.2. 

 (9) Remove fuel transfer lines, refer to paragraph 3.12.3. 

 (10) Remove fuel injection lines, refer to paragraph 3.12.4. 

 (11) Remove fuel injection nozzles, refer to paragraph 4.6.2. 

 (12) Remove rocker arm cover, refer to paragraph 4.7.1. 
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 (13) Remove rocker arm assembly and push rods, refer to paragraph 4.7.3. 

 (14) If a blown head gasket (12, Figure 4-49) is suspected, check and record torque on each capscrew 

(1) on cylinder head (14) before removing as follows: 

 (a) Make a reference mark (in-line) on head of capscrew (1) (or socket) and cylinder head 

surface. 

 (b) Loosen capscrew at least 1⁄2 turn, then retighten capscrew (using a torque wrench) until 

reference marks align and record torque. 

 (c) If capscrews are not tightened to 110 lb-ft (150Nm), retorque to 110 lb-ft (150Nm) per 

step g. and retest engine. 

 (15) Remove all cylinder head capscrews (1). 

CAUTION

Do not use screwdrivers or pry bars between cylinder block and cylinder 

head to loosen cylinder head gasket seal. Screwdrivers or pry bars can 

damage cylinder head and cylinder block gasket surfaces. 

CAUTION

Do not rotate crankshaft with cylinder head removed unless cylinder liners 

are secured with cap screws and large flat washers, refer to paragraph 

5.4.5. 

 (16) Using adequate lifting device, lift cylinder head (14) from cylinder block. If cylinder head sticks, 

use a soft hammer to tap cylinder head. 

 (17) Remove cylinder head gasket (12). Inspect cylinder head gasket for possible oil, coolant, or 

combustion chamber leaks. Discard cylinder head gasket. 
ARMY TM 9-2815-260-24 

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FIGURE 4-49. CYLINDER HEAD ASSEMBLY. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

4-76 

 (18) Remove fuel supply pump push rod. Label end for reassembly in same orientation. Refer to 

Figure 4-50. 

FIGURE 4-50. FUEL TRANSFER PUMP PUSH ROD LOCATION 

 (19) Cover all openings to prevent entry of foreign material. 

b. Inspection. 

 (1) Measure and record valve recess (Figure 4-51) for all valves using a depth micrometer or magnetic 

base dial indicator. Measurements must be made a maximum of 0.12 in. (3.0 mm) from edge of 

valve head. 

FIGURE 4-51. VALVE RECESS MEASUREMENT 
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 (2) Compare valve recess measurements for all valves to specifications given in Table 4-4. Install new 

valves, inserts, or grind existing valves and inserts, as necessary, to obtain proper valve recess. 

Table 4-4. Valve Recess Specifications

Item Specification 

Intake Valves (new or rebuilt) 0.024 - 0.044 in. (0.61 - 1.11 mm) 

Intake Valves (worn) 0.024 - 0.064 in. (0.61 - 1.63 mm) 

Exhaust Valves (new or rebuilt) 0.048 - 0.068 in. (1.22 - 1.72 mm) 

Exhaust Valves (worn) 0.048 - 0.089 in. (1.22 - 2.26 mm) 

 (3) If valve recess is not within specifications, install new valves or valve seat inserts, or grind existing 

valves and valve seat inserts, to obtain proper valve recess. 

c. Testing Prior to Installation. 

 (1) Clean and inspect cylinder head cap screws as follows: 

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

 (a) Clean entire length of cap screws. Use wire brush and solvent to remove rust and scale. 

Dry cap screws with compressed air. 

 (b) Inspect cap screws for corrosion damage and overall condition of threads. Cap screws 

with corrosion or other imperfections must be replaced. 

 (2) Clean and inspect top deck of cylinder block as follows: 

 (a) Remove gasket material, rust, carbon, and other foreign material from top deck of 

cylinder block. Gasket surface must be clean. 

 

 (b) Clean threaded holes in cylinder block using 1⁄2-13 UNC-2A tap about 3.0 in. (76 mm) 

long. Use compressed air to remove debris and fluids from cap screw holes. Replace 

block if there is evidence of damage. 
ARMY TM 9-2815-260-24 

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 (c) Use compressed air to remove all loose foreign material from cylinders and top deck of 

cylinder block. 

 (d) Remove camshaft followers from cylinder block and wash in solvent. Lubricate with 

clean engine oil and install in same bore. 

 (e) Measure cylinder block top deck flatness using precision straightedge (DO5012ST) and 

feeler gauge. Compare measurements with specifications given in Table 4-5. If flatness 

is not within specifications notify next higher maintenance level. 

 (3) Inspect fuel supply pump push rod and bore as follows: 

 (a) Measure OD of fuel transfer pump push rod with OD micrometer. Fuel supply pump 

push rod OD should be 0.3894 - 0.3904 in. (9.891 - 9.917 mm). Replace fuel supply 

pump push rod if not within specifications. 

 (b) Check crown on fuel supply pump push rod ends. If crown is flat or concave, replace fuel 

supply pump push rod and notify next higher maintenance level to check camshaft lobe 

for wear. 

 (c) Measure ID of fuel supply pump push rod bore with ID micrometer. Fuel supply pump 

push rod bore should be 0.3937 - 0.3957 in. (9.891 - 9.917 mm). Repair or replace block 

as necessary. 

Table 4-5. Cylinder Block Top Deck Specifications 

Item Specification 

Maximum Acceptable Out-of-Flat: 

 Entire Length or Width 0.003 in. (0.025 mm) 

 Any 5.90 in. (150 mm) Length 0.001 in. (0.025 mm) 

d Installation. 

 (1) Remove all covering installed during step a (19). 

 (2) Ensure all old gasket material is removed from gasket surfaces. 

 (3) Lubricate fuel supply pump push rod with clean engine oil and install in same orientation as 

removed from in step a. 

 (4) Install two guide studs in cylinder block at locating holes 16 and 17 shown in Figure 4-52. 

CAUTION

Thoroughly inspect new cylinder head gasket for possible manufacturing 

imperfections. Do not install any gasket that does not pass inspection. 

Failure to comply could result in cylinder head gasket failure. 
ARMY TM 9-2815-260-24 

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4-79 

 (5) Position new cylinder head gasket on cylinder block. Do not use sealant; install dry. 

CAUTION

O-Ring seals in head gasket can be damaged if head is repositioned while 

resting on engine block. Always use guide studs to position cylinder head 

on block. Failure to comply could result in cylinder head gasket failure. 

 (6) Using adequate lifting device, position cylinder head over guide studs and carefully lower cylinder 

head onto cylinder block. 

NOTE 

Prior to installing capscrews in cylinder block, dip entire capscrew in clean 

engine oil. Remove excess oil from capscrew. 

 (7) Install several capscrews (1, Figure 4-49) finger tight. Remove guide studs. Install remaining 

capscrews finger tight. 

 (8) Tighten all capscrews (1) in sequence shown in Figure 4-52, beginning with No. 1, to 75 lb-ft (100 

Nm). 

 (9) Using the same sequence repeat step 8, this time tightening all capscrews (1) to 110 lb-ft (150 

Nm). 

FIGURE 4-52. CYLINDER HEAD CAPSCREW TORQUE SEQUENCE 
ARMY TM 9-2815-260-24 

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4-80 

 (10) Wait 5 minutes, then verify 110 lb-ft (150 Nm) torque on all capscrews (1, Figure 4-49). Tighten 

capscrews as required. 

 (11) Repeat step 9, this time tightening all capscrews (1) an additional 1/6 turn, as described below: 

 (a) Make a mark on socket and make a second mark 1/6 turn (one wrench flat) 

counterclockwise of first mark, when viewed from top of socket. 

 (b) Place socket on capscrew and make a mark on cylinder head adjacent with first mark on 

socket. 

 (c) Tighten capscrew until second mark aligns with mark on cylinder head. 

 (12) Install push rods and rocker arm assembly, refer to paragraph 4.7.3. 

 (13) Adjust valve clearance, refer to paragraph 4.7.2. 

 (14) Install valve cover, refer to paragraph 4.7.1. 

 (15) Install fuel injection nozzles, refer to paragraph 4.6.2. 

 (16) Install fuel injection lines, refer to paragraph 3.12.4. 

 (17) Install fuel filter, refer to paragraph 3.12.2. 

 (18) Install thermostat housing and thermostat housing to water pump tube, refer to paragraph 3.8.2. 

 (19) Install exhaust manifold, refer to paragraph 4.4.3. 

 (20) Install intake manifold, refer to paragraph 4.4.2. 

 (21) Install turbocharger, refer to paragraph 4.4.1. 

 (22) Install air intake and exhaust system, refer to TM 9-6115-672-14. 

 (23) Connect negative cable to battery, refer to TM 9-6115-672-14. 

 (24) Service lubrication and coolant systems, refer to TM 9-6115-672-14. 

 (25) Start engine, refer to TM 9-6115-672-14. 

 (26) Run engine at no load for one minute. Shut down engine and check for fuel, coolant and oil leaks. 

 Correct as required. 

 (27) Start engine, refer to TM 9-6115-672-14. 

 (28) Run engine at load for 10 minutes. Shut down engine and allow to cool. 

 (29) Recheck valve clearances and adjust, as necessary, refer to paragraph 4.7.2. 
ARMY TM 9-2815-260-24 

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4.8. FLYWHEEL AND HOUSING ASSEMBLY MAINTENANCE

4.8.1. FLYWHEEL.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Inspection. 

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

 (1) Thoroughly clean flywheel with solvent and dry with compressed air. 

 (2) Inspect flywheel for rust, corrosion, cracks, or other forms of damage. Clean or replace as 

required. 

 (3) Inspect ring gear (2, Figure 4-55) for worn or broken teeth. Replace ring gear if damaged, refer to 

4.8.1.c. 

 (4) Check flywheel face flatness as follows: 

CAUTION

Do not allow dial indicator to contact driving ring mounting holes. Failure 

to comply could result in damage to dial indicator. 

 (a) Attach magnetic base of dial indicator to flywheel housing (Figure 4-53). Position dial 

indicator against driving ring mounting surface on flywheel. 

 (b) Rotate flywheel by turning crankshaft. Read total indicator movement and compare with 

specifications given in Table 4-6. Replace as required. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

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FIGURE 4-53 FLYWHEEL FLATNESS 

Table 4-6. Flywheel Face Flatness Specifications 

Item Specification 

Maximum variation 0.009 in. (0.23 mm) 

Maximum variation per 1.0 in. (25 mm) of 

travel 

0.0005 in. (0.013 mm) 

b. Removal. 

__________

WARNING

Flywheel is heavy. Provide adequate lifting device to support weight. 

Failure to comply could result in serious personal injury. 

 (1) Remove bolts (Figure 4-54). 

FIGURE 4-54. FLYWHEEL REMOVAL 
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 (2) Remove flywheel. 

c. Replacement. 

 (1) Before removal, perform inspection (paragraph 4.8.1.a) of flywheel and ring gear while mounted 

to engine. Replace flywheel if damaged. 

 (2) For installation of flywheel, refer to 4.8.1.d. 

FIGURE 4-55 FLYWHEEL RING GEAR 

d. Installation. 

__________

WARNING

Flywheel is heavy. Provide adequate lifting device to support weight. 

Failure to comply could result in serious personal injury. 

 (1) Place flywheel on guidestud and slide into position against crankshaft. 

 (2) Apply Thread Lock (Appendix E) to threads of all bolts and finger tighten. Torque all bolts to 102 

lb-ft (138 Nm). 
ARMY TM 9-2815-260-24 

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4.8.2. REAR CRANKSHAFT OIL SEAL/WEAR SLEEVE ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

 (1) Remove flywheel, refer to paragraph 4.8.1. 

 (2) Adjust forcing screw (1, Figure 4-56) on Seal and Wear Sleeve Remover and position screw so 

screw centers tool on crankshaft flange. 

FIGURE 4-56. REMOVAL OF REAR CRANKSHAFT OIL SEAL 

CAUTION

Do not remove seal and wear sleeve assembly from plastic bag until 

immediately before installing. Failure to comply could result in dirt 

contamination and premature seal failure. 

 (3) Use slots in Seal and Wear Sleeve Remover as a template and mark three locations on seal casing 

where screws should be installed for removal purposes. Remove tool from crankshaft flange. 
ARMY TM 9-2815-260-24 

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NOTE 

Holes must be drilled at outer edge of seal case so screws will pull seal 

against wear ring and allow both pieces to be removed. 

 (4) Drill a 5/32 in. hole through wear sleeve lip and seal casing at all three marked locations. 

 (5) Position Seal and Wear Sleeve Remover on end of crankshaft. 

 (6) Install three 2 1⁄2 in. sheet metal screws (2, Figure 4-56) with washers into slots of removal tool and 

thread screws into holes in seal casing. Evenly tighten screws until plate is flush with rear face of 

crankshaft. 

 (7) Tighten forcing screw until seal and wear sleeve assembly is removed from engine. 

 (8) Discard seal and wear sleeve assembly. 

 (9) Cover all openings to prevent entry of foreign material. 

b. Inspection.

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

 (1) Thoroughly clean outer diameter of crankshaft flange and inner diameter of flywheel housing with 

cleaning solvent. 

 (2) Inspect wear ring surface and bore in flywheel housing for nicks or burrs. Remove nicks or burrs 

with polishing cloth, as required. 

 (3) Check flywheel housing seal bore run out as follows: 

 (a) Attach magnetic base of dial indicator to flywheel end of crankshaft. 

 (b) Position dial indicator against inner diameter of seal bore in flywheel housing and zero 

dial indicator. 

 (c) Turn crankshaft 360 degrees from front of engine while observing dial indicator. 

Maximum permissible run out of flywheel housing seal bore is 0.006 in. (0.0152 mm). 

Replace flywheel housing if run out exceeds specification. 

c. Replacement.

The rear crankshaft oil seal must be replaced if any liquid is present during visual inspection. Refer to 

4.8.2.a for removal and 4.8.2.d for installation. 
ARMY TM 9-2815-260-24 

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d. Installation. 

 (1) Remove all covering installed during 4.8.2.a(9). 

 (2) Clean outer diameter of crankshaft flange and inner diameter of wear sleeve with cleaning solvent 

(Appendix E). Apply light coating of retaining compound (Appendix E) completely around 

leading edge of crankshaft flange. Wipe away sealant that may have gotten on flywheel housing 

seal bore. 

 (3) Install Pilot on end of crankshaft using two socket head capscrews (Figure 4-58). Tighten both 

capscrews until capscrews touch base of pilot. Loosen capscrews 1⁄2 turn. 

FIGURE 4-57 REAR CRANKSHAFT OIL SEAL INSTALLATION 

 (4) Install driver over pilot until driver cross plate bottoms on pilot (Figure 4-58). If necessary, lift up 

on pilot to install driver to full depth over pilot and crankshaft flange. 

 (5) Tighten pilot socket head capscrews securely. Remove driver from pilot. 

CAUTION

Oil seal and wear sleeve are assembled. Do not separate. Failure to comply 

could result in damage to seal and loss of engine oil. 

 (6) Carefully inspect new oil seal and wear sleeve assembly. Discard and replace if seal is scratched 

or gouged, or if any liquid is present. 

 (7) Carefully slide oil seal and wear sleeve over pilot and crankshaft flange with open side of seal 

toward engine. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-87 

 (8) Attach Driver and thrust washer to guide plate with capscrew. Tighten capscrew until driver 

bottoms on pilot. 

 (9) Remove seal driver and pilot plate. Check that seal and wear sleeve assembly is properly 

positioned on crankshaft flange and installed evenly in flywheel housing bore. 

 (10) Install flywheel, refer to paragraph 4.8.1.d. 

4.8.3. FLYWHEEL HOUSING.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

 (1) Remove starter, refer to paragraph 4.3.2. 

 (2) Remove flywheel, refer to paragraph 4.8.1. 

 (3) Remove crankshaft rear oil seal and wear sleeve, refer to paragraph 4.8.2. 

__________

WARNING

Flywheel housing is heavy. Provide adequate lifting device to support 

weight. Failure to comply could result in serious personal injury. 

 (4) Remove bolt (4, Figure 4-58), bolt (6) and flywheel housing (1). 

 (5) Cover all openings to prevent entry of foreign material. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-88 

FIGURE 4-58. FLYWHEEL AND HOUSING ASSEMBLY 

b. Inspection.

 (1) Remove flywheel housing, refer to step 4.8.3.a. 

 (2) Thoroughly clean flywheel housing gasket surface using brass scraper. 

 (3) Inspect flywheel housing for cracks, corrosion, or other forms of damage. Repair or replace as 

required. 

 (4) Install flywheel housing, refer to step 4.8.3.d. 

c. Replacement.

 (1) Remove flywheel housing, refer to step 4.8.3.a. 

 (2) Inspect flywheel housing, refer to step 4.8.3.b. Replace if damaged. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-89 

 (3) Install flywheel housing, refer to step 4.8.3.d. 

d. Installation.

 (1) Remove all covering installed during step 4.8.3.a.(5). 

 (2) Insure all gasket material is removed from sealing surfaces. 

 (3) Apply Flexible Form-In-Place Gasket (Appendix E) in a continuous 0.06 - 0.08 in. (1.5 - 2 mm) 

thick bead (A) to cylinder block as shown in Figure 4-58. Ensure that sealant bead is located in 

center of mating surfaces and completely encircle bolt holes. 

 (4) Install two guide studs in bolt holes (Figure 4-60). 

__________

WARNING

Flywheel housing is heavy. Provide adequate lifting device to support 

weight. Failure to comply could result in serious personal injury. 

 (5) Using guide studs, position flywheel housing on cylinder block and install bolts finger tight. 

FIGURE 4-59. GASKET APPLICATION TO CYLINDER BLOCK 

 (6) Remove guide studs and install remaining bolts finger tight. Torque all attaching bolts, using a 

cross pattern, to 92 lb-ft (125 Nm). 

 (7) Check flywheel housing seal bore run out as follows: 

 (a) Attach magnetic base of dial indicator to flywheel end of crankshaft. 

 (b) Position dial indicator against inner diameter of seal bore in flywheel housing and zero 

dial indicator. 

 (c) Turn crankshaft 360 degrees from front of engine while observing dial indicator. 

Maximum permissible run out of flywheel housing seal bore is 0.006 in. (0.0152 mm). 

Replace flywheel housing if run out exceeds specification. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-90 

 (8) Install rear crankshaft oil seal/wear sleeve assembly, refer to paragraph 4.8.2. 

 (9) Install flywheel, refer to paragraph 4.8.1. 

4.9. CRANKSHAFT PULLEY, TORSIONAL DAMPER, AND TIMING GEAR COVER ASSEMBLY 

 MAINTENANCE

4.9.1. TORSIONAL DAMPER.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Inspection.

 (1) Visually inspect torsional damper for damaged, separated, or partially missing rubber. If rubber is 

damaged, separated, or partially missing replace torsional damper, refer to 4.9.1.b. 

 (2) Grasp outer ring of torsional damper and attempt to turn torsional damper in both directions. If 

rotation is felt replace torsional damper, refer to step 4.9.1.b. 

 (3) Check torsional damper radial runout as follows: 

 (a) Run engine until engine is at operating temperature, refer to TM 9-6115-672-14. 

 (b) Attach magnetic base of dial indicator to magnetic surface near torsional damper. 

 (c) Position dial indicator against outer diameter of torsional damper and zero dial indicator. 

 (d) Rotate engine 360 ° (1 complete revolution) using flywheel rotation tool while observing 

dial indicator. If runout exceeds 0.060 in. (1.50 mm) replace torsional damper, refer to 

step b. 

 (4) Check torsional damper wobble as follows: 

 (a) Attach magnetic base of dial indicator to magnetic surface near torsional damper. 

 (b) Position dial indicator against side of outer ring of torsional damper and zero dial 

indicator. 

 (c) Rotate engine 360 ° (1 complete revolution) using flywheel rotation tool while observing 

dial indicator. If wobble exceeds 0.060 in. (1.50 mm) replace torsional damper, refer to 

step b. 

 (d) Position dial indicator against side of inner ring of torsional damper and zero dial 

indicator. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-91 

 (e) Rotate engine 360 ° (1 complete revolution) using flywheel rotation tool while observing 

dial indicator. If wobble exceeds 0.020 in. (0.5 mm) replace torsional damper, refer to 

step b. 

b. Removal.

 (1) Remove fan drive belt and fan, refer to TM 9-6115-672-14. 

CAUTION

Torsional damper is sensitive to impact damage. Do not drop or hammer 

on damper. 

 (2) Remove bolts (3, Figure 4-60). 

FIGURE 4-60. CRANKSHAFT PULLEY 

 (3) Grasp torsional damper (2, Figure 4-60) and remove from crankshaft. 

c. Replacement.

 (1) Inspect torsional damper, refer to 4.8.1.a. Replace if damaged. 

 (2) Remove torsional damper, refer to 4.8.1.b. 

 (3) For installation, refer to 4.8.1.d. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-92 

d. Installation.

 (1) Apply loctite to bolts (3, Figure 4-60). 

CAUTION

Install SAE Grade 8 or higher bolts in torsional damper. Failure to comply 

could result in engine damage. 

 (2) Position torsional damper (2) on crankshaft and install bolts (3). Torque bolts to 44 lb-ft (60 Nm). 

 (3) Re-torque bolts (3) to 59 lb-ft (80 Nm). 

 (4) Install fan and fan drive belt, refer to TM 9-6115-672-14. 

4.9.2. CRANKSHAFT PULLEY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

 (1) Remove torsional damper, refer to paragraph 4.9.1. 

 (2) Remove crankshaft pulley (1, Figure 4-60). 

b. Inspection.

 (1) Remove crankshaft pulley (1), refer to 4.9.2.a. 

 (2) Inspect crankshaft pulley (1) for cracks and wear. Replace as necessary. 

 (3) Install crankshaft pulley (1), refer to 4.9.2.d. 

c. Replacement.

 (1) Remove crankshaft pulley, refer to 4.9.2.a. 

 (2) Inspect crankshaft pulley (1, Figure 4-60) and pulley key, refer to 4.9.2.b. Replace if defective. 

 (3) Install crankshaft pulley (1), refer to 4.9.2.d. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-93 

d. Installation.

 (1) Position crankshaft pulley (1, Figure 4-60) on crankshaft. 

 (2) Install torsional damper, refer to paragraph 4.9.1. 

4.9.3. TIMING GEAR COVER.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

 (1) Drain lubrication system, refer to TM 9-6115-672-14. 

 (2) Remove fan drive belt and fan, refer to TM 9-6115-672-14. 

 (3) Remove alternator and alternator mounting bracket, refer to paragraph 3.9.1. 

 (4) Remove water pump if needed, refer to paragraph 3.8.3. 

 (5) Remove fan pulley and fan drive assembly as follows; 

 (a) Remove bolts (1, Figure 4-61) and fan pulley (2). 

 FIGURE 4-61. FAN DRIVE ASSEMBLY 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-94 

 (b) Mark bolt positions (B) on timing gear cover before removal to assure that fan pulley is 

installed in same position as removed and assure proper belt tension. 

 (6) Remove hub and fan drive assembly (3). 

 (7) Remove torsional damper, refer to paragraph 4.9.1. 

 (8) Remove crankshaft pulley, refer to paragraph 4.9.2. 

 (9) Remove water pump tube from water pump cover, refer to paragraph 3.8.2. 

 (10) Remove oil pan, refer to paragraph 4.5.3. 

 (11) Remove oil pressure regulating valve plug, refer to paragraph 4.5.2. 

 (12) Remove bolts (5, 6, 10, and 17, Figure 4-62), stud nuts (16), timing gear cover, and gasket. 

Discard gasket. 

 (13) Cover all openings to prevent entry of foreign material. 

b. Inspection.

 (1) Remove timing gear cover, refer to 4.9.3.a. 

 (2) Remove oil seal (11, Figure 4-62). 

__________

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

 Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

 (3) Thoroughly clean timing gear cover in solvent. Dry with compressed air. 

 (4) Inspect timing gear cover for cracks or other damage. Replace as required. 

 (5) Inspect front crankshaft oil seal bore for nicks. Repair or replace as required. 

 (6) Install timing gear cover, refer to 4.9.3.d. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-95 

FIGURE 4-62 TIMING GEAR COVER 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-96 

c. Replacement.

 (1) Remove timing gear cover, refer to 4.9.3.a. 

 (2) Inspect timing gear cover, refer to 4.9.3.b. Replace if damaged. 

 (3) For installation, refer to 4.9.3.d. 

d. Installation.

 (1) Remove all covering installed during 4.9.3.a (13). 

 (2) Insure all gasket material is removed from sealing surfaces. 

 (3) Position gasket (1, Figure 4-62) and timing gear cover (2) on front plate and install bolts (5, 6, 10, 

and 17) and stud nuts (16). Torque bolts and stud nuts to 26 lb-ft (35 Nm). 

 (4) Install oil pressure regulating valve assembly, refer to paragraph 4.5.2. 

 (5) Install adjustable fan drive assembly and fan pulley, as follows; 

 (a) Install fan pulley (2, Figure 4-61). Install bolts (1). Ensure bolts are installed in positions 

as marked in paragraph 4.9.3 (a) step 5. to assure proper belt tension. 

 (b) Install belt, refer to TM 9-6115-672-14. 

(6) Install water pump, if removed, refer to paragraph 3.8.3. 

 (7) Install water pump tube to water manifold cover, refer to paragraph 3.8.2. 

 (8) Install oil pan, refer to paragraph 4.5.3. 

 (9) Install crankshaft front wear sleeve as follows: 

 (a) Coat inner diameter of new wear sleeve with Retaining Compound. 

 (b) Position wear sleeve on nose of crankshaft with flange of crankshaft front wear sleeve 

toward crankshaft. 

 (c) Position installation tool over crankshaft front wear sleeve. Install crankshaft front wear 

sleeve until tool bottoms against nose of crankshaft, using a dead blow hammer. 

 (d) Clean any sealant from outer diameter of crankshaft flange and wear sleeve. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-97 

 (10) Install crankshaft front oil seal as follows: 

 (a) Inspect and clean seal bore in timing gear cover. Check for nicks or burrs. Use medium 

grit emery cloth to smooth rough areas. 

 (b) Clean outer diameter of crankshaft and wear sleeve with solvent (Appendix E) or ignition 

cleaner and allow to dry. 

 (c) Slide Adapter on nose of crankshaft and install bolts. 

CAUTION

Do not allow oil to contact coating on outer diameter of crankshaft front oil 

seal. Failure to comply could result in damage to crankshaft front oil seal 

and oil leakage. 

NOTE 

Position spring loaded side of crankshaft front oil seal into timing gear 

cover first. 

 (d) Apply light coat of clean engine oil to flange of crankshaft front oil seal and position 

crankshaft front oil seal on crankshaft flange. 

 (e) Place installer over adapter. Tighten screw until driver bottoms against nose on 

crankshaft. 

 (11) Install crankshaft pulley, refer to paragraph 4.9.2. 

 (12) Install torsional damper, refer to paragraph 4.9.1. 

 (13) Install alternator mounting bracket and alternator, refer to paragraph 3.9.1. 

 (14) Install fan and fan drive belt, refer to TM 9-6115-672-14. 

 (15) Service lubrication system, refer to TM 9-6115-672-14. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-98 

4.10. VEHICLE ENGINE STAND

NOTE 

The 2000 lb (908 kg) Vehicle Engine Stand (NSN 4910-01-016-1835) is 

referenced in this manual. When any other repair stand is used, consult the 

manufacturer's instructions for mounting the engine. 

__________

WARNING

The vehicle engine stand should be used only by qualified service 

technicians familiar with this equipment. Failure to comply could result in 

personal injury and/or equipment damage. 

__________

WARNING

Use alloy steel SAE Grade 8 or higher socket head cap screws when 

installing engine adapters on vehicle engine stand. Use Thread Lock and 

Sealer (Loctite 242) or equivalent on cap screws when installing lift straps 

on the engine. Tighten cap screws to 125 lb-ft (170 Nm). Failure to comply 

could result in personal and/or equipment damage. 

__________

WARNING

Be sure that tapped hole on the vehicle repair stand's adapter and 

mounting hub are clean and not damaged. Ensure that thread engagement 

is within 1-1.2 times the screw diameter minimum to properly secure the 

engine. Failure to comply could result in personal injury and/or equipment 

damage. 

__________

WARNING

To avoid structural or personal injury, do not exceed the maximum 

capacity rating or 2000 lbs. (908 kg.). Maximum capacity is determined 

with the center of the engine located no more than 13 inches (330 mm) from 

the mounting hub surface of the engine stand. 

__________

WARNING

Be sure that the center of the engine must be located within 2 inches (51 

mm) of the engine stand rotating shaft to prevent unsafe off-balance load 

condition. Failure to comply could result in personal injury and/or 

equipment damage. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24 

4-99 

__________

WARNING

Recheck to make sure engine is solidly mounted before releasing support 

from engine lifting device. Failure to comply could result in personal injury 

and/or equipment damage. 

__________

WARNING

Never permit any part of the body to be positioned under a load being lifted 

or suspended. Failure to comply could result in personal injury. 

__________

WARNING

The lifting jack is to be used when it is necessary to lift the engine for 

rotation. When working on the engine, the jack should be at its lowest 

position to keep the center of gravity low and the possibility of tipping low. 

__________

WARNING

Unscrew the release valve slowly when lowering the engine on vehicle 

engine stand to prevent sudden engine movement. Do not unscrew release 

valve knob more than two turns from its closed position. Failure to comply 

could result in personal injury and/or equipment damage. 

CAUTION

Use extreme caution when lifting and NEVER permit any part of the body 

to be positioned under an engine being lifted or suspended. 

CAUTION

Lift engine with longitudinal loading on lift sling and lifting brackets only. 

Angular loading greatly reduces lifting capacity of sling and brackets. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-100 

 a. Lift engine using the following steps; 

 (1) Attach Engine Lifting Sling to engine lifting straps and overhead hoist on floor crane. 

NOTE 

Use of an engine lifting sling as shown in Figure 4-63 is the only 

APPROVED method of lifting an engine. 

 

FIGURE 4-63. ENGINE LIFTING 

 (2) Carefully lift engine to desired location. 

 

CAUTION

When servicing turbocharged engines on a rollover stand, disconnect 

turbocharger oil inlet line from the oil filter housing or turbocharger before 

rolling engine over. Failure to do so may cause a hydraulic lock upon 

starting engine. Hydraulic lock may cause possible engine failure. 

NOTE 

Hydraulic lock is the event that occurs when trapped oil in the oil filter 

housing drains through the turbocharger, to the exhaust and intake 

manifolds, and into the cylinder head. After starting the engine, the 

trapped oil in the manifold and head is released into the cylinder(s) filling 

them with oil causing hydraulic lock and possible engine failure. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

4-101/4-102 BLANK 

 b. Disconnect turbocharger oil inlet line as follows; 

 (1) Drain all engine oil and coolant, if not previously done. 

 (2) Disconnect turbocharger oil inlet line, refer to paragraph 4.4.1. 

CAUTION

NEVER remove the overhead lifting equipment until the engine is secure 

mounted onto the repair stand and all mounting hardware is tightened to 

specific torque. Always release the overhead lifting equipment slowly. 

 c. Mount engine on vehicle engine stand using the following steps; 

 

 (1) If not done previously, remove turbocharger. Refer to paragraph 4.4.1. Ensure oil and 

coolant are drained as stated in 4.10.b. above. 

 (2) Mount engine on vehicle engine stand. 

ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-1 

CHAPTER 5 

 GENERAL SUPPORT MAINTENANCE INSTRUCTIONS 

 Section I. TROUBLESHOOTING 

5.1. GENERAL SUPPORT TROUBLESHOOTING PROCEDURES.

This section does not contain any troubleshooting information for locating and correcting operating engine troubles 

at the general support level. General support is limited to the disassembly, cleaning, inspection and assembly of 

components after troubleshooting has already been accomplished. Refer to Table 5-1 for maintenance procedures 

covered in this chapter. For troubleshooting, refer to Table 3-1 for troubleshooting at the unit level and Table 4-1 

for troubleshooting at the direct support level. 

NOTE 

Before using troubleshooting Tables 3-1 and 4-1, be sure you have 

performed your PMCS. Prior to performing troubleshooting procedures 

within this manual, perform previous maintenance level troubleshooting 

procedures and TM 9-6115-672-14 troubleshooting procedures. 

Table 5-1. Procedural Index for General Support Maintenance 

Subject Paragraph 

Fuel Injection Pump.....................................................................................................................................5.3.1. 

Camshaft Assembly ....................................................................................................................................5.4.1. 

Idler Gears and Idler Gear Shafts ...............................................................................................................5.4.2. 

Front Plate ..................................................................................................................................................5.4.3. 

Crankshaft and Main Bearings ....................................................................................................................5.4.4. 

Pistons and Connecting Rods ......................................................................................................................5.4.5. 

Cylinder Liners ...........................................................................................................................................5.4.6. 

Cylinder Block ............................................................................................................................................5.4.7. 

Oil Pump Assembly.....................................................................................................................................5.4.8 

Oil Bypass Valve Assembly ........................................................................................................................5.4.9 

Cylinder Head..............................................................................................................................................5.4.10 

Oil Pressure Regulating Valve Assembly Valve Seat..................................................................................5.4.11 

Fuel Injection Pump.....................................................................................................................................5.4.12 

Section II. MAINTENANCE PROCEDURES 

5.2. GENERAL.

This section contains general support maintenance procedures. Topics covered at this level include disassembly, 

cleaning, inspection and assembly of components. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-2 

5.3. FUEL SYSTEM MAINTENANCE

5.3.1. FUEL INJECTION PUMP.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

NOTE 

If working on fuel injection pump on TQG, refer to TM 9-6115-672-14 for 

removal and installation procedure for electrical actuator. 

a. Test.

NOTE 

Test bench coupling should be of self aligning, zero backlash type. 

(1) Remove injection pump, refer to paragraph 4.6.1.a. 

(2) Install injection pump on a motorized test bench meeting ISO Standard 4008. 

(3) Ensure rotation of drive shaft on test stand is clockwise. 

CAUTION

If incorrect connector is used on the transfer pump inlet, damage to 

internal threads will occur. 

(4) Install transfer pump inlet connector from the transfer pressure adjusting tool kit. 

(5) Install transfer pressure gage connector. 

(6) Install a shutoff valve to isolate gage when not in use. 

(7) Remove timing line cover and install advanced indicator. 

(8) Energize electric shutoff device with 24 VDC at lowest speed. 

(9) Move pump throttle lever to full load position. 

(10) Pressurize transfer pump inlet to 5.0 ± 0.5 psi (34 ± 3 kPa). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-3 

NOTE 

When transfer pump is primed, allow fuel to bleed for several seconds from 

loosened injection line nuts at nozzles. 

(11) With pump operating at 300 rpm, bleed injector lines. 

(12) After bleeding, tighten nuts securely. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Pressure will not exceed 30 psig (207 kPa). Eye protection 

required. 

CAUTION

Under no circumstances should 130 psi (896.4 kPa) transfer pump pressure 

be exceeded, to prevent damage to the pump. 

NOTE 

Table 5-2 lists fuel delivery in cubic millimeters/stroke. Some test benches 

measure fuel flows in cubic centimeters (milliliters). To convert from 

mm3/stroke to CC's, use the following formula: 

CC's = (mm3/stroke x No. of strokes)/1000 

NOTE 

All rpm readings are at pump speed. 

(13) Operate pump at 1000 pump rpm wide open throttle (WOT) for ten minutes or until temperature 

reaches 110°F to 115°F (43.3°C to 46.1°C). Completely dry pump off using compressed air. 

Observe for leaks and correct as necessary. 

CAUTION

Never back out low idle screw or disengagement of throttle lever from guide 

bushing could result. 

(14) Back out high idle screw. 

(15) Close valve in fuel supply line. With pump running 400 pump rpm, the transfer pump must be 

capable of creating a vacuum of at least 18 inches (45.7 cm) of mercury. If it does not, check for 

air leaks between pump inlet and shutoff valve or deficiency in transfer pump. 

(16) Fill graduates to bleed air from test stand and to lubricate graduates. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-4 

(17) While operating pump at 1750 rpm wide open throttle (WOT), perform the following: 

NOTE 

Pressure should be 74 to 76 psi (510 to 524 kPa) 

(a) Observe transfer pump pressure. To adjust pressure, remove lines to transfer pump inlet 

connector and use a 5/32 inch hex key wrench to adjust pressure regulating spring plug. 

Clockwise adjustment increases pressure. Do not over-adjust. 

NOTE 

Transfer pump pressure gage must be isolated by shutoff valve at injection 

pump when checking fuel delivery and advance movement. 

NOTE 

Oil return flow reading should be 400 to 700 cc/min. 

(b) Check return oil flow. 

(c) Recheck transfer pump pressure. Adjust as necessary. 

(d) Check housing pressure for 8.5 to 13.5 psi (59-93 kPa). 

(18) While operating at 1750 rpm WOT, set advance trimmer screw for 0 degrees. 

(19) While operating at 1750 rpm WOT, set roller-to-roller fuel delivery to 104.5 to 105.5 mm3/stroke. 

(20) Turn speed droop adjusting cap clockwise six full turns. 

(21) While operating at 1750 rpm WOT, set light load advance adjusting screw for 5.0 degrees. 

(22) While operating at 300 rpm, with supply pump on unscrew advance cap four full turns and allow 

fuel to bleed for 30 seconds. Retorque cap to 455-505 lb-in (51 – 57 Nm). 

(23) Adjust speed droop to minimum droop position counterclockwise. Turn speed droop cap in two 

full turns clockwise. 

(24) While operating at 2290 rpm WOT, adjust high idle screw to obtain maximum 5 mm3/stroke. 

(25) Perform the checks at pump rpm specified in Table 5-2. 

(26) Install injection pump, refer to paragraph 4.6.1.d. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-5 

Table 5-2. Fuel Injection Pump Checks

NOTE 

Throttle position is at full load, wide open position (WOT).

 PUMP RPM THROTTLE 

POSITION 

 mm3

/STROKE ADVANCE PRESS 

 150 

 400 

 1750 

 1750 

 1750 

 2290 

 WOT 

 WOT ♦

 WOT 

 ADJ 

 WOT ♦

 WOT 

 42 Min. 

 4 Max. 

 104.5-105.5 

 26-34 

 4 Max. 

 5 Max. 

 ----- 

 ----- 

 0° 

 4.5°- 5.5° 

 ----- 

 8.0°- 9.0° 

♦♦10 Min. 

----- 

♦♦♦74-76 

----- 

----- 

----- 

 Legend: ♦ Electric Shut Off (ESO) Deenergized 

 ♦♦ (69 kPa) 

 ♦♦♦ (614-628 kPa) 

NOTE 

A generic (DB Series) fuel injection pump is illustrated Figures 5-1 thru 5-

16. 

b. Disassembly.

(1) Remove fuel injection pump, refer to paragraph 4.6.1. 

(2) Remove governor actuator from top of fuel injection pump (1, Figure 5-1), refer to TM 9-6115-

672-14. 

(3) Remove flange seal (2, Figure 5-1) and discard. 

(4) Clamp pump holding fixture in vise and mount fuel injection pump on pump holding fixture. 

Refer to Appendix F, Figure F1. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-6 

FIGURE 5-1. FUEL INJECTION PUMP (PAGE 1 OF 3) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-7 

FIGURE 5-1. FUEL INJECTION PUMP (PAGE 2 OF 3) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-8 

LEGEND 

1 HOUSING ASSY 36 PLUG, PISTON HOLE 71 LIP SEAL, D.S., FUEL SIDE 

2 SEAL, FLANGE 37 SEAL, O-RING 72 CAP, TRANSFER PUMP END 

3 CLIP, HOOK 38 PISTON, ADVANCE 73 FILTER, INLET 

4 SHAFT ASSY, THROTTLE 39 SCREW, REED VALVE 74 REGULATOR ASSY, TRANSFER PUMP 

5 LEVER, THROTTLE FORK 40 VALVE, REED 75 SCREW, ADJUSTING 

6 SEAL, O-RING 41 RING, ADVANCE PISTON 76 SPRING, REGULATING 

7 WASHER, SPACER 42 SEAL, PISTON RING 77 PISTON, REGULATOR 

8 SPACER 43 ARM ASSY, METERING VALVE 78 SEAL, REGULATOR SLEEVE 

9 BARREL ASSY, DAMPER 44 SPRING, METERING VALVE 79 ROLLPIN, REGULATOR ASSY 

10 PISTON ASSY, DAMPER 45 SHIM, METERING VALVE SPRING 80 LINER, TRANSFER PUMP 

11 SPRING, DAMPER 46 VALVE, METERING 81 BLADE, TRANSFER PUMP 

12 CAP, CONTROL LOCKING 47 SCREW ASSY, VENT 82 SPRING, TRANSFER PUMP BLADE 

13 CAP ASSY, ADJUSTING 48 HEAD ASSY, HYDRAULIC 83 RING, LINER LOCATING 

14 SEAL, O-RING 49 SLEEVE, THRUST 84 RETAINER, ROTOR 

15 PIN, CONTROL SPRING 50 WASHER, THRUST 85 SEAL, O-RING 

16 GUIDE, CONTROL ROD 51 WEIGHT, GOVERNOR 86 ROTOR ASSY 

17 WASHER, SEALING 52 NUT, PIVOT SHAFT 87 SEAL, O-RING 

18 SPRING, GOVERNOR CONTROL 53 SEAL, O-RING 88 CAM RING 

19 ROD ASSY, CONTROL 54 SHAFT, PIVOT 89 SCREW, LEAF SPRING 

20 SCREW, LOCKING PLATE 55 ARM, GOVERNOR 90 SPRING, LEAF 

21 PLATE, LOCKING 56 HOOK, GOVERNOR LINKAGE 91 ROLLER, CAM 

22 SEAL, O-RING 57 SPRING, GOVERNOR LINKAGE 92 SHOE, CAM ROLLER 

23 SCREW, HEAD LOCKING 58 RING, RETAINING 93 PLUNGER, LONG 

24 SCREW, HEAD LOCATING 59 WASHER, SPRING 94 PLUNGER, SHORT 

25 SEAL, O-RING 60 WASHER, THRUST 95 SCREW, RETAINING 

26 PLUG, ADVANCE SCREW HOLE 61 BEARING, THRUST 96 STOP, DELIVERY VALVE 

27 SEAL, O-RING 62 DRIVE SHAFT 97 SPRING, DELIVERY VALVE 

28 PLUG, PISTON HOLE 63 NUT, DRIVE SHAFT 98 VALVE, DELIVERY 

29 SEAL, O-RING 64 LOCKWASHER, DRIVE SHAFT 99 CLIP, RETAINING 

30 SPRING, ADVANCE 65 KEY, WOODRUFF 100 RETAINER, CUSHION 

31 GUIDE, ADVANCE ADJ SPRING 66 SCREW, LOCK 101 RETAINER, WEIGHT 

32 NUT, LOCK 67 SEAL, O-RING 102 CUSHION, WEIGHT RETAINER 

33 SCREW, TRIMMER 68 BEARING, NEEDLE 103 SCREW, NAMEPLATE 

34 SEAL, O-RING 69 LIP SEAL, D.S., LUBE OIL SIDE 104 NAMEPLATE 

35 PIN, CAM ADVANCE 70 SPACER, LIP SEAL 

FIGURE 5-1. FUEL INJECTION PUMP (PAGE 3 OF 3) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-9 

(5) Disconnect hook clip (Figure 5-2). 

FIGURE 5-2. CLIP REMOVAL. 

(6) Remove throttle shaft assembly (4), throttle lever fork (5), O-ring seal (6) spacer washer (7), and 

spacer (8). Discard O-ring seal and spacer washer. 

(7) Remove damper barrel (9), damper piston (10), and damper spring (11). 

(8) Remove droop control locking cap (12) using one wrench to hold control rod guide (16) while 

another wrench is used to loosen droop control locking cap, refer to Figure 5-3. 

FIGURE 5-3. DROOP CONTROL LOCKING CAP REMOVAL. 

CLIP 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-10 

(9) Remove adjusting cap assembly (13, Figure 5-1) by twisting and pulling. Remove O-ring seal 

(14) and spring pin (15). Discard O-ring seal. 

(10) Remove control rod guide (16) and seal washer (17). Discard seal washer. 

(11) Disengage governor spring (18) from governor arm (55), refer to Figure 5-4. Depress metering 

valve arm (43) and remove control rod assembly (19) and governor spring. 

FIGURE 5-4. CONTROL ROD ASSEMBLY AND GOVERNOR SPRING REMOVAL. 

(12) Remove screw (20), locking plate (21), and O-ring seal (22). Discard O-ring seal. 

(13) Loosen but do not remove transfer pump end cap (72) using wrench. 

(14) Remove head locking screws (23). 

(15) Invert fuel injection pump housing (1) in vise and remove head locating screw (24) and O-ring 

seal (25). Discard O-ring seal. 

(16) Remove cam advance pin hole plug (26) and O-ring seal (27). 

(17) Loosen locknut (32). Remove spring side piston hole plug (28) using wrench. 

(18) Remove O-ring seal (29), spring (30), spring seat (31), locknut (32), trimmer screw (33), and Oring seal (34). Discard O-ring seals. 

(19) Remove cam advance pin (35) using needle nose pliers, refer to Figure 5-5. 

(20) Remove power side piston hole plug (36), O-ring seal (37), and advance piston (38). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-11 

(21) Remove screws (39) and reed valve (40) from power side piston hole plug (36), refer to 

Figure 5-6. 

FIGURE 5-5. CAM ADVANCE PIN REMOVAL. 

FIGURE 5-6. REED VALVE REMOVAL. 

CAUTION

Piston ring is fragile and easily damaged. Do not over expand piston ring 

during removal. Failure to comply could result in damage to piston ring. 

(22) Remove piston ring (41, Figure 5-1) using snap ring pliers (13337). Remove and discard seal 

(42). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-12 

(23) Invert fuel injection pump in vise. Rotate hydraulic head assembly (48) counterclockwise in fuel 

injection pump housing (1) and lift linkage hook (56) off metering valve arm (43). Disconnect 

linkage hook from governor arm (55) and hang linkage hook over side of fuel injection pump 

housing, refer to Figure 5-7. 

FIGURE 5-7. LINKAGE HOOK DISCONNECTION. 

(24) Remove metering valve arm (43), spring (44), shim (45), and metering valve (46). 

(25) Remove vent screw assembly (47). 

(26) Remove hydraulic head assembly (48) by tilting fuel injection pump housing (1) downward and 

twisting and pulling on hydraulic head assembly, refer to Figure 5-8. 

FIGURE 5-8. HYDRAULIC HEAD ASSEMBLY REMOVAL. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-13 

(27) Remove thrust sleeve (49, Figure 5-1), thrust washer (50), and governor weights (51). 

(28) Remove pivot shaft nut (52) and O-ring seal (53) from one side of pivot shaft (54). 

(29) Remove pivot shaft (54), governor arm (55), and linkage hook (56), refer to Figure 5-9. 

FIGURE 5-9. GOVERNOR ARM AND LINKAGE HOOK REMOVAL 

(30) Remove retaining ring (58, Figure 5-1) using snap ring pliers (20044). Remove thrust spring (59) 

and thrust washer (60). Remove thrust bearing (61) using snap ring pliers (20043). 

CAUTION

Drive shaft is easily damaged. Handle drive shaft with care. Failure to 

comply could result in damage to fuel injection pump. 

(31) Remove drive shaft (62), drive shaft nut (63), lock washer (64), and Woodruff key (65). 

(32) Remove screw (66) and gasket (67). Discard gasket. 

(33) Position fuel injection pump housing (1) with flange facing upwards. Remove drive shaft bearing 

(68), oil side seal (69), spacer (70) and fuel side seal (71) using Bearing and Seal Puller (28311), 

refer to Figure 5-10. Discard drive shaft bearing, oil side seal, and fuel side seal. 

(34) Remove transfer pump end cap (72, Figure 5-1), inlet filter screen (73), and transfer pump 

regulator assembly (74). 

(35) Remove adjusting screw (75), regulating spring (76), regulator piston (77), sleeve seal (78), and 

regulator assembly roll pin (79). Discard sleeve seal. 

(36) Remove transfer pump liner (80), transfer pump blades (81), and transfer pump blade springs (82). 

(37) Remove liner locating ring (83) and rotor retainers (84). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-14 

FIGURE 5-10. DRIVE SHAFT BEARING AND SEAL REMOVAL (SHOWN REMOVED). 

 (38) Remove transfer pump end cap seal (85), refer to Figure 5-11. 

FIGURE 5-11. TRANSFER PUMP END CAP SEAL REMOVAL 

(39) Remove rotor assembly (86, Figure 5-1). 

(40) Remove and discard O-ring seal (87). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-15 

NOTE 

Note direction (clockwise or counterclockwise) of directional arrow to 

insure proper installation. 

(41) Remove cam ring (88), refer to Figure 5-12. 

FIGURE 5-12. CAM RING REMOVAL. 

(42) Remove adjusting screws (89, Figure 5-1), leaf springs (90), cam rollers (91), and cam roller shoes 

(92). 

NOTE 

Note location of short and long pumping plungers to insure proper 

installation. 

(43) Remove long pumping plungers (93) and short pumping plungers (94) using Brass Hook (13301), 

refer to Figure 5-13. 

FIGURE 5-13. PUMPING PLUNGER REMOVAL. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-16 

(44) Position rotor (86, Figure 5-1) in (16313) fixture and clamp in vise. Remove retaining screw (95), 

delivery valve stop (96), and spring (97). Discard delivery valve stop. 

(45) Remove delivery valve (98) using delivery valve extractor (26081), refer to Figure 5-14. 

FIGURE 5-14. DELIVERY VALVE REMOVAL. 

(46) Remove retaining clips (99, Figure 5-1) by prying with small screwdriver, refer to Figure 5-15. 

Discard retaining clips. 

FIGURE 5-15. RETAINING CLIP REMOVAL. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-17 

(47) Remove retainer cushions (100, Figure 5-1), weight retainer (101), and weight retainer cushions 

(102). 

(48) If necessary, remove screws (103) and nameplate (104). 

(49) Remove and discard all seals. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Good general ventilation is normally adequate. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure must not exceed 30 psig (207 kPa). Eye protection 

required. 

(50) Thoroughly clean all parts in solvent. Dry all parts with compressed air. Dip all parts in clean 

calibrating fluid. 

c. Repair.

(1) Disassemble fuel injection pump, refer to paragraph 5.3.1.a. 

(2) Inspect each component for excessive wear, scoring, corrosion, distortion, cracks, or breakage. 

Replace all damaged or excessively worn parts. 

(3) Inspect fuel injection housing (Figure 5-16) as follows: 

FIGURE 5-16. FUEL INJECTION HOUSING. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-18 

(a) Inspect fuel injection housing for cracks or signs of damage. 

(b) Inspect threaded holes for damage. 

(c) Inspect inside of fuel injection housing where hydraulic head seal contacts fuel injection 

pump. Inspect thrust bearing counterbore and area where cam ring rides. 

(d) Replace fuel injection housing as required. 

CAUTION

Drive shaft is fragile and easily damaged. Handle drive shaft with care. 

(4) Inspect drive shaft (1, Figure 5-17) as follows: 

FIGURE 5-17. DRIVE SHAFT. 

NOTE 

Drive shaft seal wear bands are normal and should not be reason for drive 

shaft replacement. 

(a) Inspect threads (2, Figure 5-17) and taper (3) for damage. 

(b) Inspect drive shaft (1) where drive shaft seals ride for nicks or scratches. 

(c) Measure drive shaft tang (5) width using outside diameter micrometer. Drive shaft tang 

width should be 0.430 in. (10.92 mm) minimum. If drive shaft tang width is less than 

specifications, replace drive shaft. 

(d) Replace drive shaft as required. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-19 

(5) Inspect cam ring (1, Figure 5-18). Carefully inspect cam lobes and edges of all flat surfaces. If 

there is evidence of spalling or flaking out, replace with a new cam. 

NOTE 

Only working portions of lobes on inside diameter are ground, so any tool 

marks between lobes should not be considered as damage. The mottled 

appearance of cam is from heat treatment rather than from operation. 

FIGURE 5-18. CAM RING. 

(6) Examine the Hydraulic Head Assembly. Refer to Figure 5-19. 

(a) Examine the metering valve bore and the threaded holes for damage. 

(b) Examine the rotor bore for wear band in line with the charging ports and/or the discharge 

ports which could indicate that dirty fuel was used. 

(c) Inspect the discharge fittings for damage to the area where the injection lines seat or to 

the threads. 

(d) Check the threaded hydraulic head plugs to ensure they are tight. 

(e) Replace the Hydraulic Head Assembly if found defective. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-20 

FIGURE 5-19. HYDRAULIC HEAD ASSEMBLY (TYPICAL) 

(7) Examine the Distributor Rotor Assembly. Refer to Figure 5-20. 

(a) Examine the working areas of the distributor rotor including the transfer pump blade 

slots, the discharge and charging ports, the plunger bores, the leaf spring contact area and 

the drive slot. Check for wear, erosion or damage. 

(b) Examine the flat delivery valve seat in the rotor bore for chipping, erosion or damage. 

 

(c) Ensure the governor weight retainer is secure on the rotor. If hub is loose, head and rotor 

assembly must be replaced. 

(d) Replace the Distribution Rotor Assembly if found defective. 

FIGURE 5-20. DISTRIBUTOR ROTOR ASSEMBLY (TYPICAL) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-21 

(8) Examine the Shoes and Rollers. Refer to Figure 5-21. 

(a) Inspect the edge of the shoe that has been in contact with the leaf spring for excessive 

wear or damage. Shoes with sides of equal height may be reversed in the shoe slot to 

expose the unused surface to the leaf spring. 

(b) Inspect the inside of the shoe where the roller rides and the outside diameter of the roller 

for scoring. 

(c) Ensure the rollers are a close fit in the shoes. 

(d) Replace the Shoes and Rollers if found defective. 

FIGURE 5-21. SAMPLE SHOES AND ROLLERS. 

(9) Examine the Leaf Springs. Refer to Figure 5-22. 

(a) Examine the surface of the leaf spring which contacts the cam roller shoes. 

(b) Inspect the area on the underside of the leaf spring which contacts the rotor. Replace the 

leaf spring if there is evidence of pitting or excessive fretting. 

(c) Replace the Leaf Springs if found defective. 

FIGURE 5-22. LEAF SPRINGS. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-22 

(10) Examine the Transfer Pump Blades. Refer to Figure 5-23. 

(a) Inspect for excessive wear and scoring of the edge of the blade which rides on the inside 

of the transfer pump liner. A minimum allowable thickness is provided in Figure 5-23. 

(b) Examine the sides of the blades for wear from contact with the blade slots. 

(c) Replace the Transfer Pump Blades if found defective. 

FIGURE 5-23. TRANSFER PUMP BLADES. 

(11) Examine the Transfer Pump Liner. Refer to Figure 5-24. 

(a) Examine the inside diameter of the liner for scoring or excessive wear. 

(b) Replace Transfer Pump Liner if scored or wear is excessive. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-23 

FIGURE 5-24. TRANSFER PUMP LINER. 

(12) Examine the Transfer Pump Regulating Piston and Adjusting Screw. refer to Figure 5-25. 

(a) Inspect the adjusting screw to ensure the orifice is not plugged and the orifice plate is 

secure to the screw. 

(b) Replace the screw if the retention patch does not offer enough resistance to turning when 

the screw is threaded in and out of the regulator. 

(c) Inspect the regulating piston. Replace if excessive scoring or wear is present. 

(d) Replace the Transfer Pump Regulating Piston and Adjusting Screw if found defective. 

FIGURE 5-25. TRANSFER PUMP REGULATING PISTON AND ADJUSTING SCREW. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-24 

(13) Examine the Transfer Pump Regulator Assembly. Refer to Figure 5-26. 

(a) Examine the face of the regulator where the transfer pump blades ride. The face may be 

lapped with fine grit lapping compound if light wear is present. 

(b) Examine the regulating piston bore and transfer pressure regulating slot for wear or 

damage. Replace the regulator locating pin if bent or broken. 

(c) Replace the Transfer Pump Regulator Assembly if found defective. 

FIGURE 5-26. TRANSFER PUMP REGULATOR ASSEMBLY. 

(14) Examine the Metering Valve and Arm Assembly. Refer to Figure 5-27. 

(a) Inspect the metering valve arm to be sure the pin on which the linkage hook rides is 

tightly mounted to the arm. 

NOTE 

The appearance of the valve is not the best criteria for determining if a 

valve should require replacement. The pump's ability to pass the test 

specifications, along with shut-off requirements should be the best guide as 

to whether the valve is replaced or not. 

(b) Check the valve to ensure it is securely attached to the arm. Examine the valve for 

excessive scoring. 

(c) Replace the Metering Valve and Arm Assembly if found defective. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-25 

FIGURE 5-27. METERING VALVE AND ARM ASSEMBLY. 

(15) Examine the Delivery Valve. Refer to Figure 5-28. 

(a) Inspect the cuff of the delivery valve for excessive scratching or scoring. 

(b) Examine for a wear band around the center of the valve, which if excessive, is criteria for 

replacement of the valve. 

(c) Check the valve for correct retraction value 0.59 in. (15mm). 

(d) Replace the Delivery Valve if found defective. 

FIGURE 5-28. DELIVERY VALVE. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-26 

d. Assembly.

(1) Install nameplate (104, Figure 5-1) and screws (103). 

(2) Position fuel injection pump housing (1), flange facing up, on arbor press. Ensure fuel injection 

pump housing is resting flatly. 

CAUTION

Lubricants can cause damage to fuel side seal. Do not use any lubricants on 

fuel side seal when installing. Failure to comply could result in damage to 

fuel side seal. 

(3) Position fuel side seal (Figure 5-29) into fuel injection pump housing (1, Figure 5-1) bore with 

seal lip facing downwards. Position seal installation tool into fuel injection pump housing bore. 

Press fuel side seal in using arbor press until seal installation tool bottoms. 

FIGURE 5-29. FUEL SIDE SEAL INSTALLATION 

(4) Install spacer (70, Figure 5-1). 

(5) Apply light coating of Lubriplate grease to seal bore inside fuel injection pump housing (1). 

Install oil side seal (Figure 5-30) in fuel injection pump housing with seal lip facing outward using 

installation tool and arbor press. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-27 

FIGURE 5-30. OIL SIDE SEAL INSTALLATION 

(6) Install drive shaft bearing (Figure 5-31) with part number facing outward using installation tool 

and arbor press. Check drive shaft bearing rollers for freedom of movement. 

FIGURE 5-31. DRIVE SHAFT BEARING INSTALLATION 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-28 

(7) Position seal protection tube (included in seal and bearing kit) over drive shaft (Figure 5-32). 

Lubricate seal protection tube and drive shaft with clean calibrating fluid. 

FIGURE 5-32. SEAL PROTECTION TUBE 

(8) Insert seal protection tool and drive shaft (1, Figure 32) into fuel injection pump housing from 

flange end of fuel injection pump housing. Position shoulder of drive shaft flush with drive shaft 

bearing (1, Figure 5-31). Hold shoulder of drive shaft flush with face of drive shaft bearing and 

remove seal protection tube from inside of fuel injection pump housing. 

(9) Install thrust bearing (1, Figure 5-33) using snap ring pliers. Install thrust washer (2). 

FIGURE 5-33. THRUST BEARING AND THRUST WASHER 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-29 

(10) Install thrust spring (1, Figure 5-34) on top of thrust washer (2, Figure 5-33). Install retaining ring 

(2, Figure 5-34) using snap ring pliers (20044). 

FIGURE 5-34. SPRING WASHER AND RETAINING RING 

(11) Place new timing mark on hub as follows: 

(a) Place the rotor assembly onto the timing locator (20395) with drill point in rotor drive 

tang aligned with tool pointer. Refer to Figure 5-35. 

FIGURE 5-35. TIMING MARK LOCATOR 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-30 

(b) Rotate the pointer and rotor in the direction of rotation indicated on the pointer 

(counterclockwise) until pointer is aligned with specified number of degrees on upper or 

outer scale. Mark on hub should line up with zero on locator (where "place timing line 

here" arrow point is located). If line is not correct, use abrasive stone to remove incorrect 

mark from hub. Place a mark at the correct angle first using a pencil and then with 

electric marking pencil. 

(c) Timing mark is now in correct position. 

(12) Position rotor cushions (1, Figure 5-36) and cushion retainers (2) on weight retainer (3). 

(13) Install retaining clips (4). 

FIGURE 5-36. WEIGHT RETAINING ASSEMBLY. 

(14) Install delivery valve (98, Figure 5-1) using delivery valve extractor (26081). 

(15) Install spring (97), delivery valve stop (96), and screw (95) in rotor (86). Position rotor in fixture 

(16313) and secure fixture in vise. Torque screw (95) to 120 to 125 lb-ft (13.6 to 14.1 Nm). Refer 

to Figure 5-37. 

FIGURE 5-37. TIGHTENING DELIVERY VALVE STOP SCREW 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-31 

NOTE 

Orientation of pumping plungers is important. Ensure that long and short 

pumping plungers are installed in correct orientation. 

(16) Remove rotor (86, Figure 5-1) from fixture (16313). Install pumping plungers (Figure 5-38), refer 

to Figure 5-38 for correct orientation. 

FIGURE 5-38. PUMPING PLUNGER INSTALLATION. 

(17) Install cam roller shoes (1, Figure 5-39) and cam rollers (2) on rotor (3). 

(18) Install leaf springs (4) and adjusting screws (5). Bottom screws, then back out one full revolution. 

FIGURE 5-39. INSTALLING ROLLERS AND SHOES (TYPICAL) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-32 

(19) Measure the roller to roller dimension (Figure 5-40) by performing the following: 

(a) Secure roller-to-roller setting fixture (19969) in vise and insert rotor assembly. Connect 

dry, clean, filtered, compressed air source regulated to 40-100 psi. (4.5-11.3 kPa) to force 

plungers outward until shoes contact leaf spring. 

(b) Using a 1-2 inch micrometer, measure the distance between the outer surfaces of each 

pair of opposed rollers. Compare the dimensions to the roller-to-roller dimension called 

for on the individual specification, 1.966 in ± .0015 in (49.94 mm ± 0.04mm). Turn leaf 

spring adjusting screws clockwise to increase or counterclockwise to decrease the 

dimension. The two dimensions must be within 0.0003 inches (0.076 mm) of each other 

and the average of both roller-to-roller dimensions must be within 0.0015 of the specified 

dimension. 

Example: Specified roller-to-roller dimension = 1.966 inches (49.94 mm). One pair of rollers 

measures 1.967 inches (49.96 mm) while the other measures 1.964 inches (49.88 mm). 

The 2 dimensions are within .003 inches of each other and the average of the 2 

dimensions (1.9655 inches) is within 0.0005 inches of the specified roller-to-roller. Since 

each leaf spring controls one shoe and roller of each set it may be necessary to 

interchange shoes between slots, or install new shoes in each slot, in order to achieve the 

proper roller-to-roller dimension and concentricity. 

(c) After the roller-to-roller dimensions are achieved, the roller concentricity must be 

checked. Proper concentricity is needed to ensure that all rollers strike the cam lobes at 

the same time during pump operation. 

(d) Rotate the rotor until one roller is aligned with in dial indicator plunger on fixture 19969. 

Slide the indicator inward until plunger depresses at least 0.010 inches (0.254 mm). 

"Zero" indicator by loosening thumbscrew and rotating dial. Recheck "zero" by rotating 

rotor to be sure indicator plunger is on high point of cam roller. 

(e) Rotate rotor and observe dial indicator reading for each of the other rollers. Roller 

concentricity must be within 0.004 inches (0.1 mm). If not within specification, 

concentricity can be achieved through interchanging of shoes or leaf spring positions. 

FIGURE 5-40. MEASURING ROLLER TO ROLLER DIMENSION 
ARMY TM 9-2815-260-24 

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(20) Install seal (87, Figure 5-1) into groove on hydraulic head (48). 

(21) Position cam ring (88) on rotor assembly (86) with directional arrow facing counterclockwise 

when viewed from above. 

(22) Carefully slide hydraulic head assembly (87) over rotor. 

(23) Install transfer pump end cap seal (85). Ensure that transfer pump end cap seal is pushed 

completely down into groove. 

(24) Install rotor retainers (84). Align cutouts in rotor retainers with hole in hydraulic head. 

(25) Install liner locating ring (83) with opening in liner locating ring 90° (1/4 revolution) from rotor 

retainer (84) ends. 

(26) Install transfer pump liner (1, Figure 5-41) with notch aligned with hole in hydraulic head 

assembly (2). 

(27) Install transfer pump blades (Figure 5-42) and springs one pair at a time. 

FIGURE 5-41. TRANSFER PUMP LINER INSTALLATION (TYPICAL) 

FIGURE 5-42. TRANSFER PUMP BLADE INSTALLATION (TYPICAL). 
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(28) Install sleeve seal (78, Figure 5-1) into groove in transfer pump regulator assembly (74). Ensure 

that sleeve seal is seated completely. 

(29) Position piston (77) in transfer pump regulating assembly (74) with open end of piston facing 

outward. 

NOTE 

Adjusting screw is fragile. Do not exert excessive downward force on hex 

wrench while installing adjusting screw. Failure to comply could result in 

damage to adjusting screw. 

(30) Install spring and adjusting screw (76, 75) into transfer pump regulating assembly (74). Tighten 

adjusting screw until adjusting screw is 1-2 threads below flush with end of sleeve of transfer 

pump regulator housing. 

(31) Install inlet filter screen (73) on transfer pump regulator assembly (74). 

(32) Install regulator assembly (1, Figure 5-43) on hydraulic head (3) by aligning locating pin (2) with 

hole (4). 

FIGURE 5-43. REGULATOR ASSEMBLY INSTALLATION (TYPICAL). 

(33) Apply thin coating of grease to beveled surface on inside of transfer pump end cap (72, Figure 5-

1) and to threads of transfer pump end cap. 

(34) Position transfer pump end cap (72) on hydraulic head assembly. Rotate transfer pump end cap 

counterclockwise until "click" is heard, then rotate transfer pump end cap clockwise until hand 

tight. 

(35) Position governor arm (55) in fuel injection pump housing with linkage hook (56) hanging over 

side of fuel injection pump housing. 
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(36) Orient pivot shaft (54) with knife edge facing transfer pump end of fuel injection pump housing. 

Carefully install pivot shaft (54) into fuel injection pump housing and through openings in 

governor arm (55). 

(37) Position O-ring seals (53) on pivot shaft (54) and install pivot shaft nuts (52) finger tight. 

NOTE 

Finish torque sequence with shaft nut on linkage hook side of pump. 

(38) Torque each pivot shaft nut (52) alternately to 20 to 25 lb-in. (2.3 to 2.8 Nm). 

(39) Invert head and rotor assembly and install governor weights (1, Figure 5-44) into weight retainer 

(2) with rounded "heels" of governor weights in corners of weight retainer sockets. 

FIGURE 5-44. GOVERNOR WEIGHT INSTALLATION (TYPICAL). 

(40) Install thrust washer (Figure 5-45) so that thrust washer is resting on top of governor weight 

(1, Figure 5-44) "toes". 

FIGURE 5-45. THRUST WASHER INSTALLATION (TYPICAL). 
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(41) Install thrust sleeve (Figure 5-46). 

FIGURE 5-46. THRUST SLEEVE INSTALLATION (TYPICAL). 

(42) Install fuel injection pump housing on mounting plate (Refer to Appendix F, Figure F1) and 

secure in vice with hydraulic head bore tilted downward approximately 30-45 degrees. 

(43) Rotate drive shaft until drill point (1, Figure 5-47) on end is in 6 o’clock position. Apply light 

coating of lubricant (22204) to hydraulic head seal (87, Figure 5-1) and to entrance to fuel 

injection pump housing. 

FIGURE 5-47. HEAD AND ROTOR ASSEMBLY INSTALLATION (TYPICAL). 
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(44) Align drill point (2, Figure 5-47) in rotor with head locating screw bore at bottom of head. Align 

cam pin hole in cam ring (88, Figure 5-1) with head locating screw bore in hydraulic head. 

(45) Orient governor thrust sleeve (1, Figure 5-46) so that governor arm groove is in horizontal 

position. 

(46) Carefully slide head and rotor assembly into fuel injection pump housing with metering valve bore 

(3) at the 12 o’clock position (straight up). When hydraulic head seal contacts fuel injection pump 

housing, push head and rotor assembly in with slight twisting motion until head locking screw 

bore in head and rotor assembly aligns with head locating screw bore in fuel injection pump 

housing. 

(47) Install vent wire assembly (47, Figure 5-1) into hydraulic head until it bottoms. Ensure that vent 

wire assembly does not protrude above surface of hydraulic head. 

(48) Install shim (45), spring (44), and metering valve arm (43). 

NOTE 

Rotate hydraulic head slightly counterclockwise to aid in installing linkage 

hook onto pin on metering valve arm. 

(49) Engage linkage hook (56) to cutout in governor arm (43) and fit linkage hook onto pin on 

metering valve arm (41). 

(50) Install head locking screws (23) finger tight. 

(51) Thread control spring bushing (1, Figure 5-48) onto control rod (2) until control spring bushing 

contacts control spring guide (3). Thread control spring (4) five full turns onto control spring 

guide. 

FIGURE 5-48. CONTROL SPRING INSTALLATION. 
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NOTE 

Ensure that cross loop on end of control spring is installed between tabs on 

governor arm. 

(52) Depress metering valve arm (43, Figure 5-1) and install control rod (1, Figure 5-49). Install 

control spring (2) over governor arm tabs (3). 

FIGURE 5-49. CONTROL ROD INSTALLATION. 

(53) Depress metering valve arm (43, Figure 5-1) and install seal washer (17) and control rod guide 

(16). Torque control rod guide to 70 to 80 lb-in. (8 to 9 Nm). 

(54) Install spring pin (15), O-ring (14), and slotted adjusting cap assembly (13). 

(55) Install droop control locking cap (Figure 5-50). 

FIGURE 5-50. DROOP CONTROL LOCKING CAP INSTALLATION. 
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(56) Install damper piston (2, Figure 5-51) and damper barrel (1). 

FIGURE 5-51. DAMPER BARREL AND PISTON 

(57) Install new spacer washer (7, Figure 5-1). Install O-ring (6) to throttle using seal protection tube 

(18338). 

(58) Install throttle shaft on right side of pump. Slide throttle shaft assembly into housing, lever 

pointing upwards through damper barrel bracket. Position throttle shaft lever in pump with fork 

straddling control rod and resting on flats of control spring bushing. Insert shaft through lever. 

Refer to figure 5-52. 

FIGURE 5-52. THROTTLE INSTALLATION 
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(59) Ensure the governor linkage gap is properly set up prior to calibration by performing the 

following: 

(a) Partially loosen the adjusting screw with wrench until the parts can move in relationship 

to one another but with some resistance. 

(b) Expand the linkage to the maximum gap. Refer to Figure 5-53. Insert thickness gap 

setting gage between the throttle shaft and the upright on the linkage hook. 

(c) While holding the throttle lever in the wide open throttle position, close the gap to the 

thickness of the gage, press the linkage hook upright flush against the gage and tighten 

the linkage hook locking screw. 

(d) Rotate the drive shaft 1/2 turn and recheck the gap to ensure it is within the specified 

tolerance. 

FIGURE 5-53. SETTING GOVERNOR LINKAGE GAP 

(60) Invert pump in vise. Install new seal to head locating screw and install head locating screw to 

pump finger tight. 
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(61) Assemble reed valve to power side piston hole plug with concave side (spot of yellow stain). 

Refer to Figure 5-54. 

FIGURE 5-54. REED VALVE ASSEMBLY 

(62) Install reed valve retaining screws. 

NOTE 

A dental pick or similar tool can be slipped under seal and rotated around 

circumference of piston to untwist this seal. 

(63) Install new advance piston ring seal (square cross section) to piston making sure that seal is not 

twisted in groove. Refer to Figure 5-55. 

FIGURE 5-55. PISTON AND PISTON RING SEAL 
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(64) Slide piston ring into its groove on piston exercising caution not to over expand ring. Refer to 

Figure 5-56. 

FIGURE 5-56. PISTON RING 

(65) Slide piston ring compressor tool, over end of piston, chamfered side facing piston ring. Refer to 

Figure 5-57. 

FIGURE 5-57. PISTON RING COMPRESSOR 
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(66) Install piston into power side piston hole plug and remove tool. Refer to Figure 5-58. 

FIGURE 5-58. PISTON IN POWER SIDE PISTON HOLE 

NOTE 

For clockwise rotation pumps, power side plug is marked on side of housing 

with "C". For counterclockwise rotation pumps, power side plug is 

marked on side of housing with "CC". 

(67) Install two new O-ring seals to power side piston hole plug and install assembly to advance bore. 

Refer to figure 5-59. 

FIGURE 5-59. POWER SIDE PISTON HOLE PLUG INSTALLATION 
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(68) Align pin hole in piston with hole in cam ring and install cam pin. Refer to Figure 5-60. 

FIGURE 5-60. ALIGNING PIN HOLE IN PISTON 

(69) Install two new O-ring seals (29, Figure 5-1) to the spring side piston hole plug. Assemble the 

trimmer screw (33), a new O-ring seal (34) and the locknut (32)(chamfered side facing seal) to 

spring side plug (28). 

(70) Assemble the advance spring guide (31) and the advance spring(s) (30) to the trimmer screw (33). 

(71) Install spring side plug assembly (28) to housing (1) and tighten to 455 to 505 lb-in (51.5 to 57.2 

Nm). 

(72) Use wrench to tighten the power side plug to 455 to 505 lb-in (51.5 to 57.2 Nm). 

(73) Install new seal (25) to cam pin hole plug (24) and install plug (24). Tighten to 75 to 100 lb-in 

(8.5 to 11.3 Nm). 

(74) Tighten head locating screw (24) to 180 to 220 lb-in (20.0 to 25.0 Nm). 

(75) Invert pump and holding fixture in vise and tighten the two head locking screws (23) to 180 to 220 

lb-in (20.0 to 25.0 Nm). 

(76) Using end cap wrench, tighten the transfer pump end cap (72) to 360 to 440 lb-in (41.0 to 50.0 

Nm). 

(77) Assemble the transfer pump end cap locking plate (21) and the new seal (22) to screw (20) and 

install locking plate assembly to hydraulic head (48). Tighten screw to 70 to 80 lb-in (7.9 to 9.0 

Nm). 

(78) If pump is not equipped with a torque screw, install torque screw hole plug and new seal and 

tighten to 75 to 100 lb-in (8.5 to 11.3 Nm). 
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5.4. SHORT BLOCK ASSEMBLY

5.4.1. CAMSHAFT ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Inspection Prior to Camshaft Removal.

(1) Remove timing gear cover, refer to paragraph 4.9.3. 

(2) Inspect camshaft gear for chipped, broken, or missing teeth. If camshaft gear has chipped, broken, 

or missing teeth, camshaft must be removed and the camshaft gear replaced. Refer to paragraph 

5.4.1.c. 

b. End Play Test.

(1) If not already performed, remove timing gear cover. Refer to paragraph 4.9.3. 

(2) Attach magnetic base of dial indicator to front plate. 

(3) Position dial indicator against end of camshaft and zero dial indicator. 

(4) Measure camshaft end play. Camshaft end play should be 0.003 - 0.009 in. (0.08 - 0.23 mm). If 

camshaft end play exceeds specifications camshaft must be removed from engine and inspected, 

refer to step c. 

(5) Remove camshaft, refer to step c, or install timing gear cover, refer to paragraph 4.9.3. 

c. Removal.

(1) If not done previously, remove engine. Refer to TM 9-6115-672-14. Install engine on vehicle 

engine stand (NSN 4910-01-016-1835 or equal), refer to paragraph 4.10. 

(2) If not done previously, drain engine oil and coolant, refer to TM 9-6115-672-14. 

(3) Remove rocker arm cover, refer to paragraph 4.7.1. 

(4) Measure valve lift for excessive wear, refer to paragraph 4.7.2. If valve lift shows excessive wear, 

cylinder head must be removed for inspection of cylinder block, cylinder head, and camshaft 

followers, refer to paragraph 4.7.4. 

(5) Lock engine at No. 1 TDC compression, refer to paragraph 4.7.2. 

(6) Remove rocker arm assembly and push rods, refer to paragraph 4.7.3. 
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(7) Inspect push rods. If push rods are bent or show excessive scuffing, cylinder head must be 

removed for inspection of cylinder block, cylinder head, and camshaft followers, refer to 

paragraph 4.7.4. 

(8) Remove timing gear cover, refer to paragraph 4.9.2. 

(9) Remove fuel supply pump, refer to paragraph 3.12.3. 

(10) Rotate engine gear train using Flywheel Turning Tool (JDG820) until bolts (6, Figure 5-61) 

behind camshaft gear (4) can be removed. Remove bolts. 

(11) Mark camshaft gear teeth and idler gear teeth with timing marks using white paint to insure proper 

positioning of camshaft during installation. 

NOTE 

If camshaft is going to be replaced with new camshaft, cylinder head must 

be removed and camshaft followers must be replaced. 

(12) Remove cylinder head, if necessary, refer to paragraph 4.7.4. 

(13) If cylinder head has been removed, tag and remove camshaft followers and fuel supply pump 

activator pin. 

NOTE 

Engine must remain in a position where camshaft followers rest against 

cylinder head and do not fall into engine crankcase. If camshaft followers 

fall into crankcase, cylinder head removal is required. 

(14) If cylinder head has not been removed, revolve engine on vehicle engine stand (NSN 4910-01-

016-1835 or equal) until camshaft followers (2, Figure 5-61) and fuel supply pump activator pin 

falls away from camshaft lobes. 

CAUTION

Do not allow camshaft lobes to drag in bushing or honed bores. Failure to 

comply could result in damage to camshaft, camshaft bushing, or camshaft 

honed bores. 

NOTE 

Rotate camshaft carefully to aid in removal. 

(15) Pull camshaft (1) straight up, out of cylinder block. 

(16) Remove thrust plate (3, Figure 5-61) from camshaft. 
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FIGURE 5-61. CAMSHAFT 
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CAUTION

Camshaft must be replaced if dropped or damaged. Do not allow camshaft 

to strike floor when removing camshaft gear. 

NOTE 

Camshaft gear must be removed if camshaft or camshaft gear is to be 

replaced. 

(17) If necessary, remove camshaft gear using press. Transfer painted timing mark from old camshaft 

gear to new camshaft gear. 

(18) Cover all openings to prevent entry of foreign material. 

d. Test.

(1) Remove camshaft, refer to step b. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Good general ventilation is normally adequate. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure must not exceed 30 psig (207 kPa). Eye protection 

required. 

(2) Clean camshaft in solvent. Dry camshaft with compressed air. 

(3) Inspect all camshaft lobes and journals for wear, damage, or pitting. Replace camshaft and 

camshaft followers if wear or damage is found. 
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(4) Measure camshaft bushing inner diameter and camshaft journal outer diameter as follows: 

(a) Measure and record camshaft journal outer diameter for each camshaft journal. Camshaft 

journal outer diameter should be 2.1997 - 2.2007 in. (55.872 - 55.898 mm). Replace 

camshaft and camshaft followers if any camshaft journal outer diameter is out of 

specifications. 

(b) Measure and record front camshaft bushing inner diameter. Front camshaft bushing inner 

diameter should be 2.2031 - 2.2042 in. (55.961 - 55.987 mm). Replace front camshaft 

bushing as follows if measurement is not within specification. 

1 Remove countersunk TORX®7 cap screw and install M8 X 1.25 tapered bottom 

leg from Camshaft Bushing Service Kit into hole that has chamfered screw and 

star washer. 

2 Install M8 X 1.25 flat bottom legs and Removing/Installing Plate to cylinder 

block so plate is parallel with front plate and centered over camshaft bore. 

Tighten legs and hex nuts securely. 

3 Insert Bushing Remover into camshaft bore so puller pilots in bushing inner 

diameter and Bushing Installer Screw extends through plate. 

CAUTION

Cylinder block bore is easily damaged. Cylinder block must be replaced if 

cylinder block bore is damaged. Ensure that puller is properly piloted 

before pulling bushing. Failure to comply could result in damage to 

cylinder block. 

4 Install thrust washer and hex nut. Tighten hex nut until bushing is free of block 

bore. Remove puller and discard bushing. 

5 Clean and inspect bore in cylinder block. Cylinder block must be replaced if 

cylinder block bore is damaged, refer to paragraph 5.4.7. 

6 Measure camshaft bore inner diameter with bushing removed. Camshaft bore 

inner diameter with bushing removed should be 2.3607 - 2.3617 in. (59.961 - 

59.987 mm). Replace cylinder block if camshaft bore inner diameter is out of 

specification, refer to Paragraph 5.4.7. 

7 Mark orientation of oil supply hole on front face of engine block and on bushing 

using permanent marker. 

8 Apply High Temperature Grease (Appendix E) to inner diameter and outer 

diameter of new bushing and to inner diameter of bushing bore. Slide bushing 

onto Bushing Installer so notched end of bushing will be toward front end of 

engine when installed. 

9 Thread Bushing Installer Screw into Removing/Installing Plate. Ensure that 

bushing is started, square in bore, and oil hole is aligned. 
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10 Tighten forcing screw until flange of bushing driver bottoms against face of 

block. 

11 Remove bushing tool from cylinder block. 

12 Check oil supply hole for correct alignment. If oil supply holes are not aligned, 

remove and discard bushing and install new bushing. 

(c) Measure and record camshaft bore inner diameter for each remaining camshaft bore. 

Camshaft bore inner diameter should be 2.3607 - 2.3617 in. (59.961 - 59.987 mm). 

Replace cylinder block if any camshaft bore inner diameter measurement is out of 

specification. 

(d) Calculate and record front camshaft journal-to-front camshaft bushing oil clearance by 

subtracting front camshaft journal outer diameter from front camshaft bushing inner 

diameter. Front camshaft journal-to-front camshaft bushing oil clearance should be 

0.0025 - 0.0045 in. (0.063 - 0.115 mm). Replace front camshaft bushing, refer to step c., 

or camshaft, refer to paragraph 5.4.1, as required if front camshaft journal-to-front 

camshaft bushing oil clearance is out of specification. 

(e) Calculate and record camshaft journal-to-camshaft bore oil clearance for each camshaft 

journal by subtracting camshaft journal outer diameter from camshaft bore inner 

diameter. Camshaft journal-to-camshaft bore oil clearance should be 0.0035 - 0.0055 in. 

(0.088 - 0.140 mm). Replace camshaft or cylinder block as required if camshaft journalto-front camshaft bushing oil clearance is out of specification. 

(5) Measure camshaft lobe height as follows: 

(a) Measure and record height at widest point on camshaft lobe and height at narrowest point 

on camshaft lobe using micrometer. Refer to Figure 5-62. 

FIGURE 5-62. MEASURING CAMSHAFT LOBE HEIGHT 

(b) Calculate and record camshaft lobe height by subtracting height at narrowest point on 

camshaft lobe from height at widest point on camshaft lobe. 
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(c) Record camshaft lobe height and compare with specifications given in Table 5-3. 

Table 5-3. Camshaft Lobe Height Specifications.

Camshaft Lobe Height = Widest lobe point measurement - Narrowest lobe point 

measurement 

Intake Valve Camshaft Lobe 

Height 

0.273 - 0.292 in. (6.93 - 7.42 mm) 

Exhaust Valve Camshaft Lobe 

Height 

0.266 - 0.286 in. (6.76 - 7.26 mm) 

 (d) Repeat steps a and b for all camshaft lobes. Replace camshaft and camshaft followers if 

any camshaft lobes are not within specifications. 

(e) Measure fuel supply pump camshaft lobe diameter using micrometer. Fuel supply pump 

camshaft lobe diameter should be 1.680 - 1.690 in. (42.67 - 42.93 mm). Replace 

camshaft and camshaft followers if fuel supply pump camshaft lobe diameter is not 

within specification. 

(6) Position camshaft thrust plate on camshaft and check clearance using a feeler gage. Camshaft 

thrust plate clearance should be 0.003 - 0.009 in. (0.08 - 0.23 mm). Replace camshaft thrust plate, 

camshaft, or both if clearance is not within specification. 

(7) Install camshaft, refer to step f. 

e. Replacement.

(1) Remove camshaft, refer to step c. 

(2) Perform test procedures, refer to step d. Replace camshaft if it fails any portion of test. 

(3) Install camshaft, refer to step f. 

f. Installation.

(1) Remove all covering installed during step c (18). 

(2) Ensure that engine is locked with No. 1 piston at TDC compression stroke using Timing Pin 

(JDE81-4). 

(3) If camshaft is being replaced, remove cylinder head and replace camshaft followers, refer to 

paragraph 4.7.4. 

(4) If necessary, install camshaft gear on camshaft as follows: 

(a) Support camshaft (1, Figure 5-61) under first bearing journal in hydraulic press. 

(b) Apply High Temperature Grease (Appendix E) to camshaft nose and camshaft gear inner 

diameter. 
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(c) Install woodruff key (5) in camshaft nose. 

(d) Position camshaft gear on camshaft nose with timing mark away from camshaft. 

Carefully press camshaft gear onto camshaft using a Tubular Driver until camshaft gear 

bottoms against camshaft shoulder. 

(5) Lubricate camshaft bearing journals and camshaft lobes with High Temperature Grease (Appendix 

E). 

(6) Position thrust plate (3) on camshaft (1). 

CAUTION

Do not allow camshaft lobes to drag in bushing or honed bores. Failure to 

comply could result in damage to camshaft, camshaft bushing, or camshaft 

honed bores. 

(7) Carefully position camshaft and thrust plate in cylinder block. Rotate camshaft during installation 

to avoid obstruction in any bore. Install thrust plate capscrews and tighten to 26 lb-ft (35 Nm). 

(8) Remove upper idler gear if not removed. Refer to paragraph 5.4.2. 

(9) Time the camshaft as follows: 

(a) With timing tool (JD254A) resting on nose of crankshaft and center of camshaft, turn 

camshaft until timing mark on camshaft gear aligns with timing tool. 

(b) Check injection pump gear timing with timing tool (JD254A) resting on nose of 

crankshaft and center of injection pump shaft. Timing mark (S6 for 6 cylinder) on 

injection pump drive gear must align with timing tool. 

(10) If removed, reinstall upper idler gear. Refer to paragraph 5.4.2. 

(11) Install fuel supply pump, refer to paragraph 3.12.3. 

(12) If cylinder head has been removed, install camshaft followers, fuel supply pump activator pin, and 

cylinder head, refer to paragraph 4.7.4. 

(13) Install push rods and rocker arm assembly, refer to paragraph 4.7.3. 

(14) Adjust valve clearance, refer to paragraph 4.7.2. 

(15) Install rocker arm cover, refer to paragraph 4.7.1. 

(16) Install timing gear cover, refer to paragraph 4.9.3. 

(17) Service lubrication system and coolant system, refer to TM 9-6115-672-14. 

(18) Install engine, refer to TM 9-6115-672-14. 
ARMY TM 9-2815-260-24 

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5.4.2. IDLER GEARS AND IDLER GEAR SHAFTS.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Idler Gear End Play and Backlash Test.

(1) Remove timing gear cover, refer to paragraph 4.9.3 

(2) Remove oil pan, refer to paragraph 4.5.3. 

(3) Measure idler gear end play as follows: 

(a) Using dial caliper, check end play of upper and lower idler gears. Refer to Table 5-4 for 

specifications. 

(b) Observe specifications for new end play and maximum acceptable end play. 

(4) Measure idler timing gear backlash as follows: 

(a) Using a dial indicator, measure backlash between timing gears. Refer to Table 5-4 for 

specifications. 

(1) Measure upper idler gear-to-camshaft gear. Refer to Table 5-4. 

(2) Measure upper idler gear-to-injection pump gear. Refer to Table 5-4. 

(3) Measure upper idler-to-crankshaft gear. Refer to Table 5-4. 

(4) Measure lower idler gear-to-crankshaft. Refer to Table 5-4. 

(5) Measure lower idler gear-to-oil pump gear. Refer to Table 5-4. 

(b) If backlash is not within specification, install new timing gears. 

Table 5-4. Camshaft and Timing Gear Train Specifications

Item Specification 

Upper Idler Shaft OD 2.7463 - 2.7471 in. (69.757 - 69.777 mm) 

Upper Idler Gear Bushing ID 2.7481 - 2.7493 in. (69.802 - 69.832 mm) 

Lower Idler Shaft OD 1.7495 - 1.7505 in. (44.437 - 44.463 mm) 

Lower Idler Gear Bushing ID 1.7515 - 1.7535 in. (44.489 - 44.539 mm) 

Upper and Lower Idler Gear End Play 0.0037 - 0.0057 in. (0.095 - 0.145 mm) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-54 

Table 5-4. Camshaft and Timing Gear Train Specifications - CONT.

Item Specification 

Oil Clearance: 

Upper Idler Gear Bushing-to-Shaft 0.0030 - 0.0049 in. (0.075 - 0.125 mm) 

Lower Idler Gear Bushing-to-Shaft 0.0010 - 0.0040 in. (0.026 - 0.102 mm) 

Timing Gear Backlash: 

Upper Idler Gear-to-Camshaft Gear 0.0030 - 0.0162 in. (0.077 - 0.412 mm) 

Upper Idler Gear-to-Injection Pump 

Gear 

0.0030 - 0.0162 in. (0.077 - 0.412 mm) 

Upper Idler Gear-to-Crankshaft Gear 0.0025 - 0.0127 in. (0.065 - 0.322 mm) 

Lower Idler Gear-to-Crankshaft Gear 0.0026 - 0.0132 in. (0.067 - 0.336 mm) 

Lower Idler Gear-to-Oil Pump Gear 0.0032 - 0.0135 in. (0.081 - 0.342 mm) 

b. Removal.

(1) Remove timing gear cover, refer to paragraph 4.9.3 

(2) Remove oil pan, refer to paragraph 4.5.3. 

(3) Remove bolt (1, Figure 5-63) and thrust washer (2) securing upper idler gear (3) to shaft (5); 

remove idler gear (3). 

(4) Remove nut (8), washer (9), and thrust washer (10) securing lower idler gear (11); remove idler 

gear (11). 

(5) If necessary, use an arbor press and remove bushings (4 and 12) from gears (3 and 11). 

(6) Remove bolt (13) and washer (14) from lower idler gear shaft (15). 

(7) Remove lower idler gear shaft (15) from front plate using a pry bar. Remove thrust washer (17). 

(8) Remove upper idler gear shaft (5) from front plate using a pry bar. Remove thrust washer (7). 

(9) Remove spring pins (6 and 16) from shafts. 
ARMY TM 9-2815-260-24 

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FIGURE 5-63. IDLER GEARS 

c. Test.

(1) Measure upper and lower sleeve bushing (4 and 12, Figure 5-63) inner diameter. Refer to Table 5-

4 for specifications. 

(2) Measure upper and lower shaft (5 and 15) outer diameter. Refer to Table 5-4 for specifications. 

(3) Oil clearance is required between upper and lower bushing to shaft. Refer to Table 5-4 for 

specifications. If oil clearance exceeds limit, replace worn parts. 

(4) If necessary, replace worn idler gears (3 and 11 Figure 5-63), shaft (5 and 15) or bushing (4 and 

12). 

(5) If sleeve bushings (4 and 12) were removed, use an arbor press, driver and handle to install sleeve 

bushing (4) in idler gear (3) and sleeve bushing (12) in idler gear (11). 
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d. Installation.

(1) Install spring pins (6 and 16, Figure 5-63) with end pin protruding as shown in Figure 5-64. 

(2) Install upper thrust washer (7, Figure 5-63) and idler gear shaft (5) with spring pin (6) in notch. 

Drive shaft into front plate until thrust washer (7) is fully seated with oil hole facing up. Tighten 

capscrew (1) in engine block to 59 lb-ft (80 Nm). 

(3) Install lower thrust washer (17) and idler gear shaft (15) with spring pin (16) in notch. Drive shaft 

into front plate until thrust washer (17) is fully seated with oil hole facing up. Install capscrew 

(13) and washer (14) through rear of front plate and tighten to 59 lb-ft (80 Nm). 

(4) If sleeve bushings (4 and 12) were removed, use an arbor press, driver and handle to install sleeve 

bushing (4) in idler gear (3) and sleeve bushing (12) in idler gear (11). 

(5) Install lower idler gear (11), thrust washer (10), washer (9) and nut (8). 

(6) Time camshaft and install upper idler gear (3), thrust washer (2) and capscrew (1). Refer to 

paragraph 5.4.1. 

(7) Install oil pan, refer to paragraph 4.5.3. 

(8) Install timing gear cover, refer to paragraph 4.9.3. 

FIGURE 5-64. SPRING PIN PROTRUSION 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

5-57 

5.4.3. FRONT PLATE.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

(1) Remove timing gear cover, refer to paragraph 4.9.3. 

(2) Remove camshaft, refer to paragraph 5.4.1. 

(3) Remove fuel injection pump and drive gear, refer to paragraph 4.6.1. 

(4) Remove oil pump and drive gear, refer to paragraph 5.4.8. 

(5) Remove idler gears, refer to paragraph 5.4.2. 

(6) Remove six TORX screws (3, Figure 5-65) securing front plate (2); remove front plate (2). 

(7) Remove threaded studs (1). 

(8) Remove oil bypass valve, refer to paragraph 5.4.9. 

FIGURE 5-65. FRONT PLATE 
ARMY TM 9-2815-260-24 

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5-58 

b. Inspection.

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure must not exceed 30 psi (207 kPa). Eye protection 

required. 

(1) Remove all old sealant material from front plate and engine block. 

(2) Clean plate with soapy water and compressed air. Wipe front face of engine block with a cleaning 

cloth. Ensure sealant surface on engine block is clean. 

(3) Inspect front plate for wear or damage. Replace if necessary. 

c. Installation.

NOTE 

Apply thread lock (LOCTITE 242) to threads of studs (1, Figure 5-66) 

before installing front plate. 

CAUTION

Replacement front plates are supplied without injection pump timing mark. 

It is extremely important that timing mark be accurately transferred from 

original front plate to replacement plate in the exact location for correct 

injection pump timing. 

(1) Transfer injection pump timing pump mark from original front plate onto replacement plate, as 

follows: 

(a) Position locally manufactured template (Figure F2, Appendix F) on front plate and secure 

with three 3/8-16 capscrews. 

(b) Transfer injection pump timing mark from previous front plate onto template using a fine 

tip marker and straightedge. Remove template from front plate being replaced. 

(c) Attach template (with timing mark) to new front plate and tighten capscrews securely. 

(d) Transfer timing mark from the template to the new front plate using a scribe. Scribe deep 

enough so mark becomes a permanent reference. 

(e) Remove template from front plate. 

(2) Install oil bypass valve (1, Figure 5-89) and spring (2) in engine block bore. 

(3) Apply Flexible Form-In-Place Gasket in a continuous 1.5 to 2.0 mm bead (A) to cylinder block. 

Refer to Figure 5-66. 

(4) Locate bead in the center of the mating surfaces and completely encircle bolts and bolt holes. 
ARMY TM 9-2815-260-24 

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CAUTION

For flexible gasket to seal properly, tighten screws to specified torque using 

a cross pattern within 10 minutes after parts are assembled. 

(5) Install front plate (2, Figure 5-65). 

(6) Secure front plate (2) with six TORX screws (3). Tighten screws to 18 lb-ft (25 Nm). 

(7) Install threaded studs (1). Tighten studs to 26 lb-ft (35 Nm). 

(8) Install idler gears, refer to paragraph 5.4.2. 

(9) Install oil pump and drive gear, refer to paragraph 5.4.8. 

(10) Install fuel injection pump and drive gear, refer to paragraph 4.6.1. 

(11) Install camshaft, refer to paragraph 5.4.1. 

(12) Install timing gear cover, refer to paragraph 4.9.3. 

FIGURE 5-66. FRONT PLATE SEALANT APPLICATION 

5.4.4 CRANKSHAFT AND MAIN BEARINGS.

NOTE 

Before removing crankshaft, check crankshaft end play, refer to paragraph 

5.4.4 b. 

a. Removal.

(1) Remove oil pan, refer to paragraph 4.5.3. 
ARMY TM 9-2815-260-24 

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5-60 

(2) Remove oil pump, refer to paragraph 5.4.8. 

(3) Remove rocker arm assembly, pushrods, and cam followers, refer to paragraph 4.7.3. 

(4) Remove front plate, refer to paragraph 5.4.3. 

(5) Remove flywheel housing, refer to paragraph 4.8.3. 

NOTE 

Leave front and rear main bearing caps installed until all of connecting rod 

caps have been removed. Push pistons and rods away from crankshaft. 

(6) Remove connecting rod bearing caps, refer to paragraph 5.4.5. 

(7) Check main bearing caps (3 and 4, Figure 5-67) for arrows (cast in bearing cap) and numbers 

stamped on cap and oil pan rail. Arrow points toward camshaft side of engine. If there are no 

numbers, stamp corresponding numbers on cap and oil pan rail. This will assure correct 

placement location of main bearing caps during reassembly. 

FIGURE 5-67. CRANKSHAFT AND MAIN BEARINGS 
ARMY TM 9-2815-260-24 

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(8) Remove capscrews (1) and washers (2) securing main bearing caps (3 and 4); remove main 

bearing caps. 

NOTE 

Visually inspect condition of bearing inserts (5 and 6) as main bearing caps 

are removed. Keep caps and inserts together and in correct order. 

(9) Check bearing (5 and 6) clearances as follows: 

(a) Place a strip of bearing gage (PLASTIGAGE) in the center of the main bearing cap about 

three fourths of width of bearing. 

(b) Use oil on bearing gage to prevent smearing. 

(c) Install cap and tighten capscrews (1) to 100 lb-ft (135 Nm). 

(d) Remove cap and compare width of bearing gage with scale provided, to determine 

clearance. Maximum permissible clearance is 0.0043 inch (0.109 mm). 

__________ 

WARNING

Crankshaft is very heavy, do not attempt to remove crankshaft by hand. 

Use proper lifting equipment. 

NOTE 

Use of bearing gage will determine wear, but will not determine condition 

of either bearing or journal. 

(10) Attach a nylon sling (or other suitable lifting sling) to journals of crankshaft (7). 

NOTE 

An alternate method of attaching sling is to install a capscrew on both ends 

of crankshaft and attach sling to screws. 

(11) Using proper lifting equipment, carefully raise crankshaft out of engine block. 

(12) Place crankshaft (7) on a clean flat surface and support journals with wooden blocks. 

(13) If bearings (5 and 6) are to be replaced, remove inserts from engine block. Otherwise, leave 

bearing inserts in block until assembled inner diameter has been measured. 

(14) Using an arbor press and gear puller, pull gear (8) from crankshaft (7). Remove key (9) from 

crankshaft. 
ARMY TM 9-2815-260-24 

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 b. Crankshaft End Play Test.

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Good general ventilation is normally adequate. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Pressure will not exceed 30 psi (207 kPa). Eye protection 

required. 

(1) Inspect gear (8, Figure 5-67) for wear or damage. 

(2) Check crankshaft end play as follows: 

NOTE 

It is recommended that crankshaft end play be measured prior to removing 

crankshaft to determine condition of thrust bearings. Crankshaft end play 

may also be checked at front end of crankshaft. 

(a) Position dial indicator on face of flywheel. 

(b) Push crankshaft as far to rear of engine as possible. 

(c) Zero dial indicator. 

CAUTION

Do not apply too much pressure with bar, as this could damage bearings. 

(d) Using a bar, gently pry crankshaft as far forward as possible. 

NOTE 

New thrust bearings will usually restore proper end play. If end play is not 

within specification on two piece flanged thrust bearings, install a two piece 

thrust bearing (without flange) and oversized thrust washers. 

(e) End play for new two piece thrust bearing, refer to Table 5-5 for values. 

c. Inspection.

(1) Inspect crankshaft per the following procedures: 

(a) Clean crankshaft using solvent and compressed air. 

(b) Inspect oil passages to make sure they are open. Use compressed air and a small piece of 

wire. 
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(c) Inspect crankshaft for any signs of load stress, cracks, scoring, or scratches on journals. 

(An inspection must be made if the crankshaft damper was found to be damaged or 

defective.) Figure 5-68 shows critical areas of load stress in a crankshaft. 

FIGURE 5-68. CRITICAL AREAS OF CRANKSHAFT LOAD STRESS 

NOTE 

When inspecting crankshaft for cracks, a method (such as the Fluorescent 

Magnetic Particle Method) must be used that is capable of detecting minute 

cracks that are not visible to the eye. This method magnetizes the crank, 

employing magnetic particles which are fluorescent and glow under black 

light. Replace crankshaft if cracks are found. The crankshaft must be 

demagnetized after the test. 

(d) Check each journal for evidence of excessive overheating or discoloration. If either 

condition exists, replace crankshaft since heat treatment has probably been destroyed. 

(2) Measure assembled inner diameter of bearings and outer diameter of crankshaft journals as 

follows: 

(a) With crankshaft out of engine block, install main bearing inserts and caps (be sure inserts 

are installed correctly). 

(b) Tighten main bearing capscrews. Refer to Table 5-5 for values. 

(c) Measure inner diameter of all bearings with an inside micrometer. Refer to Table 5-5 for 

values. 
ARMY TM 9-2815-260-24 

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5-64 

(d) Measure outer diameter of all respective main bearing journals at several points around 

journal. Refer to Table 5-5 for values. 

Table 5-5. Crankshaft and Main Bearings Specifications.

Item Specification 

Crankshaft End Play (Thrust Bearing Clearance) 

Engine With Two-piece Thrust Bearing 

0.002- 0.010 in. 

(0.05 - 0.25 mm) 

Main Bearing Journal OD 3.1229 - 3.1240 in. 

(79.324 - 79.350 mm) 

Main Bearing Assembled ID 3.1256 - 3.1273 in. 

(79.391 - 79.433 mm) 

Main Bearing-to-Journal Clearance 0.0016 - 0.0043 in. 

(0.041 - 0.109 mm) 

Main Bearing-to-Journal Width 1.5335 - 1.5365 in. 

(38.952 - 39.028 mm) 

Thrust Bearing Overall Width 1.527 - 1.530 in. 

(38.79 - 38.87 mm) 

Maximum Main or Rod Journal Taper 0.0004 in. (0.010 mm) 

Maximum Main or Rod Journal Out-of-Roundness 0.0002 in. (0.005 mm) 

Undersize Main or Rod Bearing Available (0.25 mm) (0.010 in.) 

Main Bearing Bore Specifications: 

ID Without Bearing Inserts 3.3250 - 3.3260 in. 

(84.455 - 84.481 mm) 

Bore Centerline-to-Top Deck of Block 13.3029 - 13.3059 in. 

(337.896 - 337.972 mm) 

Torque Values: 

Main Bearing Cap Screw 100 lb ft (135 Nm) 

Piston Cooling Orifices 8 lb-ft (11 Nm) 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

5-65 

NOTE 

If engine has previously had a major overhaul and undersized bearing 

inserts were used, above listed ID and OD dimensions may not be the same 

as those recorded. However, oil clearance should be within specifications. 

Oil clearance is 0.0016-0.0043 inch (0.041 to 0.109 mm). 

(e) Use crankshaft journal outer diameter measurements to determine if journal is out-ofround or tapered. Refer to Table 5-5 for journal out-of roundness wear limit and journal 

taper-per-inch of journal length wear limit. 

(f) If journals are tapered, out-of-round, scored, or damaged, crankshaft should be ground. 

Refer to paragraph (e). Proper undersize bearings should be installed after grinding. 

(3) Measure main thrust journal width and thrust bearing width, refer to Figure 5-69, as follows: 

(a) Measure width of main thrust journal with an inside micrometer. 

(b) Refer to Table 5-5 for new main thrust journal width. 

(c) If width is not within specification, recondition crankshaft and install an oversize thrust 

washer set. If width is correct, measure main thrust bearing width. 

(d) Measure width of thrust bearing using an outside micrometer. 

FIGURE 5-69. MEASURING MAIN THRUST JOURNAL AND THRUST BEARING WIDTH 

(e) Refer to Table 5-5 for new main thrust bearing width. 

(f) Refer to Table 5-5 for bearing-to-journal clearance. 
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5-66 

(4) Measure assembled inner diameter of main bearing caps as follows: 

(a) Remove bearing inserts from caps and engine block. Keep inserts in correct order if they 

are to be reused. 

(b) Clean caps in solvent and dry with compressed air. 

(c) Inspect caps for serviceability. Small burrs or nicks on flat surfaces may be removed 

with a file. Use a medium-grit polishing cloth to dress up curved bearing surfaces. 

(d) Install bearing caps in engine block. Refer to Table 5-5 for values. 

(e) Measure inner diameter of bore without bearings. Refer to Table 5-5 for main bearing 

bore inner diameter without bearings. 

(f) If bearing caps are damaged or bore is not within specification, replace cap and bore to 

specification. 

CAUTION

Main bearing cap line boring should be done only by experienced personnel 

on equipment capable of maintaining the bore specifications. Refer to 

Table 5-5 for dimension from centerline of bore-to-top of deck of engine 

block. 

NOTE 

Replacement bearing caps are supplied with bearing bore unfinished. 

(5) Inspect piston cooling orifices as follows: 

(a) Inspect each cooling orifice to make sure it is not plugged or damaged. 

(b) Use a soft wire and compressed air to clean orifice. Replace, if condition is questionable. 

CAUTION

A piston cooling orifice failure could cause damage to pistons, piston pins, 

rod pin bushings, and liners. If a piston cooling orifice is left out of block 

during assembly, low or no oil pressure will result. 

(c) Install all the orifices and tighten to values in Table 5-5. 
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5-67 

d. Repair.

NOTE 

If crankshaft is to be reground, use following recommended guidelines. 

CAUTION

Crankshaft grinding should be done only by experienced personnel on 

equipment capable of maintaining crankshaft size and finish specifications. 

CAUTION

If undersize bearings are used, check bearing clearance after bearing caps 

have been tightened to specified torque. If undersize bearings are too tight 

and clearance is not within specifications, journals and bearing will be 

wiped clean of all oil. This would result in premature wear of parts. 

CAUTION

When grinding crankshaft, also grind fillet radii to specifications. This is 

necessary to prevent stress risers in fillet areas during grinding. 

NOTES 

Refer to Table 5-5 for undersize main and connecting rod bearings. 

To maintain the correct end play, the two piece main bearing with three 

piece thrust washer set can be used to replace the two piece flanged main 

bearings if desired. 

(1) Compare crankshaft journal measurements taken during inspection and determine size which 

journals are to be reground. 

(2) If one or more main or connecting rod journals requires grinding, then grind all of main journals 

or all of connecting rod journals to same required size. Grind clockwise (opposite engine 

rotation). 

(3) All journal fillets radii must be free of any sharp grind marks or scratches. Fillet must blend 

smoothly into journal and crank cheek. Radius may be checked with a fillet gage. 

(4) Care must be taken to avoid localized heating which often produces grinding cracks. Use coolant 

generously to cool crankshaft while grinding. Do not crowd grinding wheel into work. 

(5) Polish or lap (counterclockwise) ground surfaces to specified finish. Reground journals will be 

subject to excessive wear unless polished smooth. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

5-68 

NOTE 

When thrust surfaces are reground and an oversize washer is used, 

crankshaft end play specification must be maintained. 

(6) If thrust surfaces of crankshaft are worn or grooved excessively, they must be reground and 

polished. Care must be taken to maintain specified radius between each thrust surface and bearing 

journal. An oversize thrust washer set is available. 

(7) Stone edge of all oil holes in journal surfaces smooth to provide a radius of approximately 0.060 

inch (1.50 mm). 

(8) After grinding has been completed, inspect crankshaft by fluorescent magnetic particle method, or 

other similar method to determine if cracks have originated due to grinding operation. 

(9) Demagnetize crankshaft. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/ prolonged contact. 

Good general ventilation is normally adequate. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Pressure will not exceed 30 psi (207 kPa). Eye protection 

required. 

(10) Thoroughly clean crankshaft and oil passages with solvent. Dry with compressed air. 

e. Installation.

(1) Install gear (8, Figure 5-67) on crankshaft as follows: 

__________ 

WARNING

Oil fumes or oil can ignite above 380°F (193°C). Use a thermometer and do 

not exceed 360°F (182°C). Do not allow a flame or heating element to be in 

direct contact with oil. Heat oil in a well ventilated area. Plan a safe 

handling procedure to avoid burns. Wear protective clothing, gloves, 

apron, etc. 

(a) Heat gear (8), in oil, to 300°F (148°C). 

(b) Install Adapter on nose of crankshaft (7). Tighten capscrews securely. 
ARMY TM 9-2815-260-24 

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5-69 

NOTE 

When installing gear, do not gouge or nick crankshaft flange or wear sleeve. 

(c) Place gear on crankshaft flange. Be sure woodruff key (9) is properly aligned with 

keyway in gear (8). 

(d) Install Installer over adapter. 

(e) Tighten nut clockwise until gear firmly seats against crankshaft flange. Allow gear to 

cool before removing installer. 

(2) Install main bearing (6) inserts. Make sure that tang on inserts is engaged with slot in engine 

block and main bearing caps. Also make sure that oil holes line up with oil passages in block. 

CAUTION

If new thrust bearing inserts or thrust bearing washers are installed, they 

must be installed as a set. 

(3) Install main thrust bearing (5) in rear web of engine block. 

(4) Apply a liberal coating of clean engine lubricating oil to bearing surfaces and crankshaft journals. 

(5) Using proper lifting equipment, lower crankshaft (7) onto main bearings. 

(6) Dip entire bearing capscrews (1) in clean engine lubricating oil (MIL-L-2104) and position them 

in the main bearing caps. Apply a liberal amount of oil to bearing inserts in caps. 

NOTE 

Make sure bearing caps are installed on the bearing bosses from which they 

were removed. The numbers stamped on the caps should be on the same 

side as the numbers on the block. If there is an arrow on cap, arrow must 

point toward camshaft side of block. 

(7) Install each bearing cap (3 and 4), bearings (5 and 6), and capscrews (1) with washers (2) with the 

recesses and tags aligned in matching order. Make sure bearing tabs also match up before 

tightening capscrews. 

CAUTION

Do not use pneumatic wrench to install main bearing capscrews, as damage 

may occur to the threads. 

 

(8) Before tightening capscrews on main bearing caps, align upper and lower thrust washers or 

flanges on main thrust bearings (5). Using a soft-face hammer, tap crankshaft to the rear and then 

to the front to line up thrust bearing surfaces. 

(9) Tighten all capscrews to values in Table 5-5. 
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(10) Turn crankshaft (7) by hand. If it does not turn easily, disassemble parts and determine the cause. 

CAUTION

Using pneumatic wrenches to install capscrews may cause damage to the 

threads. Never reuse connecting rod capscrews. 

(11) Install connecting rod caps and bearings. Use new capscrews and tighten to specification. Refer 

to paragraph 5.4.5. 

(12) Check crankshaft for specified end play, refer to paragraph 5.4.2. 

(13) Install flywheel housing, refer to paragraph 4.8.3. 

(14) Install front plate, refer to paragraph 5.4.3. 

(15) Install rocker arm assembly, pushrods, and cam followers, refer to paragraph 4.7.3. 

(16) Install oil pump, refer to paragraph 5.4.8. 

(17) Install oil pan, refer to paragraph 4.5.3. 

5.4.5. PISTONS AND CONNECTING RODS.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

The following procedure is provided for removal of the pistons and connecting rods. 

(1) Drain coolant and lubrication system, refer to TM 9-6115-672-14. 

(2) Remove cylinder head, refer to paragraph 4.7.4. 

(3) Remove camshaft followers, refer to paragraph 5.4.1. Ensure that camshaft followers are kept in 

order for reassembly into the same position. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure must not exceed 30 psi (207 kPa). Eye protection 

required. 

(4) Thoroughly clean all gasket surfaces. Remove all old gasket material, corrosion, carbon, and 

other foreign material from top deck. Use compressed air to remove loose material. 
ARMY TM 9-2815-260-24 

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5-71 

CAUTION

Cap screws and washers must be tightened to correct specification to 

achieve an accurate reading when checking liner standout (height above 

block), as detailed later in this paragraph. 

(5) Use short capscrews (1, Figure 5-70) and 1/8 in. (3 mm) thick washers (2) to bolt down cylinder 

liners (3). Fasten each liner in two locations. Tighten capscrews to 50 lb-ft (68 Nm). 

FIGURE 5-70. FASTENING CYLINDER LINERS. 

NOTE 

Do not rotate crankshaft with cylinder head removed unless liners are 

fastened down. 

(6) Remove carbon from liner bore using scraper or ridge reamer, refer to Figure 5-71. Rotate 

crankshaft as required to allow clearance for scraper or ridge reamer. Use compressed air to 

remove loose material. 

FIGURE 5-71. REMOVING CARBON FROM CYLINDER LINER. 
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5-72 

(7) Remove oil pan, refer to paragraph 4.5.3. 

(8) Remove oil pump and outlet tube, refer to paragraph 5.4.8. 

(9) Mark rods (5, Figure 5-72), pistons (4), and rod caps (2) to insure correct assembly in same 

location. 

CAUTION

Ensure that bearings are kept with same rod caps and rods from which 

they are removed. Failure to comply could result in excessive engine wear. 

(10) Remove capscrews (1), rod cap (2) and rod cap bearing (3). 

NOTE 

Use PLASTIGAGE as directed by the manufacturer. PLASTIGAGE will 

determine bearing-to-journal oil clearance, but will not indicate the 

condition of either surface. 

(11) Measure rod bearing (6) to crankshaft oil clearance using PLASTIGAGE before removing piston 

(4) and rod (5). Record measurements. Refer to paragraph 5.4.5.b.2(h). 

CAUTION

Hold on to piston to prevent piston from dropping. Piston will drop once 

piston rings have cleared cylinder liner. Failure to comply could result in 

damage to piston or rod. 

CAUTION

Do not allow rod to hit cylinder liner bore when removing piston and rod 

assembly. Failure to comply could result in damage to cylinder liner. 

(12) Gently tap bottom of piston (4) until piston is clear of cylinder block. Remove piston (4) and rod 

(5) assembly. Remove rod bearing (6). 

(13) Repeat steps 9-12 for all cylinders. 

(14) Cover all openings to prevent entry of foreign material. 

b. Repair.

The following procedure is provided for repairing the pistons and connecting rods. Remove pistons and 

connecting rods (refer to paragraph step a. above) and place on a suitable workbench. Disassemble per the 

following steps: 

(1) Disassemble the pistons per the following steps: 

(a) Remove piston (4, Figure 5-72), refer to step a. 

(b) Remove piston rings (7) using Piston Ring Expander. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-73 

(c) Remove snap rings (8) using snap ring pliers. Discard snap rings. 

(d) Remove piston pin (9) and rod (5). 

(2) Test the pistons and connecting rods per the following steps: 

(a) Clean piston ring grooves using piston ring groove cleaning tool. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure must not exceed 30 psi (207 kPa). Eye protection 

required. 

CAUTION

When washing pistons, always use a stiff bristle brush, not a wire brush, to 

loosen carbon residue. Failure to comply could result in damage to pistons. 

(b) Clean pistons (4, Figure 5-72) with hot water and liquid detergent. Soak pistons in a 

solution of 50 percent liquid household detergent and 50 percent hot water for 30 to 60 

minutes. Use stiff bristle brush to loosen carbon residue. Dry with compressed air. 

(c) Carefully inspect pistons (4) under magnification. Check for the following: signs of fatigue, 

fine cracks in piston head (1, Figure 5-73), bent or broken ring lands (2), cracks in skirt (3) at 

inner and outer ends of piston pin bore, and excessive piston skirt wear. (Original machining 

marks must be visible.). If any imperfections are found, replace piston (4) and cylinder liner 

(11, Figure 5-72), refer to paragraph 5.4.6, as a set. 

(d) Check piston ring groove wear as follows: 

1 Check wear of keystone ring groove (top groove) using Ring Groove Wear 

Gauge (JDE62). Check groove at several locations around circumference of 

piston. Gauge shoulders should not contact ring land. Clearance (1, Figure 5-

74) between shoulders of Ring Groove Wear Gauge (2) and ring land indicate 

ring groove is good. If ring groove is worn, replace piston (4, Figure 5-72) and 

cylinder liner (11), refer to paragraph 5.4.6, as a set. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-74 

FIGURE 5-72. PISTONS, CONNECTING RODS, AND CYLINDER LINERS. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-75 

FIGURE 5-73. PISTON INSPECTION (DEFECTS EXAGGERATED) 

FIGURE 5-74. CHECKING PISTON KEYSTONE RING GROOVE WEAR. 

2 Check second and third piston grooves using new piston ring (7, Figure 5-72) 

and feeler gauge, refer to Figure 5-75. Check clearance at several points. Ring 

groove clearance should not exceed 0.008 in. (0.20 mm). If clearance exceeds 

specification, replace piston (4, Figure 5-72) and cylinder liner (11), refer to 

paragraph 5.4.6, as a set. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-76 

FIGURE 5-75. MEASURING PISTON RING GROOVE CLEARANCE. 

(e) Measure piston pin bore inner diameter. Piston pin bore inner diameter should be 1.6254 

- 1.6258 in. (41.285 - 41.295 mm). If piston pin bore inner diameter exceeds 

specifications, replace piston and cylinder liner, refer to paragraph 5.4.7, as a matched 

set. 

(f) Measure and record piston skirt diameter (1, Figure 5-76) 90 degrees off piston pin bore 

and 1.1 in. (28 mm) from bottom of piston (2). Piston skirt diameter should be 4.188 - 

4.189 in. (106.38 - 106.40 mm). If piston skirt diameter exceeds specifications, replace 

piston and cylinder liner, refer to paragraph 5.4.6, as a set. 

FIGURE 5-76. MEASURING PISTON SKIRT 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-77 

(g) Inspect piston pin as follows: 

CAUTION

Piston pin has a highly polished surface. Do not attempt to polish or 

refinish piston pin. Failure to comply could result in excessive piston wear. 

1 Visually inspect piston pin for wear or damage. Replace piston pin if worn or 

damage is observed. 

2 Measure piston pin outer diameter using outer diameter micrometer. Piston pin 

outer diameter should be 1.6243 - 1.6252 in. (41.257 - 41.280 mm). Replace 

piston pin if measurement is out of specifications. 

3 Dip piston pin in clean engine oil. 

4 Install piston pin through piston. Piston pin should pass through piston using 

only light thumb pressure. 

5 Insert piston pin from both sides. If piston pin enters freely, but binds in the 

center, replace piston and cylinder liner, refer to paragraph 5.4.6, as a set. 

6 Insert piston pin to check for bore alignment. If piston pin clicks or needs to be 

forced into bore on opposite side, replace piston and cylinder liner, refer to 

paragraph 5.4.6, as a set. 

(h) Inspect connecting rod as follows: 

1 Inspect rod bearings for damage. Replace rod bearings if damage is observed. 

2 Measure and record crankshaft (7, Figure 5-67) journal outer diameter at several 

points. Compare crankshaft journal outer diameter with specifications given in 

Table 5-6. Replace crankshaft (7) if out of specifications. 

Table 5-6. Connecting Rod Journal and Bearing Specifications.

Item Specification 

Crankshaft Journal OD 3.0629 - 3.0640 in. (77.800 - 77.826 mm) 

Assembled Rod Bearing ID 3.0659 - 3.0679 in. (77.876 - 77.927 mm) 

Rod Bearing-to-Journal 

 Oil Clearance (new parts) 0.0020 - 0.0050 in. (0.050 - 0.127 mm) 

Rod Bearing-to-Journal 

 Oil Clearance (used parts) 0.0020 - 0.0600 in. (0.050 - 0.152 mm) 

3 Assemble connecting rod (5, Figure 5-72), cap (2), and bearings (3 and 6) using 

old capscrews (1). Torque capscrews to 50 lb-ft (68 Nm). Tighten capscrews an 

additional 90 degrees (1/4 turn). 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-78 

4 Measure and record assembled rod bearing inner diameter. Compare assembled 

rod bearing inner diameter with specifications given in Table 5-6. Replace 

bearings (3 and 6) if out of specifications. 

5 Subtract crankshaft journal outer diameter from rod bearing inner diameter to 

determine oil clearance. Compare oil clearance calculations with specifications 

given in Table 5-6. Replace bearings (3 and 6), connecting rod (5) or crankshaft 

(7, Figure 5-67) as required if out of specifications. 

6 Remove capscrews (1, Figure 5-72), cap (2), and bearings (3 and 6). 

7 Inspect connecting rod (5) and cap (2) for wear or damage, such as chips or 

cracks in the joint area. Inspect in and around capscrew (1) holes in cap. 

Replace connecting rod and cap if any imperfections are found. 

NOTE 

Assemble rod and cap without bearings installed. 

8 Assemble connecting rod (5) and cap (2) using old capscrews (1). Torque 

capscrews to 43 lb-ft (58 Nm). Tighten capscrews an additional 90 degrees (1/4 

turn). 

9 Measure and record assembled connecting rod bore inner diameter at center of 

bore as follows: 

a At right angle to connecting rod-to-cap joint. 

b At 45 degrees left of measurement step a. 

c At 45 degrees right of measurement step a. 

(i) Compare connecting rod bore inner diameter with specifications given in Table 5-7. 

Replace connecting rod (5) and cap (2) if out of specifications. 

Table 5-7. Connecting Rod Bore (Without Bearing Inserts) Specifications.

Item Specification 

Rod Bore ID 3.2550 - 3.2560 in. (82.677 - 82.703 mm) 

Maximum Permissible Bore Out-ofRound 0.0015 in. (0.038 mm) 

 (j) Subtract smallest rod bore inner diameter measurement from largest rod bore inner 

diameter measurement. This is the maximum bore out-of-round measurement. Replace 

connecting rod (5) and cap (2) if maximum bore out-of-round measurement exceeds 

specifications given in Table 5-7. 

(k) Measure connecting rod (5) piston pin bushing (10) inner diameter and compare with 

specifications given in Table 5-8. Replace connecting rod piston pin bushing if out of 

specifications, refer to step m. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-79 

Table 5-8. Connecting Rod Piston Pin Bushing Specifications.

Item Specification 

Connecting Rod Piston Pin Bushing 

ID 

1.6260 - 1.6290 in. (41.300 - 41.376 mm) 

Piston Pin-to-Bushing Oil Clearance 0.0007 - 0.0040 in. (0.020 - 0.102 mm) 

 (l) If necessary, replace connecting rod piston pin bushing in straight pin-end rod as follows: 

CAUTION

Oil holes must be aligned. If holes are not aligned, remove and discard 

bushing. Install a new bushing. DO NOT attempt to reuse the bushing. 

Install bushing in rod. 

1 Use driver for 1.6 in. (41 mm) pin to install bushing. 

2 Press bushing into rod bore until edge of bushing is flush or just slightly below 

machined surface on face of rod. 

3 Remove rod from press. 

4 inner diameter of bushing must be precision bored to proper size. Pin-toBushing oil clearance should be 0.0007 - 0.0022 in. (0.020 - 0.056 mm) and 

wear limit should be 0.0040 in. (0.102 mm). 

(m) Calculate piston pin-to-bushing oil clearance by subtracting piston pin (9) outer diameter 

from connecting rod piston pin bushing (10) inner diameter. Compare piston pin-tobushing oil clearance with specifications given in Table 5-8. Replace connecting rod 

piston pin bushing, refer to step l, or piston pin if out of specifications. 

(n) Insert piston pin (9) from either side of connecting rod piston pin bushing (10). Replace 

connecting rod piston pin bushing, refer to step l, if piston pin is free on one end but tight 

on the other, or if piston pin enters freely from both sides, but is tight in the center. 

(o) Measure rod center-to-center bore as follows; 

1 Measure rod center-to-center bores (with bushings removed). Bearing bore-topin bushing (center-to-center) length A should be 7.990 - 7.994 in. (202.95 - 

203.05 mm). Refer to Figure 5-77. 

2 Replace rod if not within specifications. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-80 

FIGURE 5-77. MEASURING ROD CENTER-TO-CENTER BORES 

(3) Assemble the pistons and connecting rods per the following steps: 

NOTE 

If new piston and liner assembly is to be installed, leave piston inside liner. 

Push piston out of liner bottom only far enough to install piston pin. 

(a) Lubricate piston pin (9, Figure 5-72),connecting rod piston pin bushing (10), and piston 

pin bore in piston (4) with clean engine oil. 

CAUTION

Install pistons on same connecting rods as pistons were removed from. Use 

new piston pin snap rings. Failure to comply could result in excessive 

engine wear or engine failure. 

(b) Assemble piston (4) and matching connecting rod. Ensure that the word "FRONT" on 

side of piston and side of connecting rod are facing same direction.. 

(c) Insert piston pin into piston pin bore in piston and through connecting rod piston pin 

bushing. 

(d) Install new snap rings (8) with sharp edge of ring facing away from piston pin. Ensure 

that snap rings are seated in grooves of piston pin bore. 

CAUTION

Do not over expand piston rings. Piston rings can be damaged if expanded 

too far. Expand piston rings only as far as necessary to install rings on 

piston. Failure to comply could result in engine failure. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-81 

NOTE 

Piston rings come pre-installed in new piston and liner assemblies. Leave 

piston inside liner. 

(e) Install piston rings as follows: 

1 Install oil ring expander in bottom ring groove of piston (4) using piston ring 

expander. Position end gap of oil ring expander toward either side of piston pin. 

2 Install oil control ring (7c.) in bottom ring groove over ring oil ring expander. 

Position end gap of oil control ring on opposite side of piston from oil ring 

expander gap. 

3 Identify top side of compression rings (7a. and 7b.). Top side of rectangular and 

keystone compression rings are identified by depression marks on top side of 

two rings. 

4 Install rectangular compression ring (7b.) in center ring groove of piston (4) 

with depression marks facing top of piston. 

5 Position gap in rectangular compression ring (7b.) on opposite side of piston 

from gap in oil control ring (7c.). 

6 Install keystone compression ring (7a.) in top ring groove of piston (4) with 

depression marks facing top of piston. 

7 Position gap in keystone compression ring (7a.) on opposite side of piston from 

gap in rectangular compression ring. 

(f) Measure piston protrusion as follows: 

1 Press down on top of piston (4) to remove oil clearances before measuring 

piston protrusion. 

2 Position gauge on cylinder block. Zero dial indicator against cylinder block. 

3 Position gauge across piston. While pressing gauge downward, rotate 

crankshaft until piston is at Top Dead Center (TDC) position. 

4 Measure piston height at several positions around piston. Piston Protrusion 

(above cylinder block deck) should be 0.003 - 0.012 in. (0.08 - 0.30 mm). 

(g) If piston protrusion is out of specifications, check dimensions of piston, cylinder block, 

crankshaft, and bearings to determine the cause. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-82 

c. Installation.

(1) Assemble piston assembly, refer to paragraph d. 

(2) Remove all covering installed during step a (14). 

(3) Coat piston (4, Figure 5-72), piston liner (11), and Piston Ring Compressor (JDE84) with clean 

engine oil. 

(4) Carefully position piston and connecting rod assembly inside Piston Ring Compressor (JDE84). 

(5) Carefully place Piston Ring Compressor (JDE84) with piston and connecting rod over piston liner 

so the word "FRONT" on side of rod and on side of piston faces toward front of engine. Push 

piston into piston liner. 

(6) Position bearing insert (6) in connecting rod (5) from bottom of cylinder block. Ensure that tang 

of bearing insert is firmly seated in groove of connecting rod. 

(7) Apply clean engine oil to bearing insert (6) and crankshaft journal. Carefully pull connecting rod 

(5) and bearing insert against crankshaft journal. 

(8) Install bearing insert (3) in cap (2). Ensure that tang of bearing insert is firmly seated in groove of 

cap. 

(9) Apply clean engine oil to bearing insert (3). Install cap (2) on connecting rod (5) with tangs to 

same side. 

CAUTION

Always use new capscrews for final assembly of connecting rod and cap. If 

capscrews have been tightened before, do not reuse for final assembly. 

Failure to comply could result in engine failure. 

(10) Dip new capscrews (1) in clean engine oil. Install capscrews and torque evenly to 43 lb-ft (58 

Nm). Tighten capscrews an additional 90 degrees (1/4 turn). 

(11) Rotate crankshaft several revolutions to insure that engine rotates without excessive tightness. 

(12) Measure piston protrusion, refer to paragraph 5.4.5.b(3)(f) and (g). 

(13) Check liners for deep scratches caused by improperly installed or broken piston ring. 

(14) Check side clearance of connecting rods. Connecting rods must have slight side-to-side 

movement. 

(15) Install oil pump and outlet tube, refer to paragraph 5.4.8. 

(16) Install oil pan, refer to paragraph 4.5.3. 

(17) Remove capscrews (1, Figure 5-70) and washers (2) that hold down cylinder liners (3). 

(18) Ensure that all gasket surfaces are clean and free of foreign material. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-83 

(19) Install camshaft followers, refer to paragraph 5.4.1. 

(20) Install cylinder head, refer to paragraph 4.7.4. 

(21) Service coolant and lubrication system, refer to TM 9-6115-672-14. 

5.4.6. CYLINDER LINERS.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Testing Cylinder Liner Height Prior to Removal.

(1) Remove piston, refer to paragraph 5.4.5. 

(2) Check height of each cylinder liner using Dial Indicator. Check height of each cylinder liner at 1, 

5, 7, and 11 o’clock positions as viewed from rear of engine. Record all measurements. 

(3) Compare measurements with specifications given in Table 5-9. Replace any cylinder liner that is 

out of specifications, refer to step b. 

Table 5-9. Cylinder Liner Height Specifications.

Item Specification 

Liner Height Above Block 0.001 - 0.004 in. 

(0.030 – 0.100 mm) 

Maximum Permissible Difference Between 

Readings Within One Cylinder Or Between 

Adjacent Cylinders 

0.002 in. 

(0.05 mm) 

b. Removal.

(1) Remove piston, refer to paragraph 5.4.5. 

(2) Remove capscrews (1, Figure 5-70) and washers (2) securing cylinder liners (3) to cylinder block. 

CAUTION

Stamp cylinder liner on fire dam only. Do not stamp cylinder liner on 

flange. Failure to comply could result in engine damage. 

CAUTION

Stamp piston on side of piston, away from machined surface that contacts 

cylinder liner. Do not stamp top of piston. Failure to comply could result 

in engine damage. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-84 

(3) Number cylinder liners and pistons. Stamp front of cylinder liner to assure correct assembly 

position. 

CAUTION

Keep matched pistons and liners together. Liners must be reinstalled in 

same cylinder bore. Failure to comply could result in excessive engine 

wear. 

(4) Remove cylinder liner (11, Figure 5-72) using Puller. 

(5) Remove O-rings (12) from cylinder block. 

(6) Remove packing (13) from cylinder liner (11). 

(7) Cover all openings to prevent entry of foreign material. 

c. Inspection.

(1) Perform testing of cylinder liner height prior to removal, refer to step a. If out of specifications, 

continue inspection by performing step c (2). 

(2) Remove cylinder liner, refer to step b (4). 

(3) Clean cylinder liner (11, Figure 5-72) as follows: 

(a) Clean cylinder liner using stiff bristle brush. Remove all debris, rust, and scale from 

outer diameter of cylinder liners, under cylinder liner flange, and in O-ring packing areas. 

(b) Visually inspect cylinder liner (11) to insure that there are no nicks or burrs in areas 

where packings will seat. Replace cylinder liner if nicks or burrs are observed. 

CAUTION

Solvents will not remove all abrasives from liner walls. Do not use gasoline, 

kerosene, or commercial solvents to clean liners. Failure to comply could 

result in engine damage. 

(c) Thoroughly clean cylinder liner (11) inner diameter using a solution of 50 percent hot 

water and 50 percent liquid detergent. 

(d) Thoroughly rinse cylinder liner with water and wipe dry with clean rag. 

(e) Swab out cylinder liner (11) as often as necessary with clean SAE 10W oil. Clean 

cylinder liner until a clean, white rag shows no discoloration when rubbed against inner 

diameter of cylinder liner. 

(4) Clean cylinder liner O-ring bore inside cylinder block using O-ring bore cleaning brush IAW 

instructions supplied with O-ring bore cleaning brush. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-85 

(5) Visually inspect cylinder liner (11) as follows: 

(a) Inspect cylinder liner outer diameter (11) for pitting and erosion as follows: 

CAUTION

If liner pitting has occurred, check condition of coolant. 

1 Refer to Figure 5-78. Inspect exterior length of liner for pitting (A). Check 

packing step for erosion (B). If pitting or erosion is observed, measure depth of 

pits with a fine wire or needle. Replace piston liner if depth of any pit is onehalf or more of liner thickness (C) or depth of erosion is one-half or more of the 

packing step (D). 

2 Refer to Table 5-10 for cylinder liner specifications. 

(b) Measure cylinder liner thickness at several points. Refer to Table 5-10 for specifications. 

Replace piston and cylinder liner if out of specifications. 

(c) Measure packing step dimension at several points. Refer to Table 5-10 for specifications. 

(d) Inspect cylinder liner inner diameter for crosshatch honing pattern. Replace piston and 

cylinder liner if crosshatch honing pattern is not visible immediately below top ring turnaround area. 

(e) Inspect cylinder liner inner diameter for pitting or deep vertical scratches that can be 

detected by the fingernail. Replace piston and liner if pitting or deep vertical scratches 

are detected. 

(f) Carefully examine cylinder liner under magnification for signs of fatigue such as fine 

cracks in the flange area and cracks in the ring travel area. Replace piston and cylinder 

liner if signs of fatigue are observed. 

FIGURE 5-78. INSPECTING CYLINDER LINER PITTING 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-86 

(g) Inspect cylinder block for cracks or erosion in the o-ring packing areas. Replace cylinder 

block, refer to paragraph 5.4.7, if cracks or erosion are observed. 

(h) Calculate piston-to-liner clearance as shown below. Replace piston and cylinder liner if 

any clearances exceed specifications. 

1 Position piston (4, Figure 5-72) without rings in matched cylinder liner with 

piston front and cylinder liner front aligned. Move piston down until bottom 

edge of piston skirt is 1.00 in. (25.4 mm) from bottom of cylinder liner. 

2 Use feeler gauge to measure piston skirt-to-cylinder liner clearance 90 degrees 

(1/4 turn) away from piston pin bore. Record measured clearance. Compare 

piston skirt-to-cylinder liner clearance with specifications given in Table 5-11. 

3 Turn piston 90 degrees (1/4 turn) in liner. Measure piston skirt-to-cylinder liner 

clearance 90 degrees (1/4 turn) away from piston pin bore. Record measured 

clearance. 

4 Remove piston from cylinder liner, turn piston upside down, and position piston 

upside down in cylinder liner with piston "front" and cylinder liner "front" 

aligned. 

5 Position piston so bottom edge of piston skirt is 1.00 in. (25.4 mm) below top of 

liner. 

6 Measure piston skirt-to-cylinder liner clearance 90 degrees (1/4 turn) away from 

piston pin bore. Record measured clearance. Compare piston skirt-to-cylinder 

liner clearance with specifications given in Table 5-11. 

7 Turn piston 90 degrees (1/4 turn) in liner. Measure piston skirt-to-cylinder liner 

clearance 90 degrees (1/4 turn) away from piston pin bore. Record measured 

clearance. Compare piston skirt-to-cylinder liner clearance with specifications 

given in Table 5-11. 

8 The difference between clearances in steps 3 and 4 is the amount cylinder liner 

is out-of-round at bottom of cylinder liner. Compare cylinder liner out-of-round 

with specifications given in Table 5-11. 

9 The difference between clearances in steps 6 and 7 is the amount cylinder liner 

is out-of-round at bottom of cylinder liner. Compare cylinder liner out-of-round 

with specifications given in Table 5-11. 

10 The difference between clearances in steps 2 and 6 is the amount cylinder liner 

is tapered. Compare cylinder liner taper with specifications given in Table 5-11. 

(i) Measure cylinder liner flange thickness. Cylinder liner flange thickness should be 0.2371 

- 0.2385 in. (6.022 - 6.058 mm). Replace piston and cylinder liner if cylinder liner flange 

thickness exceeds specifications. 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-87 

Table 5-10. Cylinder Liner Thickness Specifications.

Item Specification 

Cylinder Liner Thickness 0.2313 - 0.2510 in. 

(5.875 - 6.375 mm) 

Packing Step Dimension 0.07947 - 0.09002 in. 

(2.0185 - 2.2865 mm) 

 (j) Measure cylinder liner height above cylinder block as follows: 

1 Ensure that cylinder liner bore in cylinder block and top deck of cylinder block 

are clean. 

2 Install cylinder liner in cylinder liner bore without O-rings and packing. 

3 Ensure that cylinder liner rotates smoothly by hand. If cylinder liner does not 

rotate smoothly by hand, remove cylinder liner and polish cylinder liner bore 

with emery cloth or Brush. Use shop towel or other suitable means to collect 

debris when polishing cylinder liner bore. 

4 Position cylinder liner with liner mark towards front of engine. Secure with 

capscrews and washers, refer to paragraph 5.4.5. Torque capscrews to 50 lb-ft 

(68 Nm). 

5 Using Piston and Liner Height Gauge and Dial Indicator, measure cylinder liner 

height above cylinder block at 1, 5, 7, and 11 o’clock positions as viewed from 

back of engine. Record measurement. Compare cylinder liner height above 

cylinder block with specifications given in Table 5-11. 

Table 5-11. Piston and Cylinder Liner Specifications.

Item Specification 

Piston-to-Liner Clearance (Measured at 

Bottom of Piston Skirt) for Turbocharged 

Engines 

0.003 - 0.006 in. (0.08 - 0.15 mm) 

Maximum Permissible Cylinder Out-ofRound 

0.002 in. (0.05 mm) 

Maximum Permissible Cylinder Taper 0.002 in. (0.05 mm) 

Liner Height Above Block 0.001 - 0.004 in.(0.030 - 0.100 mm) 

Maximum Permissible height differences 

a Nearest Point of Two Adjacent Liners 

or Within A Single Liner 

0.002 in. (0.05 mm) 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

5-88 

Table 5-11. Piston and Cylinder Liner Specifications. – CONT.

Item Specification 

Main Bearing bore in Cylinder Block 3.3250 - 3.3260 in. (84.455 - 84.481 mm) 

Camshaft Follower Bore ID in Block 1.248 - 1.250 in. (31.70 - 31.75 mm) 

Camshaft Follower 1.245 - 1.246 in. (31.61 - 31.64 mm) 

Camshaft Follower-to-Bore Clearance 0.002 - 0.005 in. (0.06 - 0.13 mm) 

NOTE 

Front cam bore in block has a 

replaceable bushing; 

remaining machined bores do 

not have bushings.

Camshaft Bore ID: 

Front (No. 1) in Block (without 

bushing) 

2.3607 - 2.3617 in.( 59.961 - 59.987 mm 

Front (No. 1) in Block (with 

bushing) 

2.2031 - 2.2042 in. (55.961 - 55.987 mm) 

All except No. 1 2.2042 - 2.2052 in. (55.986 - 56.012 mm) 

6 If cylinder liner height above cylinder block is above specification, check 

cylinder block for burrs. Repair or replace as required. 

CAUTION

Only one liner shim may be installed under each cylinder liner flange. 

7 If cylinder liner height is below specifications given in Table 5-11, install liner 

shim or replace as required. 

8 Two shim sizes are available, 0.002 in. (0.05mm) and 0.004 in. (0.10 mm). 

d. Repair.

(1) Deglaze cylinder liner using Flexible Cylinder Hone (D17004BR) and honing oil. 

(2) Use Flexible Cylinder Hone (D17004BR) in accordance with instructions supplied with hone to 

obtain a 45-degree cross-hatch pattern. 

(3) Thoroughly clean cylinder liner after deglazing, refer to step c. above. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

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e. Installation.

CAUTION

Install cylinder liners into same cylinder block bore as removed. DO NOT 

scuff the liner packing across the upper counterbore. 

(1) Remove all covering installed during step b (7). 

CAUTION

If liner outer diameter is pitted or eroded, but still within acceptable service 

limits, rotate liner 90 degrees from its removed position. Pitted sections of 

the liner should be facing the front or rear of the engine. 

(2) Install liner in block bore with mark toward front of engine, unless outer diameter is pitted or 

eroded. 

CAUTION

If you suspect a packing may have sheared or displaced during liner 

installation, remove and examine the liner and packing assembly. If no 

damage is found, check packings for proper position. Resoap packings, and 

reinstall liner assembly. 

(3) A resistance will be felt when the cylinder liner is aligned in pilot bore. Finish seating liners using 

clean, hardwood block and mallet. Gently tap hardwood block over top of cylinder liner with 

mallet. 

NOTE 

Cylinder liner will protrude over top of cylinder block more than normal 

due to uncompressed packings and O-rings. 

(4) Hold liners in place with large flat washers and capscrews. Turn capscrews snug but do not 

tighten. 

(5) Clean cylinder liner bores with waterless hand cleaner after installation. Wipe dry with clean 

towels. 

(6) Apply clean engine oil to liner bores immediately to prevent corrosion. 
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5.4.7. CYLINDER BLOCK.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Disassembly.

(1) If not already performed, mount engine on vehicle engine stand (NSN 4910-01-016-1835 or 

equal). Refer to paragraph 4.10. 

(2) Drain coolant and oil. Refer to TM 9-6115-672-14. 

(3) Remove fan belts. Refer to TM 9-6115-672-14. 

(4) Remove alternator, refer to paragraph 3.9.1. 

(5) Remove turbocharger, refer to paragraph 4.4.1. 

(6) Remove exhaust manifold, refer to paragraph 4.4.3. 

(7) Remove rocker arm cover, refer to paragraph 4.7.1. If option code label is located on rocker arm 

cover, be careful not to damage label. 

(8) Remove water manifold and thermostat housing, refer to paragraph 3.8.2. 

(9) Remove oil cooler piping, refer to paragraph 3.11.3. 

(10) Remove water pump, refer to paragraph 3.8.3. 

(11) Remove dipstick, refer to paragraph 3.11.5. 

(12) Remove oil filter and oil cooler, refer to paragraph 3.11.3. 

(13) Remove oil pressure regulating valve assembly, refer to paragraph 4.5.2. 

(14) Remove fuel filter, refer to paragraph 3.12.2. 

(15) Remove fuel supply pump, refer to paragraph 3.12.3. 

(16) Remove fuel line, refer to paragraph 3.12.4. 

(17) Remove injection lines, refer to paragraph 3.12.4. 

(18) Remove injection pump, refer to paragraph 4.6.1. 

(19) Remove injection nozzles, refer to paragraph 4.6.2. 

(20) Remove starter, refer to paragraph 3.9.2. 
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(21) Remove rocker arm assembly and push rods, refer to paragraph 4.7.3. Keep push rods in order. 

(22) Remove cylinder head, refer to paragraph 4.7.4. 

(23) Remove cam followers, refer to paragraph 4.7.4. 

(24) Remove flywheel, refer to paragraph 4.8.1. 

(25) Remove flywheel housing, refer to paragraph 4.8.3. 

(26) Remove oil pan, refer to paragraph 4.5.3. 

(27) Remove crankshaft pulley, refer to paragraph 4.9.2. 

(28) Remove timing gear cover, refer to paragraph 4.9.3. 

(29) Remove oil pump drive gear, outlet tube and pump body, refer to paragraphs 4.5.4. and 5.4.8. 

(30) Remove timing gears and camshaft, refer to paragraph 5.4.1. 

(31) Remove engine front plate, refer to paragraph 5.4.3. 

(32) Remove oil bypass valve, refer to paragraph 5.4.9. 

(33) Remove pistons and rods, refer to paragraph 5.4.5. Stamp cylinder number on connecting rods. 

(34) Remove crankshaft and main bearings, refer to paragraph 5.4.4. 

(35) Remove cylinder liners, refer to paragraph 5.4.6. Mark each one with cylinder number. 

(36) Remove camshaft bushing, refer to paragraph 5.4.1. 

b. Repair.

(1) Clean cylinder block using the following procedures: 

(a) Remove engine and perform steps listed in paragraph a. to expose cylinder block. 

(b) Remove piston cooling orifices (1), Figure 5-79. 

(c) Remove oil gallery plugs (1), Figure 5-80 using Oil Gallery Plug Tool. 

(d) Remove soft plugs (7,9), Figure 4-46. 

(e) Clean upper and lower liner bores with nylon brush. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Good general ventilation is normally adequate. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

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__________ 

WARNING

Compressed air used for cleaning can create airborne particles that can 

enter the eyes. Pressure will not exceed 30 psi (207 kPa). Eye protection 

required. 

CAUTION

If engine block is cleaned in a hot tank, be sure to remove any aluminum 

parts (such as nameplates). Aluminum parts can be damaged or destroyed 

by hot tank solutions. 

(e) Thoroughly clean engine block using solvent or pressure steam. If necessary, place 

engine block in "hot tank" for total cleaning. Before dipping, ensure any aluminum parts 

such as the engine serial number plate has been removed. 

FIGURE 5-79. INSPECTING PISTON COOLING ORIFICE 

FIGURE 5-80. OIL GALLERY PLUGS 
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(2) After thorough cleaning, inspect and clean cylinder block as follows: 

NOTE 

All components (including piston cooling orifices, soft plugs and oil gallery 

plugs) must be removed from the cylinder block for inspection and 

cleaning. 

(a) Inspect each piston orifice (1, Figure 5-79) to make sure it is not plugged or damaged. 

Cooling orifices deliver approximately 0.4 gallon per min (1.50 liters/min) oil flow. 

(b) Use soft wire brush and compressed air to clean orifice. Replace if condition is 

questionable, refer to paragraph 5.4.7. 

CAUTION

A piston cooling orifice failure could cause damage to piston, piston pins, 

rod pin bushings, and liners. If a piston cooling orifice is left out of 

assembly, low or no oil pressure will result. 

(c) Inspect all passages and crevices to ensure they are cleared of sludge and grease. 

(d) Inspect all coolant passages to ensure they are cleared of any lime deposits and scale. 

CAUTION

Do not file line support flange excessively. Excess filing can damage liner 

support flange and may result in an improper fit. Thoroughly clean all 

filings from cylinder block (2, Figure 5-81). Failure to comply may result in 

engine damage. 

(e) Be sure liner support flange (1, Figure 5-81) is free of any burrs. If burrs are present, use 

a small half-moon file and lightly file (in a circular motion) burr off at approximately 60 

degree angle. Do not let file hit top of cylinder block while filing. 

(f) Carefully inspect cylinder block for cracks or damage. Replace block of there is 

evidence of physical damage. 

(g) When determined that cylinder block is serviceable, clean out threads for cylinder head 

capscrews in top deck of cylinder block using 1/2-13 UNC-2A x 4.00 inches (101.6 mm) 

long tap (3). Use compressed air to remove any debris or fluid which may be present in 

the tapped holes after cleaning. 

(h) Inspect O-ring bore. If required, clean O-ring bore using O-ring bore cleaning brush as 

follows: 

1 Chuck bore cleaning brush in 1/2 inch drill motor. Rotate brush and move in an 

up and down motion in O-ring bore. 

2 Thoroughly clean all lime deposits from O-ring bore. 
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FIGURE 5-81. INSPECTING CYLINDER BLOCK 

(3) Test the cylinder block to confirm that it is within specifications. Perform testing using the 

following steps: 

NOTE 

The cylinder block measurements must be made with the main bearing 

caps installed. 

(a) Before assembly of main bearing caps, identify markings and ensure caps are reinstalled 

in their original position. Refer to paragraph 5.4.4. Install main bearing caps (without 

bearings) in cylinder block and tighten to 100 lb-ft (135 Nm). 

(b) Measure main bearing bore diameter, refer to Figure 5-82. Refer to Table 5-11 for 

specifications. 

(c) Measure engine block main thrust bearing width. Refer to Table 5-5 for specifications. 

(d) If bearing caps are damaged, or bore is not within specifications, replace cylinder block. 
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FIGURE 5-82. MEASURING MAIN BEARING BORE 

NOTE 

Replacement bearing caps are supplied with bearing bore unfinished. 

(e) Measure cam follower bore diameter, refer to Figure 5-83. Refer to Table 5-11 for values 

of the following; camshaft follower bore inner diameter in block, camshaft follower outer 

diameter (new) and camshaft follower-to-bore clearance. 

FIGURE 5-83. MEASURING CAM FOLLOWER BORE DIAMETER 
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(f) Measure camshaft bore diameter, refer to Figure 5-84. Refer to Table 5-11 for 

specifications of the following; camshaft bore inner diameter front No. 1, in block 

without bushing, front No. 1 in block with bushing and all except No. 1. 

FIGURE 5-84. MEASURING CAMSHAFT BORE DIAMETER 

CAUTION

When cylinder block is machined (top deck or crankshaft bearing bores), 

the dimension from centerline of crankshaft bearing bore to top deck will 

be changed. Ensure that this dimension is not less than 13.302 inches 

(337.89 mm). Otherwise, piston may contact cylinder head. 

CAUTION

If cylinder block top deck is resurfaced, also measure depth of liner 

counterbores. Bore depth must be within 0.234 to 0.236 inch (5.95 to 5.99 

mm). 

(g) Measure cylinder block top deck flatness using precision straightedge, refer to Figure 5-

85. New flatness is 0.003 inch (0.08 mm). If flatness is not as specified, resurface engine 

block. 

FIGURE 5-85. MEASURING CYLINDER BLOCK TOP DECK FLATNESS 
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(4) Install plugs and piston cooling orifices in engine block. 

(a) Install all plugs and serial number plate in cylinder block (if removed). 

(b) Install piston cooling orifices; tighten to 8 lb-ft (11 Nm). 

c. Reassembly.

(1) Install cylinder liners without O-rings. Measure liner height, refer to paragraph 5.4.6. 

(2) Install new liners with O-rings, refer to paragraph 5.4.6. 

(3) Install main bearings and crankshaft, refer to paragraph 5.4.4. PLASTIGAGE bearings. 

(4) Install flywheel housing, refer to paragraph 4.8.3. 

(5) Install rear oil seal, refer to paragraph 4.8.2 

(6) Install flywheel, refer to paragraph 4.8.1. 

(7) Install pistons and rods, refer to paragraph 5.4.5. Measure piston protrusion. 

(8) Install oil by-pass valve, refer to paragraph 5.4.9. 

(9) Install front plate, refer to paragraph 5.4.3. 

(10) Install oil outlet tube, O-ring in block, and oil pump, refer to paragraphs 4.5.4. and 5.4.8. 

(11) Install injection pump, refer to paragraph 4.6.1. 

(12) Install camshaft bushing, camshaft, and timing gears, refer to paragraph 5.4.1. 

(13) Time all gears with No. 1 cylinder at TDC compression stroke, refer to paragraph 5.4.1. 

(14) Install timing gear cover and install new front seal, refer to paragraph 4.9.3. 

(15) Install oil pan, refer to paragraph 4.5.3. 

(16) Install oil pressure regulating valve, refer to paragraph 4.5.2. 

(17) Install cam followers in same order as removed, refer to paragraph 4.7.4. 

(18) Install cylinder head gasket, refer to paragraph 4.7.4. 

(19) Install cylinder head (paragraph 4.7.4), push rods, and rocker arm assembly, refer to paragraph 

4.7.3. 

(20) Install starting motor, refer to paragraph 3.9.2. 

(21) Install injection nozzles (with new seals), refer to paragraph 4.6.2. 

(22) Install injection lines, refer to paragraphs 4.6.1. and 3.12.4. 
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(23) Install fuel filter, refer to paragraph 3.12.2. 

(24) Install fuel supply pump, refer to paragraph 3.12.3 

(25) Install fuel lines, refer to paragraph 3.12.4. 

(26) Install oil cooler, refer to paragraph 3.11.3. 

(27) Install new oil filter, and dipstick, refer to paragraph 3.11.5. 

(28) Install water manifold or thermostat housing and thermostats, refer to paragraph 3.8.2. 

(29) Install exhaust manifold, refer to paragraph 4.4.3. 

(30) Install turbocharger, refer to paragraph 4.4.1. Prelube the turbocharger, refer to paragraph 4.4.1. 

(31) Install water pump, refer to paragraph 3.8.3. 

(32) Install hoses, refer to TM 9-6115-672-14. 

(33) Install crankshaft pulley, refer to paragraph 4.9.2. 

(34) Install vibration damper, refer to paragraph 4.9.1. 

(35) Install alternator, refer to paragraph 3.9.1. 

(36) Install fan and fan belts, refer to TM 9-6115-672-14. 

(37) Adjust valves, refer to paragraph 4.7.2. 

(38) Install rocker arm cover, refer to paragraph 4.7.1. 

(39) Install vent tube, refer to TM 9-6115-672-14. 

(40) Fill engine with clean oil and proper coolant, refer to TM 9-6115-672-14. 

(41) Perform engine break-in and standard performance checks, refer to TM 9-6115-672-14. 

5.4.8 OIL PUMP ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 
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a. Removal.

(1) Drain engine lubrication system, refer to TM 9-6115-672-14. 

CAUTION

Oil inlet line is fragile and can become twisted and damaged during 

maintenance. Always use one wrench to hold one fitting stationary while 

the other fitting is loosened or tightened. Failure to comply can cause 

damage to equipment. 

(2) Disconnect turbocharger oil inlet line (3, Figure 4-36) at turbocharger. 

(3) Remove oil pan, refer to paragraph 4.5.3. 

(4) Loosen nut (1, Figure 5-86) several turns until nut covers end of shaft. Using two small pry bars, 

apply force between front plate and gear (2) on two sides of gear. If gear does not loosen, loosen 

capscrews (3, 6, and 10) and strike nut with a small lead hammer while applying force to gear 

until gear loosens. Remove nut and gear. Discard nut. 

(5) Remove capscrews (3), pick-up tube assembly (4) and O-ring seal (5). Discard O-ring seal. 

(6) Remove capscrews (6), cover (7), outlet tube (8), and O-ring seals (9). Discard O-ring seals. 

FIGURE 5-86. OIL PUMP ASSEMBLY 
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(7) Remove capscrew (10) and housing (11). 

(8) Cover all openings to prevent entry of foreign material. 

b. Inspection.

(1) Remove oil pump assembly, refer to step a. 

(2) Remove idler gear (12, Figure 5-86) and drive gear (13) from oil pump housing. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

(3) Clean oil pump parts in cleaning solvent. Dry with compressed air. 

(4) Inspect oil pump components for excessive wear. Replace parts or oil pump assembly as 

necessary. 

(5) Inspect outlet tube (8) and pick-up tube assembly (4) for cracks or defects. Replace parts as 

necessary. 

(6) Install idler gear (12) and drive gear (13). 

(7) Using straight edge and feeler gage, check axial clearance between idler gear (12) and housing 

(11, Figure 5-86), refer to Figure 5-87. Replace oil pump if clearance is not 0.0018 - 0.0065 in. 

(0.045 - 0.165 mm). 

(8) Using straight edge and feeler gage, check axial clearance between drive gear (13) and housing 

(11), refer to Figure 5-87. Replace oil pump if clearance is not 0.0018 - 0.0065 in. (0.045 - 0.165 

mm). 

(9) Using feeler gage, check radial clearance between idler gear (12) and housing (11), refer to Figure 

5-86. Replace oil pump if clearance is not 0.005 - 0.008 in. (0.131 - 0.211 mm). 

(10) Using feeler gage, check radial clearance between drive gear (13) and housing (11), refer to Figure 

5-88. Replace oil pump if clearance is not 0.005 - 0.008 in. (0.131 - 0.211 mm). 

(11) Remove idler gear (12, Figure 5-86). 
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(12) Using inner diameter micrometer, measure idler gear (12) inner diameter. Replace oil pump if 

idler gear inner diameter is not 0.4864 - 0.4867 in. (12.355 - 12.363 mm). 

(13) Using outer diameter micrometer, measure idler gear (12) thickness. Replace oil pump if idler 

gear thickness is not 1.4163 - 1.4183 in. (35.975 - 36.025 mm) 

(14) Using outer diameter micrometer, measure outer diameter of shaft inside housing (11). Replace 

oil pump if shaft outer diameter is not 0.4849 - 0.4855 in. (12.316 - 12.332 mm). 

(15) Remove drive gear (13). 

(16) Using outer diameter micrometer, measure drive gear (13) shaft outer diameter. Replace oil pump 

if drive gear shaft outer diameter is not 0.6306 - 0.6314 in. (16.017 - 16.037 mm). 

(17) Using outer diameter micrometer, measure drive gear (13) thickness. Replace oil pump if drive 

gear thickness is not 1.4163 - 1.4183 in. (35.975 - 36.025 mm) 

(18) Using inner diameter micrometer, measure bushing inner diameter inside housing (11). Replace 

oil pump if bushing inner diameter is not 0.6320 - 0.6339 in. (16.052 - 16.102 mm). 

FIGURE 5-87. OIL PUMP AXIAL CLEARANCE 

FIGURE 5-88. OIL PUMP RADIAL CLEARANCE MEASUREMENT. 
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(19) Inspect cover (7) and housing (11) for evidence of gear rub. Light contact is acceptable. Replace 

oil pump if parts are heavily worn. 

(20) Install idler gear (12) and drive gear (13). 

(21) Install oil pump assembly, refer to step d. 

c. Replacement.

(1) Remove oil pump assembly, refer to step a. 

(2) Inspect oil pump assembly, refer to step b. Replace oil pump components found defective during 

inspection. Replace entire oil pump if components are not within specifications. Refer to step d 

for installation. 

d. Installation.

(1) Remove all covering installed during step a (8). 

(2) Position housing (11, Figure 5-86) on front plate. Install capscrew (10) finger tight. 

(3) Position O-ring seal (9) and outlet tube (8) in cylinder block. 

(4) Position O-ring seal (9) in cover (7). Position cover on housing (11) and outlet tube (8). Install 

capscrews (6) finger tight. 

(5) Position O-ring seal (5) and pick-up tube assembly (4) on cover (7). Install capscrews (3) finger 

tight. 

(6) Torque capscrews (3, and 6) evenly in cross pattern to 26 lb-ft (35 Nm). 

(7) Torque capscrew (10) to 59 lb-ft (80 Nm). 

(8) Position gear (2) on shaft. Install new nut (1) and torque to 37 lb-ft (50 Nm). 

(9) Stake nut (1) to shaft by applying three center punch marks near inner diameter of nut. 

5.4.9 OIL BYPASS VALVE ASSEMBLY.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Removal.

(1) Remove front plate, refer to paragraph 5.4.3. 

(2) Remove oil bypass valve (1, Figure 5-89) and spring (2). 
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(3) Cover all openings to prevent entry of foreign material. 

b. Inspection.

(1) Remove oil bypass valve assembly, refer to step a. 

(2) Inspect oil bypass valve (1, Figure 5-89) for damage. Replace parts as necessary. 

FIGURE 5-89. OIL BYPASS VALVE. 

(3) Inspect spring (2) as follows: 

(a) Inspect spring (2) for damage. 

(b) Using a ruler, check free length of spring (2). Free length of spring should be 2.00 in. (51 

mm). Replace spring if out of specifications. 

(c) Using a spring tester, apply force to spring (2, Figure 5-89) until spring is compressed to 

a length of 1.14 in. (29 mm). Spring tension should be 20 lbs. (87.8 N). Replace spring 

if out of specifications. 

c. Replacement.

(1) Remove oil bypass assembly, refer to step a. 

(2) Inspect oil bypass assembly, refer to step b. Replace oil bypass valve (1, Figure 5-89) or spring 

(2), if found defective. 

(3) Install oil bypass valve assembly, refer to step d. 
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d. Installation.

(1) Remove all covering installed during step a (3). 

(2) Position spring (2, Figure 5-89) and oil bypass valve (1) in cylinder block. 

(3) Install front plate, refer to paragraph 5.4.3. 

5.4.10. CYLINDER HEAD.

NOTE 

The following procedures require complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Disassembly.

(1) Remove cylinder head, refer to paragraph 4.7.4.a. 

__________ 

WARNING

Block cylinder head with a solid block of wood at each end of cylinder head 

while using spring compressor. Failure to comply could result in serious 

personal injury. 

__________ 

WARNING

Do not stand in front of valve spring while compressing valve springs. 

Failure to comply could result in serious personal injury. 

NOTE 

Identify all parts for correct assembly. Use a valve board or other suitable 

means of keeping valves in order. 

(2) Using valve spring compressor, compress valve spring (4, Figure 4-46) and remove valve spring 

retainers (2). 

(3) Release valve spring (4) tension and remove valve rotator (3) and valve spring (4). 

(4) Remove valve (10, 11) from cylinder head. 

(5) Remove valve stem seal (13) from valve guide tower. 
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b. Repair.

NOTE 

The following procedure is provided for repairing the cylinder head. 

Remove cylinder head (refer to paragraph 4.7.4. step a.) and place on a 

suitable workbench. 

(1) Inspect valve springs as follows: 

(a) Inspect valve springs for alignment, wear, and damage. Replace all defective valve 

springs. 

(b) Put valve springs on flat surface to insure that valve springs are square and parallel. 

Replace all defective valve springs. 

(c) Measure valve spring free length. Free length of valve spring should be 2.125 in. (54.4 

mm). Replace valve spring if not within specifications. 

(d) Test valve spring tension with spring compression tester (DO1168AA). Replace valve 

spring if not within specifications. 

1 At 1.81 in. (46.0 mm) height, valve spring tension should be 54 - 62 lb-force 

(240 - 280 N). 

2 At 1.36 in. (34.5 mm) height, valve spring tension should be 133 - 153 lb-force 

(590 - 680 N). 

(2) Inspect valve rotators to insure that valve rotators turn freely in both directions. Replace if 

defective. 

(3) Clean, inspect, and measure valves as follows: 

__________ 

WARNING

When using bench grinder, eye protection must be worn to prevent 

particles from entering eyes. Failure to comply could result in serious eye 

damage or blindness. 

CAUTION

Do not use wire wheel on plated portion of valve stem. Failure to comply 

could result in damage to valve and valve guide. 

(a) Remove all carbon from valve head, face, and unplated portion of valve stem using a soft 

wire wheel on a bench grinder. 

(b) Polish valve stem with steel wool or crocus cloth to remove any scratch marks left by 

wire brush. 
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(c) Clean and inspect valves, valve stems, valve stem tips, and retainer lock groove for 

cracks, wear, or evidence of physical damage. Replace valves that are worn or damaged. 

(d) Measure valve stem outer diameter with outer diameter micrometer. Record 

measurements and compare with valve guide inner diameter, refer to step 4 (i). Replace 

valves not within specifications. 

NOTE 

Intake valve has a larger head outer diameter and is also identified with a 

dimple on valve head. 

1 Intake valve outer diameter should be 0.3096 - 0.3104 in. (7.864 - 7.884 mm). 

2 Exhaust valve outer diameter should be 0.3090 - 0.3100 in. (7.848 - 7.874 mm). 

(e) Use valve inspection center (D-05058ST) to determine if valves are out of round, bent or 

warped. Maximum valve face runout is 0.0015 in. (0.038 mm). Replace valves not 

within specifications. 

CAUTION

Do not nick valve head-to-stem radius while grinding valves. A nick could 

cause valve to break. Break all sharp edges after grinding valve. Failure to 

comply could result in damage to engine. 

(f) Reface valve to 29.25° ± 0.25° using valve refacing station, refer to Figure 5-90. 

(4) Clean, inspect, and measure cylinder head as follows: 

(a) Inspect combustion face for evidence of physical damage, oil or coolant leakage, or 

gasket failure. Repair or replace cylinder head if there is evidence of physical damage; 

such as cracking, abrasion, distortion, or valve seat “torching”. Inspect all cylinder head 

passages for restrictions. 

FIGURE 5-90. VALVE FACE ANGLE 
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(b) Remove all plugs from cylinder head. 

(c) Scrape gasket material, oil, carbon, and rust from cylinder head. Use a powered wire 

brush to clean sealing surfaces. 

__________ 

WARNING

Cleaning solvent is flammable and toxic to eyes, skin, and respiratory tract. 

Skin and eye protection are required. Avoid repeated/prolonged contact. 

Provide adequate ventilation. Failure to comply could result in serious 

injury or death. 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

(d) Clean cylinder head in chemical hot tank if available, or with solvent and brush if hot 

tank is not available. Dry cylinder head with compressed air and blow out all passages. 

(e) Check cylinder head flatness as follows: 

1 Check cylinder head flatness with precision straightedge and feeler gage. Check 

lengthwise, crosswise, and diagonally in several places. 

2 Maximum acceptable out of flat measurements are 0.003 in. (0.08 mm) for 

entire length or width of cylinder head and 0.001 in. (0.03 mm) for every 5.90 

in. (150 mm). 

3 If any measurement exceeds specifications, cylinder head must be resurfaced or 

replaced. To determine if cylinder head can be resurfaced, refer to step 4 (f). 

(Measure cylinder head thickness). 

(f) Measure cylinder head thickness from valve cover gasket rail-to-combustion face using 

outer diameter micrometer. Minimum acceptable cylinder head thickness is 4.104 in. 

(104.24 mm). Replace cylinder head if out of specifications. Refer to Figure 5-91. 

NOTE 

Resurfacing cylinder head is only necessary if cylinder head fails cylinder 

head flatness test, refer to step 4 (e). 
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(g) Resurface cylinder head as follows: 

1 Resurface cylinder head if cylinder head thickness is less than the minimum 

acceptable thickness of 4.104 in. (104.24 mm). Remove only what is necessary 

to restore flatness. 

2 Combustion face surface finish (surface grind only) should be 31 - 125 micro-in. 

(0.7 - 3.2 micrometers). Maximum wave depth is 0.0005 in. (0.012 mm). 

3 Recheck cylinder head flatness, refer to step 4 (e). 

4 Recheck cylinder head thickness, refer to step 4 (f). 

5 Recheck valve recess in cylinder head, refer to paragraph 4.7.4.b. 

FIGURE 5-91. MEASURING CYLINDER HEAD THICKNESS 

__________ 

WARNING

Compressed air used for cleaning can create airborne particles that may 

enter the eyes. Never exceed 30 psi (207 kPa) of pressure. Eye protection 

required. Failure to comply could result in serious eye damage or 

blindness. 

(h) Clean injection nozzle bores with nozzle bore cleaning tool. Blow debris from bore with 

compressed air. 

(i) Clean and measure valve guides as follows: 

1 Clean valve guides with plastic brush and a few drops of light oil or kerosene. 

2 Measure valve guide inner diameter using telescopic gauge and record 

measurements 
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3 Calculate valve guide-to-stem oil clearance by subtracting valve stem outer 

diameter from valve guide inner diameter. Valve guide-to-stem oil clearance 

should be 0.002 - 0.006 in. (0.05 - 0.15 mm). 

4 If valve guide-to-stem oil clearance is out of specifications, knurl, thread, and 

ream valve guides, refer to step 4 (j). 

NOTE 

Valve guides only need to be knurled, threaded, and reamed if valve guideto-stem oil clearance in Step 4(i) (above) is out of specifications. 

(j) Knurl, thread, and ream valve guides as follows: 

1 Knurl valve guides using valve guide knurler kit. Use kit exactly as directed by 

kit manufacturer. 

2 Thread valve guides for entire length of bore using 5/16-24NF modified internal 

thread tap with a major outer diameter of 0.3170 - 0.3199 in. (8.052 - 8.128 

mm). 

3 Hand ream valve guide to finished size to provide valve guide-to-stem oil 

clearance of 0.002 - 0.004 in. (0.05 - 0.10 mm). Valves are available with 0.015 

in. (0.38 mm) and 0.030 in. (0.76 mm) oversize stems. 

(k) Clean and inspect valve seats as follows: 

1 Clean valve seats using electric hand drill with end brush. Remove all carbon 

from valve seats. 

2 Check valve seats for cracks, pits, or excessive wear. Replace valve seats as 

required, refer to Step 7 (m). 

3 Check entire combustion face for rust, scoring, pitting, or cracks. 

NOTE 

Always keep valve guides and work area clean when grinding valve seats. 

(l) Grind valve seats using the following steps: 

1 Select a 0.3125 in. (7.9 mm) pilot that will extend approximately 2.754 in. (6.9 

mm) above valve seat. Wipe pilot stem with oily cloth and insert into valve 

stem guide. 

2 Select an appropriate 30° angle grinding stone which is in good condition and 

install grinding stone on arbor. 

3 Carefully lower grinding stone and arbor on to pilot until grinding stone almost 

contacts valve seat. 
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CAUTION

Support weight of grinder to avoid excessive pressure on grinding stone. 

Failure to comply could result in damage to valve seat. 

CAUTION

Do not grind valve seat too long. Only a few seconds are required to 

recondition the average valve seat. Avoid tendency to grind off too much. 

Do not apply excessive pressure. Failure to comply could result in damage 

to valve seat. 

4 While applying light pressure, carefully grind valve seat with grinding stone. 

5 Remove arbor, grinding stone, and pilot from valve seat. 

CAUTION

If valve seat width is too narrow, valve may burn or erode. Use care when 

narrowing valve seat width. 

6 Check valve seat width with vernier caliper. Valve seat width should be 0.059 - 

0.079 in. (1.50 - 2.00 mm). If valve seat is too wide, reduce width by repeating 

steps 1 through 5 using a 45° grinding stone. 

7 Position new or refaced valve in cylinder head and check contact between valve 

seat and valve face using blue bearing dye. If necessary, lap valve onto valve 

seat using a lapping tool and lapping compound. Replace valves and valve 

inserts as necessary. 

8 Check valve recess in cylinder head, refer to step 4.7.4.(b). 

NOTE 

It is not necessary to replace valve seat inserts if valve seats were 

successfully ground. 

(m) Replace valve seat inserts as follows: 

CAUTION

Do not use oxygen-acetylene torch to remove valve seat inserts. Oxygenacetylene torch will alter the hardness of cylinder head and could cause 

damage to engine. 

1 Raise a burr on bottom of valve seat insert. 

2 Protect surface of cylinder head with cardboard or cloth. 

3 Position chisel with special ground end (Figure 5-92) in burr on valve seat 

insert. Tap handle of chisel with hammer until valve seat insert comes loose. 

Remove and discard valve seat insert. Refer to Figure 5-93 for detailed view. 
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FIGURE 5-92. VALVE SEAT REMOVAL CHISEL 

FIGURE 5-93. REMOVAL OF VALVE SEAT INSERT 

4 Thoroughly clean area around valve seat bore and inspect for damage or cracks. 

Replace cylinder head as necessary. 

5 Measure intake and exhaust valve seat bore in cylinder head, refer to Figure 5-

94 for measurement locations. If bore dimensions are not within specifications 

shown in Table 5-12, machine cylinder head to specifications or replace cylinder 

head. 
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6 Install valve seat inserts in cylinder head using pilot driver and valve seat insert 

installing adapter. Use one end of valve seat insert installing adapter to install 

intake valve seat inserts, the other end is used to install exhaust valve seat 

inserts. 

7 Grind valve seats as required to maintain correct valve recess and valve face-toseat seal, refer to step 4 (l). 

FIGURE 5-94. MEASURE VALVE SEAT BORE IN CYLINDER HEAD 

c. Assembly.

(1) Lubricate stems of valves (10 and 11, Figure 4-46) and valve guides with clean engine oil. 

NOTE 

If valves are reused, install valves in same location from which removed. 

(2) Insert valves (10 and 11) in cylinder head. 

(3) Use valve stem seal installer to slide valve stem seals (13) over stems of valves (10 and 11) and 

onto valve guide tower (3, Figure 5-95). 

(4) Position valve springs (4, Figure 4-46) and rotators (3) on cylinder head. 

(5) Compress valve springs (4, Figure 4-46) using valve spring compressor (JDE138) and install 

retainers on stems of valves (10 and 11). 

(6) Strike end of each valve three or four times using soft, non-metallic mallet to insure proper 

positioning of retainer locks. 

(7) Recheck valve recess, refer to paragraph 4.7.4.(b). 

(8) Test cylinder head prior to installation, refer to paragraph 4.7.4.c. 

(9) Install cylinder head, refer to paragraph 4.7.4.d. 
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Table 5-12. Valve Seat Insert Bore Specifications 

Item Specification 

Exhaust 

 A 1.6924 - 1.6934 in. (42.987 - 43.013 mm) 

 B 0.150 in. (3.82 mm) Reference 

 C 0.3912 - 0.3962 in. (9.936 - 10.064 mm) 

 D 38 - 42° 

 E Maximum Radius 0.019 in. (0.5 mm) 

 Maximum surface finish bore "A" 0.000062 in. (0.00158 mm) 

Intake 

 A 1.8545 - 1.8555 in. (47.104 - 47.130 mm) 

 B 0.136 in. (3.45 mm) Reference 

 C 0.3912 - 0.3962 in. (9.936 - 10.064 mm) 

 D 38 - 42° 

 E Maximum Radius 0.019 in. (0.5 mm) 

 Maximum surface finish bore "A" 0.000062 in. (0.00158 mm) 

Replacement Valve Seat Insert OD: 

 Exhaust 1.8565 - 1.8575 in. (47.155 - 47.181 mm) 

 Intake 1.6944 - 1.6954 in. (43.038 - 43.064 mm) 

FIGURE 5-95. VALVE INSTALLATION 
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5.4.11. OIL PRESSURE REGULATING VALVE ASSEMBLY VALVE SEAT.

NOTE 

The following procedure requires complete access to the engine. If 

necessary, remove engine from generator set, refer to TM 9-6115-672-14. 

Mount engine on repair stand (NSN 4910-01-016-1835 or equal) as outlined 

in paragraph 4.10. 

a. Replacement.

Inspect oil pressure regulating valve assembly, refer to paragraph 4.5.2.b. Replace oil pressure regulating valve 

(4, Figure 4-39) and valve seat (5) if cone of valve is found defective. Refer to the following steps for removal 

and replacement of valve seat (5). 

(1) Remove oil pressure regulating valve, refer to paragraph 4.5.2.a. 

(2) Remove valve seat (5) using collet (JT01727) and slide hammer (JT01718). Discard valve seat. 

CAUTION

Valve seat bore is easily damaged. Do not drive against raised inner rim of 

valve seat. Failure to comply could result in damage to cylinder block. 

(3) Install new valve seat (5) using oil pressure relief valve bushing driver (JD248A) and handle 

(JDG536). Drive valve seat into cylinder block until valve seat bottoms in bore. 

(4) Install oil pressure regulating valve, refer to paragraph 4.5.2.d. 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

A-1 

 APPENDIX A 

 REFERENCES 

A-1 SCOPE.

 This appendix lists all forms, field manuals, technical manuals and miscellaneous publications referenced in 

this manual. 

A-2 FORMS.

 Air Force Reporting Errors Form ........................................................................................AFTO Form 22 

 

 Marine Corps Reporting of Errors Form .............................................................................NAVMC Form 10772 

 Product Quality Deficiency Report......................................................................................SF 368 

 Recommended Changes to DA Publications.......................................................................DA Form 2028-2 

 Recommended Changes to Publications and Blank Forms.................................................DA Form 2028 

 Report of Discrepancy (ROD) .............................................................................................SF 364

 Reporting of Item and Packaging Discrepancies.................................................................AR 735-11-2 

 Reporting of Transportation Discrepancies in Shipment.....................................................AR 55-38 

 Transportation Discrepancy Report.....................................................................................SF 361 

 Equipment Control Records.................................................................................................DA Form 2408-9 

A-3 FIELD MANUALS.

 First Aid for Soldiers............................................................................................................FM 21-11 

A-4 TECHNICAL MANUALS.

 Destruction of Material ........................................................................................................TM 750-244-3 

 Repair Parts and Special Tools List 

 Engine, Diesel Model 6059T (6 Cylinder): 

 Army..............................................................................................................TM9-2815-260-24P 

 Air Force .......................................................................................................TO 38G1-126-2

 Marine Corps.................................................................................................TM 09244A/09245A-24 

 Operator, Unit, Direct Support and General Support Maintenance Manual: 

 Army..............................................................................................................TM9-6115-672-14 

 Air Force .......................................................................................................TO 35C2-3-444-32 

 Marine Corps.................................................................................................TM 09244A/09245A-14 

A-5 MISCELLANEOUS PUBLICATIONS.

 Maintenance Management Policy........................................................................................AFR 66-1 

 Preservation of USAMECOM Mechanical Equipment for Shipment and Storage............TB 740-97-2 

 Stanadyne Service Bulletin ..................................................................................................99689 (8-95) 

 for Model DB4 

 Suggestion Program .............................................................................................................AFR 900-4 

 The Army Maintenance Management System (TAMMS)..................................................DA PAM 738-750 

 USAF Material Deficiency Reporting .................................................................................TO-00-35D54

 John Deere Organization and Maintenance Manual............................................................OMRG25204 

 (20 May 96) 
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A-2 

 John Deere Component Technical Manual..........................................................................CTM 104 (01 June 96) 

 John Deere Parts Catalog (6 Cylinder, 6.8L).......................................................................PC2522 (Oct 96) 
ARMY TM 9-2815-260-24 

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B-1 

MAINTENANCE ALLOCATION CHART

Section I. INTRODUCTION 

B.1 The Army Maintenance System MAC:

 a. This introduction (section I) provides a general explanation of all maintenance and repair functions authorized at 

various maintenance levels under the standard Army Maintenance System concept. 

 b. The Maintenance Allocation Chart (MAC) in section II designates overall authority and responsibility for the 

performance of maintenance functions on the identified end item or component. The application of the 

maintenance functions to the end item or component will be consistent with the capacities and capabilities of the 

designated maintenance levels, which are shown in the MAC in column (4) as: 

 

 Unit - includes two subcolumns, C (operator/crew) and O (unit) maintenance. 

 

 Direct Support - includes an F subcolumn. 

 

 General Support - includes an H subcolumn. 

 

 Depot - includes a D subcolumn. 

 c. Section III lists the tools and test equipment (both special tools and common tool sets) required for each 

maintenance function as referenced from section II. 

 d. Section IV contains supplemental instructions and explanatory notes for a particular maintenance function. 

B.2 Maintenance Functions. Maintenance Functions are limited to and defined as follows: 

 a. Inspect. To determine the serviceability of an item by comparing its physical, mechanical, and/or electrical 

characteristics with established standards through examination (i.e., by sight, sound, or feel). 

 b. Test. To verify serviceability by measuring the mechanical or electrical characteristics of an item and comparing 

those characteristics with prescribed standards. 

 c. Service. Operations required periodically to keep an item in proper operating condition, i.e.; to clean (includes 

decontamination, when required), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical fluids, 

or gases. 

 d. Adjust. To maintain or regulate, within prescribed limits, by bringing into proper position, or by setting the 

operating characteristics to specified parameters. 

 e. Align. To adjust specified variable elements of an item to bring about optimum or desired performance. 

 f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test, measuring, and 

diagnostic equipment used in precision measurement. Consists of comparisons of two instruments, one of which 

is a certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrument 

being compared. 
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B-2

 MAINTENANCE ALLOCATION CHART (Continued) 

 g. Remove/Install. To remove and install the same item when required to perform service or other maintenance 

functions. Install may be the act of emplacing, seating, or fixing into position a spare, repair part, or module 

(component or assembly) in a manner to allow the proper functioning of an equipment or system. 

 h. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. •Replace• is 

authorized by the MAC and assigned maintenance level is shown as the 3rd position code of the SMR code. 

 i. Repair. The application of maintenance services1

 including fault location/troubleshooting2, removal/installation, 

and disassembly/assembly3

 procedures, and maintenance actions4 to identify troubles and restore serviceability to 

an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly, module (component 

or assembly), end item, or system. 

 j. Overhaul. That maintenance effort (service/action) prescribed to restore an item to a completely serviceable/ 

operational condition as required by maintenance standards in appropriate technical publications (i.e., DMWR). 

Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not normally 

return an item to like new condition. 

 k. Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like new 

condition in accordance with original manufacturing standards. Rebuild is the highest degree of material 

maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age 

measurements (e.g. hours/ miles) considered in classifying Army equipment/components. 

B.3 Explanation of Columns in the MAC, Section II. 

 a. Column 1, Group Number. Column 1 lists functional group code numbers, the purpose of which is to identify 

maintenance significant components, assemblies, subassemblies, and modules with the next higher assembly. 

 b. Column 2, Component/Assembly. Column 2 contains the item names of components, assemblies, 

subassemblies, and modules for which maintenance is authorized. 

 

 c. Column 3, Maintenance Function. Column 3 lists the functions to be performed on the item listed in column 2. 

(For detailed explanation of these functions, see paragraph B.2). 

 d. Column 4, Maintenance Level. Column 4 specifies each level of maintenance authorized to perform each 

function listed in Column 3, by indicating work time required (expressed as man-hours in whole hours or 

decimals) in the appropriate subcolumn.. This work-time figure represents the active time required to perform 

that maintenance function at the indicated level of maintenance. If the number or complexity of the tasks within 

the listed maintenance function vary at different maintenance levels, appropriate work time figure will be shown 

for each level. The work-time figure represents the average time required to restore an item (assembly, 

subassembly, component, module, end item, or system) to a serviceable condition under typical field operating 

conditions. This time includes preparation time (condition/follow-on tasks) (including any necessary 

disassembly / assembly time), troubleshooting / fault location time, and quality assurance time in addition to the 

time required to perform the specific 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

B-3/B-4 BLANK 

 MAINTENANCE ALLOCATION CHART (Continued) 

 d.(Cont) tasks identified for the maintenance functions authorized in the MAC. The symbol 

designations for the various maintenance levels are as follows: 

 C Operator or crew maintenance 

 O Unit maintenance 

 F Direct support maintenance 

 H General support maintenance 

 D Depot maintenance 

 e. Column 5, Tools and Test Equipment reference code. Column 5 specifies, by code, those common tool sets (not 

individual tools), common TMDE, and special tools, special TMDE, and support equipment required to perform 

the designated function. Codes are keyed to tools and test equipment in section III. 

 f. Column 6, Remarks. When applicable, this column contains a letter code, in alphabetic order, which shall be 

keyed to the remarks contained in section IV. 

B.4 Explanation of columns in Tool and Test Equipment Requirements, Section III. 

 a. Column 1, Reference Code. The tool and test equipment reference code correlates with a code used in the 

MAC, Section II, Column 5. 

 

 b. Column 2, Maintenance Level. The lowest level of maintenance authorized to use the tool or test equipment. 

 c. Column 3, Nomenclature. Name or identification of the tool or test equipment. 

 d. Column 4, National Stock Number. The National Stock Number of the tool or test equipment. 

 e. Column 5, Tool Number. The manufacturer•s part number, model number, or type number. 

 

B.5 Explanation of Columns in Remarks, Section IV

 a. Column 1, Remarks Code. The code recorded in column 6, section II. 

 b. Column 2, Remarks. This column along with the related codes should be used to clarify maintenance and 

inspection functions by different MOSs involved in maintaining some components. 

ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

B-5 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function UNIT Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

00 ENGINE ASSEMBLY 60KW INSPECT 2.1 1.8 1.1 

 TEST 1.5 7.3 2.8 2,3,5,6,7,8 

 SERVICE .4 

 ADJUST 2.8 1,3,4,6 

 R/I 7.4 56.1 47.0 1,2,3,4,5,6 

 REPLACE 7.4 56.1 47.0 1,2,3,4,5,6 A 

 REPAIR 17.2 39.5 1,2,3,4,5,6,8,41 

01 COOLING SYSTEM INSPECT .8 

 R/I 1.5 1,5 

 REPLACE 1.5 1,5 A 

0101 Thermostat and Water Manifold/Thermostat 

Cover. 

INSPECT 1.1 

 R/I 1.0 1,5 

 REPLACE 1.0 1,5 A 

0102 Water Pump. INSPECT .1 

 R/I 1.5 1,5 

 REPLACE 1.5 1,5 A 

02 ELECTRICAL SYSTEM INSPECT .2 

 TEST 1.0 2.0 2,6,7,8 

 R/I 1.5 5 

 REPLACE 1.5 5 A 

 REPAIR 4.0 4,6,8 

0201 Battery Charging Alternator. INSPECT .1 

 TEST .3 1.0 2,7 

 R/I 1.0 5 

 REPLACE 1.0 5 A 

 REPAIR 2.0 4,8 
ARMY TM 9-2815-260-24 

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B-6 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

0202 Starter. INSPECT .1 

 TEST .5 1.0 6,7,8 

 R/I .5 5 

 REPLACE .5 5 A 

 REPAIR 2.0 6,8 

03 INTAKE AND EXHAUST SYSTEM INSPECT .2 .3 

 TEST 1.0 2,6 

 R/I 7.0 4 

 REPLACE 7.0 4 A 

0301 Turbocharger INSPECT .1 

 TEST 1.0 2,6 

 R/I 2.0 4 

 REPLACE 2.0 4 A 

0302 Intake Manifold. INSPECT .1 .1 

 R/I 2.0 4 

 REPLACE 2.0 4 A 

0303 Exhaust Manifold. INSPECT .1 .1 

 R/I 3.0 4 

 REPLACE 3.0 4 A 

04 LUBRICATION SYSTEM INSPECT .5 .4 

 R/I 1.7 15.5 1,4,5,6 

 REPLACE 1.7 15.5 1,4,5,6 A 

0401 Oil Filter Assembly. INSPECT .1 

 R/I .3 5 

 REPLACE .3 5 A 

 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

B-7 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

0402 Oil Cooler. INSPECT .1 

 R/I 1.0 1,5 

 REPLACE 1.0 1,5 A 

0403 Oil Pressure Regulating Valve Assembly. INSPECT .1 

 R/I 1.0 4 

 REPLACE 1.0 4 A 

0405 Oil Pump Assembly. INSPECT .1 

 R/I 8.5 6 

 REPLACE 8.5 6 A 

0406 Oil Bypass Valve Assembly. INSPECT .1 

 R/I 10.0 6 

 REPLACE 10.0 6 A 

0407 Oil Fill Tube. INSPECT .1 

 R/I .2 5 

 REPLACE .2 5 A 

0408 Oil Dipstick Tube. INSPECT .1 

 R/I .2 1,5 

 REPLACE .2 1,5 A 

0409 Oil Pan. INSPECT .1 .1 

 R/I 8.0 4 

 REPLACE 8.0 4 A 

05 FUEL SYSTEM INSPECT .4 .1 

 SERVICE .4 5 

 TEST .5 2.0 2,5,6 

 R/I 2.7 4.7 1,2,5,6 

 REPLACE 2.7 4.7 1,2,5,6 A 

 REPAIR .2 4.5 2,6,41 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

B-8 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

0501 Fuel Filter. SERVICE .4 5 

 R/I .2 .2 5 

 REPLACE .2 5 A 

 REPAIR .2 5 

0502 Fuel Transfer Supply Pump. INSPECT .1 

 TEST .5 5 

 R/I 1.0 1,5 

 REPLACE 1.0 1,5 A 

0503 Fuel Lines. INSPECT .1 

 R/I 1.5 5 

 REPLACE 1.5 5 A 

0504 Fuel Injection Pump. INSPECT .1 .1 

 TEST 1.0 2,6 

 R/I 2.0 6 

 REPLACE 2.0 6 A 

 REPAIR 16.0 2,6,41 

0505 Fuel Injection Nozzle Assembly. INSPECT .1 

 TEST 1.0 2,6 

 R/I 1.5 2,6 

 REPLACE 1.5 2,6 A 

06 CYLINDER HEAD ASSEMBLY ADJUST 2.8 3,4,6 

 TEST 2.3 3,6 

 R/I 7.4 3,4,5,6 

 REPLACE 7.4 3,4,5,6 A 

 REPAIR 7.0 3,4,6 

 
ARMY TM 9-2815-260-24 

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MARINE CORPS TM 09244A/09245A-24

B-9 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

0601 Rocker Arm Cover. R/I .4 5 

 REPLACE .4 5 A 

0602 Intake and Exhaust Valves TEST 1.0 3,6 

 ADJUST 2.4 3,6 

0603 Rocker Arm Assembly R/I 2.5 4 

 REPLACE 2.5 4 A 

 ADJUST .8 3,4 

 REPAIR 2.5 4 

0604 Cylinder Head. TEST 1.5 3,6 

 R/I 4.5 3,6 

 REPLACE 4.5 3,6 A 

 REPAIR 4.5 3,6 

07 FLYWHEEL AND HOUSING ASSEMBLY INSPECT .7 

 R/I 17.5 3,6 

 REPLACE 17.5 3,6 A 

 REPAIR 6.0 3,6 

0701 Flywheel. INSPECT .1 

 R/I 9.0 3,6 

 REPLACE 9.0 3,6 A 

0702 Rear Crankshaft Oil Seal/Wear Sleeve 

Assembly. 

INSPECT .1 

 R/I 10.0 3,6 

 REPLACE 10.0 3,6 A 

0703 Flywheel Housing. INSPECT .5 

 R/I 10.0 3,6 

 REPLACE 10.0 3,6 A 

 
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B-10 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

08 TORSIONAL DAMPER INSPECT .1 

 R/I 1.0 6 

 REPLACE 1.0 6 A 

09 Crankshaft Pulley. INSPECT .1 

 R/I 1.0 6 

 REPLACE 1.0 6 A 

10 Timing Gear Cover. INSPECT .1 

 R/I 10.0 3,6 

 REPLACE 10.0 3,6 A 

11 SHORT BLOCK ASSEMBLY INSPECT 1.1 

 TEST 2.8 2,3,6 

 R/I 47.0 2,3,6 

 REPLACE 47.0 2,3,6 A 

 REPAIR 35.0 2,3,6 

1101 Camshaft Assembly. INSPECT .2 

 TEST .5 3,6 

 R/I 10.0 3,6 

 REPLACE 10.0 3,6 A 

1102 Idler Gears and Idler Gear Shafts. TEST .5 2,3,6 

 R/I 10.0 3,6 

1103 Front Plate. INSPECT .3 

 R/I 9.5 2,3,6 

 
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B-11 

SECTION II. MAINTENANCE ALLOCATION CHART FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

(1) (2) (3) (4) 

Maintenance Level 

(5) (6) 

Number Component/Assembly Function Unit Direct 

Support 

General Depot Ref Code Code 

 C O F H D 

1104 Crankshaft and Main Bearings. INSPECT .4 

 TEST 1.4 2,3,6 

 R/I 17.0 3,6 

 REPAIR 11.0 2,3,6 

1105 Pistons and Connecting Rods. R/I 16.0 3,6 

 REPAIR 7.0 3,6 

1106 Cylinder Liner. INSPECT .2 

 TEST 1.0 6 

 R/I 16.0 6 

 REPAIR 5.0 2,3,6 

1107 Cylinder Block REPAIR 15.0 3,6 
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B-12 

Section III. TOOL AND TEST EQUIPMENT REQUIREMENTS FOR 

DIESEL ENGINE MODEL 6068TF151

TOOL OR TEST 

EQUIPMENT REF 

CODE 

MAINTENANCE 

LEVEL 

NOMENCLATURE NATIONAL STOCK 

NUMBER 

TOOL NUMBER 

1 O SHOP EQUIPMENT, 

AUTOMOTIVE MAINT AND 

REPAIR., ORGANIZATIONAL 

MAINTENANCE COMMON 

NO. 1, LESS POWER 

4910-00-754-0654 SC 4910-95-A74 

(10 Sept. 1994) 

2 F SHOP EQUIPMENT, FUEL AND 

ELECTRICAL SYSTEM 

ENGINE FIELD 

MAINTENANCE, BASIC, LESS 

POWER 

4910-00-754-0714 SC 4910-95-CL-B20 

(01 June 1987) 

3 F SHOP EQUIPMENT, 

AUTOMOTIVE, 

MAINTENANCE AND REPAIR, 

FIELD MAINTENANCE, 

SUPPLEMENTAL SET NO. 2, 

LESS POWER 

4910-00-754-0707 SC 4910-95-A63 

(01 December 1987) 

4 F SHOP EQUIPMENT, 

AUTOMOTIVE 

MAINTENANCE AND REPAIR: 

FIELD MAINTENANCE , 

BASIC, LESS POWER 

4910-00-754-0705 SC 4910-95-A31 

(30 June 1990) 

5 O TOOL KIT, GENERAL 

MECHANIC•S: AUTOMOTIVE 

5180-00-177-7033 SC 5180-95-N26 

(30 October 1986) 

6 F SHOP EQUIPMENT, 

AUTOMOTIVE 

MAINTENANCE AND REPAIR: 

FIELD MAINTENANCE, 

WHEELED VEHICLES, POST, 

CAMP, AND STATION SET A 

4910-00-348-7696 SC 4910-95-A02 

(1 October 1989) 

7 O MULTIMETER 6625-01-312-2930 FLUKE Model 87 

8 F SHOP EQUIPMENT, 

ELECTRICAL REPAIR, 

SEMITRAILER MOUNTED 

4940-00-294-9517 SC 4940-95-B05 

9 F OIL PRESSURE RELIEF 

VALVE BUSHING DRIVER 

5120-01-393-3638 JOHN DEERE 

JD248A 

10 F HANDLE, BUSHING DRIVER 5120-01-391-2093 JOHN DEERE 

JDG536 

11 F FLYWHEEL TURNING TOOL (NONE) JOHN DEERE 

JDG820 
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B-13 

Section III. TOOL AND TEST EQUIPMENT REQUIREMENTS FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

TOOL OR TEST 

EQUIPMENT REF 

CODE 

MAINTENANCE 

LEVEL 

NOMENCLATURE NATIONAL STOCK 

NUMBER 

TOOL NUMBER 

12 F TIMING PIN 5135-01-321-6068 JOHN DEERE 

JDE81-4 

13 F INJECTION PUMP TIMING 

GEAR PULLER 

5120-01-393-9501 JOHN DEERE 

JDG670A 

14 F VALVE GUIDE KNURLER KIT (NONE) JOHN DEERE 

JTO5949 

15 F VALVE SEAT PILOT DRIVER 5120-01-393-1254 JOHN DEERE 

JDG676 

16 F VALVE SEAT INSERT 

INSTALLING ADAPTER 

5120-01-393-3892 JOHN DEERE 

JDG675 

17 F VALVE STEM SEAL 

INSTALLER 

(NONE) JOHN DEERE 

JDG678 

18 H PISTON AND CYLINDER 

LINER HEIGHT GAUGE 

5210-01-351-5114 JOHN DEERE 

JDG451 

19 F SEAL AND WEAR SLEEVE 

REMOVER 

(NONE) JOHN DEERE 

JDG698A 

20 F SEAL AND WEAR SLEEVE 

INSTALLER SET 

5120-01-384-4147 JOHN DEERE 

JT30040 

21 F CAMSHAFT GEAR AND 

FRONT OIL SEAL 

INSTALLER SET 

(NONE) JOHN DEERE 

JDG954 

22 H CAMSHAFT BUSHING 

SERVICE SET 

(NONE) JOHN DEERE 

JDG739B 

23 H IDLER GEAR BUSHING 

DRIVER 

5120-01-394-5256 JOHN DEERE 

JD252 

24 H IDLER GEAR BUSHING 

DRIVER HANDLE 

5120-00-034-0881 JOHN DEERE 

10914188 

25 H GEAR TIMING TOOL 5120-01-353-1121 JOHN DEERE 

JD254A 

26 H OIL GALLERY PLUG TOOL (NONE) JOHN DEERE 

JDG782 

27 H RING GROOVE WEAR 

GAUGE 

(NONE) JOHN DEERE 

JDE62 

 
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B-14 

Section III. TOOL AND TEST EQUIPMENT REQUIREMENTS FOR 

DIESEL ENGINE MODEL 6068TF151 – CONT.

TOOL OR TEST 

EQUIPMENT REF 

CODE 

MAINTENANCE 

LEVEL 

NOMENCLATURE NATIONAL STOCK 

NUMBER 

TOOL NUMBER 

28 H PISTON PIN BUSHING 

REMOVER AND 

INSTALLER (SMALL) 

(NONE) JOHN DEERE 

JDE88 

29 H CYLINDER LINER PULLER 5120-01-346-0983 JOHN DEERE 

D01073AA 

30 O ADAPTER 4910-01-394-6187 JOHN DEERE 

JT01679 

31 O HOLDING CLAMP 4910-01-395-3445 JOHN DEERE 

JT02017 

32 O TEST GAUGE 6620-01-382-7334 JOHN DEERE 

JT01682 

33 O SLIDE HAMMER (NONE) JOHN DEERE 

D01299AA 

34 O DIPSTICK DRIVER (NONE) JOHN DEERE 

JDG965 

35 F COLLET (NONE) JOHN DEERE 

JT01727 

36 F SLIDE HAMMER (NONE) JOHN DEERE 

JT01718 

37 H PISTON RING 

COMPRESSOR 

5120-01-351-3471 JOHN DEERE 

JDE84 

38 F VALVE INSPECTION 

CENTER 

(NONE) JOHN DEERE 

D-05058ST 

39 F NOZZLE BORE CLEANING 

TOOL 

(NONE) JOHN DEERE 

JDE39 

40 F TRANSFER PUMP 

PRESSURE ADJUSTER 

(NONE) STANADYNE 

26079 

41 F STANADYNE SERVICE 

TOOL KIT 

(NONE) STANADYNE 

18951 
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B-15 

Section III. TOOLS CONTAINED IN STANADYNE SERVICE 

TOOL KIT 18951 (Continued)

TOOL OR TEST 

EQUIPMENT 

REF CODE 

MAINTENANCE 

LEVEL 

NOMENCLATURE NATIONAL 

STOCK NUMBER 

TOOL 

NUMBER 

1 H VALVE EXTRACTOR (NONE) 26081 

2 H DIMENSION SETTING 

FIXTURE 

5120-00-200-4526 19969 

3 H GAGE, LINKAGE KIT (NONE) 23093 

4 H WRENCH, END CAP 5120-01-207-5563 20548 

 H TIMING LINE INDICATOR 5120-01-394-2315 20395 

6 H SHUTOFF CAM REMOVER (NONE) 20992 

7 H ADVANCE PLUG WRENCH (NONE) 14490 

8 H SMALL SNAP RING PLIERS (NONE) 13337 

9 H SNAP RING PLIERSSQUEEZE TO CLOSE 

(NONE) 20043 

10 H SNAP RING PLIERSSQUEEZE TO OPEN 

(NONE) 20044 

11 H BRASS HOOK (NONE) 13301 

12 H ROTOR SUPPORT TOOL (NONE) 16313 

13 H LINKAGE HOOK WRENCH (NONE) 13379 

14 H ADVANCE PISTON RING 

COMPRESSOR 

(NONE) 16199 

15 H ADVANCE PLUG SOCKET (NONE) 27760 

16 H ADVANCE PLUG SOCKET (NONE) 27761 

17 F TRANSFER PUMP 

PRESSURE TAP 

4910-01-395-4246 21900 

18 F ADVANCE INDICATOR 5120-01-249-0368 23745 

19 F NOZZLE CLEANING KIT 5180-01-351-3467 16494 

20 H BEARING AND SEAL 

REMOVER 

5120-01-351-3953 28311 

21 H BEARING AND SEAL 

INSTALLATION TOOL 

5120-01-351-3955 28316 
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B-16 

Section III. TOOLS CONTAINED IN STANADYNE SERVICE 

TOOL KIT 18951 (Continued)

TOOL OR TEST 

EQUIPMENT 

REF CODE 

MAINTENANCE 

LEVEL 

NOMENCLATURE NATIONAL 

STOCK NUMBER 

TOOL 

NUMBER 

22 H ROTOR SUPPORT TOOL (NONE) 16313 

Section IV. REMARKS 

FOR 

DIESEL ENGINE MODEL 6068TF151 

REMARKS 

CODE 

REMARKS 

A Replace function identical to removal/install function 
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C-1 

APPENDIX C 

 COMPONENTS OF END ITEM (COEI) AND BASIC ISSUE ITEMS (BII) LIST 

 SECTION I. INTRODUCTION 

C-1 SCOPE.

 This appendix lists components of the end item and basic issue items for the generator set to help 

inventory the items for safe and efficient operation of the equipment. 

C-2 GENERAL.

 The Components of End Item (COEI) and Basic Issue Items (BII) lists are divided into the 

following sections: 

 a. Section II, Components of End Item. This listing is for information purposes only, and is 

not authority to requisition replacements. These items are part of the generator set. As 

part of the end item, these items must be with the end item whenever it is issued or 

transferred between property accounts. Items of COEI are removed and separately 

packaged for transportation or shipment only when necessary. Illustrations are furnished 

to help you find and identify the items. 

 b. Section III. Basic Issue Items. These essential items are required to place the generator 

set in operation, operate it, and to do emergency repairs. Although shipped separately 

packaged, BII must be with the generator set during operation and when it is transferred 

between property accounts. This list is your authority to request/requisition them for 

replacement based on authorization of the end item by the TOE/MTOE. Illustrations are 

furnished to help you find and identify the items. 

C-3 EXPLANATION OF COLUMNS.

 The following provides an explanation of columns found in the tabular listing: 

 a. Column (1), Illus Number, gives the identifying number of the item illustrated. 

 b. Column (2), National Stock Number, identifies the stock number of the item to be used for 

requisitioning purposes. 

 c. Column (3), Description and Usable On Code, identifies the Federal item name (in all 

capital letters) followed by a minimal description when needed. The last line below the 

description is the Commercial and Government Entity Code (CAGEC) in parentheses and 

the part number. 

 d. Column (4), U/I (unit of issue), indicates how the item is issued for the National Stock 

Number shown in column (2). 

 e. Column (5), Qty Rqd, indicates the quantity required. 
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C-2 

 SECTION II. COMPONENTS OF END ITEM 

 NONE 

SECTION III. BASIC ISSUE ITEMS 

 (1) 

 Illus 

 Number 

 (2) 

 National Stock 

 Number 

 (3) 

 Description 

 Cage and Part Number 

 Usable 

 On Code 

 (4) 

 U/I 

 (5) 

 Qty 

 Reqd 

 1 TECHNICAL MANUAL 

 TM 9-2815-260-24 

 EA 

 

 1 

 2 WARRANTY TECHNICAL 

BULLETIN 

 TO BE ASSIGNED 

 EA 1 
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C-3/C-4 BLANK 

1. TECHNICAL MANUAL 

2. WARRANTY TECHNICAL BULLETIN 

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D-1/D-2 BLANK 

 APPENDIX D 

 ADDITIONAL AUTHORIZATION LIST (AAL) 

 REFER TO END ITEM MAINTENANCE MANUAL APPENDIX D

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E-1 

APPENDIX E 

 EXPENDABLE AND DURABLE ITEMS LIST 

 SECTION I. INTRODUCTION 

E-1 SCOPE.

 This appendix lists expendable supplies and materials required to operate and maintain the 

generator set. These items are authorized by CTA 50-970, Expendable Items (except medical, 

Class V, repair parts, and heraldic items). 

E-2 EXPLANATION OF COLUMNS.

 a. Column (1) - Item Number. Number assigned to an entry in the listing for reference within 

the technical manual to identify the material, i.e. "Use of cleaning compound (Item 5, 

Appendix E)." 

 b. Column (2) - Level. Identifies the lowest level of maintenance requiring the listed item. 

 c. Column (3) - National Stock Number (NSN). Standardized number assigned to an item for 

the purpose of requisition. 

 d. Column (4) - Description. Federal item name and, if required, description of the item. 

The last line for each applicable item indicates the Commercial and Government (CAGE) 

code in parenthesis followed by the part number. 

 e. Column (5) - Unit of Measure (U/M). Measure used in performing actual maintenance 

function. Measure is expressed by a two character alphabetical abbreviation (i.e., ea, in, 

pr). If the unit of measure differs from the unit of issue, requisition the lowest unit that 

will satisfy requirements. 

 SECTION II. EXPENDABLE AND DURABLE ITEMS LIST

EXPENDABLE DURABLE ITEMS LIST 

 (1) 

 Item 

 Number 

 (2) 

 Level 

 (3) 

 National Stock 

 Number 

 (4) 

 Description 

 (5) 

 U/M 

 1 O, F 8400-00-390-7959 Adhesive, Seal, EC847 QT 

 2 O, F 6850-00-181-7929 Antifreeze, MIL-A-46153, 1 Gal. Can GL 

 3 O, F 6850-00-181-7933 Antifreeze, MIL-A-46153, 5 Gal. Can GL 

 4 O, F 6850-00-181-7940 Antifreeze, MIL-S-46153, 55 Gal. Can GL 
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E-2 

EXPENDABLE DURABLE ITEMS LIST - CONT. 

 (1) 

 Item 

 Number 

 (2) 

 Level 

 (3) 

 National Stock 

 Number 

 (4) 

 Description 

 (5) 

 U/M 

 5 O, F 6850-00-174-1806 Antifreeze, MIL-A-11755, 1 Gal. Can GL 

 6 O, F 8030-01-234-2792 Antiseize Compound, CP-8, 8 Oz. Can OZ 

 7 O 2910-00-646-9727 Cartridge, Engine, Ether, MS39254 EA 

 8 O, F 7920-01-338-3329 Cloth, Cleaning, TX-1250 EA 

 9 F 8030-00-056-8673 Compound, Thermo, Pentrox A OZ 

 10 O, F 9150-00-663-1770 Grease, General Purpose, 630AA, 6 Lb. Can LB 

 11 O, F 6850-01-160-3868 Inhibitor, Corrosion, MIL-A-53009 QT 

 12 O, F 9150-00-152-4117 Lubricating Oil, Engine, MIL-L-2104, 15/40W QT 

 13 O, F 9150-00-189-6727 Lubricating Oil, Engine, BRAYC0421C, 10W QT 

 14 O, F 9150-00-186-6681 Lubricating Oil, Engine, ALIEDC030, 30W QT 

 15 O, F 9150-00-402-2372 Lubricating Oil, Engine, MIL-L-46167, OEA QT 

 16 O, F 5330-00-543-3600 Paper, Abrasive, ALOXGRIT 80 SH 

 17 O, F 8030-01-408-9944 Seal, Edge, PES-821-B QT 

 18 O, F 8040-00-843-0802 Sealant, RTV108 OZ 

 19 O, F 6850-00-264-9038 Solvent, Dry Cleaning, P-D-680, 5 Gal. Can GL 

 20 O, F 8030-00-849-0071 Sealing Compound, FORM GASKET 2 TU 

 21 O, F 8040-01-359-8441 Sealing Compound, MIL-S-22473, Grade HW OZ 

22 F Sealant, Locktite 242 OZ 

23 F Sealant, Locktite 680 OZ 

24 F Sealant, Locktite 575 OZ 

25 F Form-in-Place Gasket, Locktite TY6304 OZ 

26 F Grease Kit, 1859 EA 

27 F Grease, 30465 LB 

28 F Lubricant, 22204 OZ 

29 F Grease, Hi-Temp, TY6333 LB 
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F-1 

APPENDIX F 

 ILLUSTRATED LIST OF MANUFACTURED ITEMS 

G.1 INTRODUCTION.

 This appendix includes complete instructions for fabricating or assembling parts as required for 

the engine. 

 NOTE 

 All dimensions are expressed in inches. Refer to Table F-1 for metric conversion. 

Figure Number 

 Page 

F-1 Fuel Injection Pump Holding Fixture............................................................................... F-2 

F-2 Fuel Injection Pump Timing Mark Template................................................................... F-3 
ARMY TM 9-2815-260-24 

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F-2 

 

FIGURE F-1, FUEL INJECTION PUMP HOLDING FIXTURE 
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F-3 

FIGURE F-2, FUEL INJECTION PUMP TIMING MARK TEMPLATE 
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F-4 

TABLE F-1. METRIC CONVERSION 

Part I. Fractional Equivalent 

Fractional Inches Decimal Inches mm 

1/16 .0625 1.587 

1/8 .1250 3.175 

3/16 .1875 4.762 

1/4 .2500 6.350 

5/16 .3125 7.937 

3/8 .3750 9.525 

7/16 .4375 11.112 

1/2 .5000 12.700 

9/16 .5625 14.287 

5/8 .6250 15.875 

11/16 .6875 17.462 

3/4 .7500 19.050 

13/16 .8125 20.637 

7/8 .8750 22.225 

15/16 .9375 23.812 

1 1 25.400 

Part II. Inches to Centimeters 

Inches cm 

1 2.540 

2 5.080 

3 7.620 

4 10.160 

5 12.700 

6 15.240 

7 17.780 

8 20.320 

9 22.860 

10 25.400 

20 50.800 

30 76.200 

40 101.600 

50 127.000 

60 152.400 

70 177.800 

80 203.200 

90 228.600 

100 254.000 
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G-1 

 APPENDIX G 

 TORQUE LIMITS 

SECTION I. INTRODUCTION 

G.1 SCOPE. 

 Section II lists torque ratings for fasteners used on the engine. When specific torque values called 

out in the maintenance procedures, they supersede the values in this appendix. Table G-1 lists 

torque limits for standard fasteners installed dry. Table G-2 provides formulas for converting the 

dry torque values to wet. Table G-3 lists torque limits for metric fasteners installed dry. 

 SECTION II. TORQUE LIMITS 

 TABLE G-1. TORQUE LIMITS FOR DRY FASTENERS

 

SIZE TORQUE 

SAE GRADE 0-1-2 SAE GRADE 3 SAE GRADE 5 

Diameter in 

Inches 

Threads Per 

Inch 

Millimeters Foot 

Pounds 

Newton 

Meters 

Foot 

Pounds 

Newton 

Meters 

Foot 

Pounds 

Newton 

Meters 

1/4 20 6.350 6 8 9 12 10 14 

1/4 28 6.350 7 9 10 13 11 15 

5/16 18 7.937 12 16 17 23 19 26 

5/16 24 7.937 13 18 18 25 21 28 

3/8 16 9.525 20 27 30 40 33 45 

3/8 24 9.525 22 30 33 44 36 49 

7/16 14 11.112 32 43 47 64 54 73 

7/16 20 11.112 35 47 51 69 59 80 

1/2 13 12.700 47 64 69 93 78 106 

1/2 20 12.700 51 69 75 102 85 115 

9/16 12 14.287 69 94 103 140 114 155 

9/16 18 14.287 75 102 112 152 124 168 

5/8 11 15.875 96 130 145 197 154 209 

5/8 28 15.875 105 142 158 214 168 228 

3/4 10 19.050 155 210 234 317 257 348 

3/4 26 19.050 169 229 255 346 280 380 

7/8 9 22.225 206 279 372 504 382 518 

7/8 24 22.225 225 304 405 550 416 565 

1 8 25.400 310 420 551 747 587 796 

1 14 25.400 338 458 601 814 640 867 
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G-2 

TABLE G-1. TORQUE LIMITS FOR DRY FASTENERS (continued) 

 

SIZE TORQUE 

SAE GRADE 6 SAE GRADE 7 SAE GRADE 8 

Diameter in 

Inches 

Threads Per 

Inch 

Millimeters Foot 

Pounds 

Newton 

Meters 

Foot 

Pounds 

Newton 

Meters 

Foot 

Pounds 

Newton 

Meters 

1/4 20 6.350 13 17 13 18 14 19 

1/4 28 6.350 14 18 14 19 15 21 

5/16 18 7.937 24 33 25 34 29 39 

5/16 24 7.937 26 35 27 37 32 43 

3/8 16 9.525 43 58 44 60 47 64 

3/8 24 9.525 47 64 48 65 51 69 

7/16 14 11.112 69 94 71 96 78 106 

7/16 20 11.112 75 102 77 105 85 115 

1/2 13 12.700 106 144 110 149 119 161 

1/2 20 12.700 116 157 120 163 130 176 

9/16 12 14.287 150 203 154 209 169 229 

9/16 18 14.287 164 222 168 228 184 250 

5/8 11 15.875 209 283 215 291 230 312 

5/8 28 15.875 228 309 234 318 251 340 

3/4 10 19.050 350 475 360 488 380 515 

3/4 26 19.050 382 517 392 532 414 562 

7/8 9 22.225 550 746 570 773 600 813 

7/8 24 22.225 600 813 621 842 654 887 

1 8 25.400 825 1119 840 1139 900 1220 

1 14 25.400 899 1219 916 1241 981 1330 

See Table G-2 for the effect of lubrication on torque. 

TABLE G-2. EFFECT OF LUBRICATION ON TORQUE 

 TORQUE RATING IN FOOT-POUNDS 

Lubricant 5/16-18 Thread/Inch 1/2-13 Thread/Inch 

NO LUBE, Steel 29 121 

Plated and cleaned 19 (66%) 90 (26%) 

SAE 20 Oil 18 (38%) 87 (28%) 

SAE 40 Oil 17 (41%) 83 (31%) 

Plated and SAE 30 16 (45%) 79 (35%) 

White Grease 16 (45%) 79 (35%) 

White Moly Film 14 (52%) 66 (45%) 

Graphite and Oil 13 (55%) 62 (49%) 

Use the above lubrication percentages to calculate the approximate decrease in torque rating for other bolt sizes. 
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G-3/G-4 BLANK 

TABLE G-3. TORQUE LIMITS FOR DRY FASTENERS (METRIC) 

 

 Standard 5D Standard 8G Standard 10K Standard 12K 

Diameter in 

Millimeters 

Coarse 

Thread Pitch 

Inches Ft-lb Nm Ft-lb Nm Ft-lb Nm Ft-lb Nm 

6 1.00 0.2362 5 7 6 8 8 11 10 14 

8 1.00 0.3150 10 14 16 22 22 30 27 37 

10 1.25 0.3937 19 26 31 42 40 54 49 66 

12 1.25 0.4624 34 46 54 73 70 95 86 117 

14 1.25 0.5512 55 75 89 121 117 159 137 186 

16 2.00 0.6299 83 113 132 179 175 237 208 282 

18 2.00 0.7087 111 150 182 247 236 320 283 384 

22 2.50 0.8771 182 247 284 385 394 534 464 629 

24 3.00 0.9449 261 354 419 568 570 773 689 934 

To determine torque rating for a fine thread bolt, increase the above coarse thread ratings by 9%. See Table G-2 for 

the effect of lubrication on torque. 

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H-1 

APPENDIX H 

 MANDATORY REPLACEMENT PARTS 

 SECTION I. INTRODUCTION 

H.1 SCOPE. Section II of this appendix list parts that must be replaced if removed during 

maintenance. 

 SECTION II. MANDATORY REPLACEMENT PARTS 

 TABLE H-1. MANDATORY REPLACEMENT PARTS 

PART NO. PART NAME QTY. REMARKS 

R123501 GASKET 1 ENGINE OIL COOLER 

R123572 GASKET 1 TURBOCHARGER 

R123295 GASKET 1 ENGINE FRONT PLATE 

R123504 GASKET 1 OIL FILTER 

R123502 GASKET 1 ENGINE OIL COOLER 

R123504 GASKET 1 ENGINE W/FILTER 

R18275 GASKET 1 AIR INLET 

T43514 GASKET 1 (PLASTIC GASKET) CYLINDER BLOCK 

R90658 GASKET 6 EXHAUST MANIFOLD 

R123354 GASKET 1 ENGINE OIL PAN 

R136516 GASKET 1 (SUB FOR R123421 AND R134534) TIMING GEAR COVER 

R123417 GASKET 1 WATER PUMP 

R136495 GASKET 2 (SUB FOR R116297) ENGINE OIL FILLER NECK 

R27149 O-RING 1 FLYWHEEL HOUSING 

T122075 O-RING 2 ENGINE OIL COOLER 

U13639 O-RING 2 CYLINDER BLOCK 

R26375 O-RING 2 THERMOSTAT 

T122075 O-RING 2 OIL COOLER TO HOUSING 

R121424 O-RING 1 TIMING GEAR COVER 

R75892 O-RING 1 CYLINDER BLOCK 

R89944 O-RING 1 WATER PUMP 

R72328 O-RING 4 ENGINE OIL FILTER 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24 

H-2 

TABLE H-1. MANDATORY REPLACEMENT PARTS – CONT.

AR65507 O-RING KIT 6 CYLINDER LINER 

R63548 O-RING 1 TURBOCHARGER 

51M7040 O-RING 1 FUEL FILTER 

R61871 O-RING 1 OIL PUMP 

R123575 O-RING 6 ROCKER ARM COVER 

R61105 O-RING 2 ENGINE OIL COOLER 

51M7043 O-RING 1 2 OIL PAN 

R97185 O-RING 1 OIL PUMP 

51M7044 O-RING 1 17.300 X 2.200 MM TIMING GEAR COVER 

RE59754 OIL FILTER 1 

R500001 PACKING 1 (USE WITH RE500005) 

RE66271 PISTON RING KIT 6 PISTON RINGS 

RE50752 SEAL KIT 1 FUEL FILTER 

R26125 SPRING 12 CYLINDER HEAD 

R111137 SPRING 1 CYLINDER BLOCK 

T20314 SPRING 5 ROCKER ARM 

RE64354 THERMOSTAT 1 82° C (180°F) 

R131206 THRUST WASHER 1 CRANKSHAFT 

R131283 THRUST WASHER 1 CRANKSHAFT 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-1 

 INDEX 

 A

Aligning Pin Hole in Piston, Figure 5-60...........................................................................................................5-44 

 B

Battery Charging Alternator ..............................................................................................................................3-23, 4-14 

 Assembly ..................................................................................................................................................4-20 

 Assembly, Figure 4-2................................................................................................................................4-16 

 Mounting, Figure 3-4................................................................................................................................3-24 

 Inspection .................................................................................................................................................3-24 

 Installation ................................................................................................................................................3-25 

 Repair .......................................................................................................................................................4-15 

 Removal....................................................................................................................................................3-23 

 Replacement .............................................................................................................................................3-24 

 Test ...........................................................................................................................................................4-14 

 Test (Battery Charging Alternator Installed) ............................................................................................3-23 

 Test Circuit, Figure 4-1.............................................................................................................................4-14 

Bleeding Fuel System ........................................................................................................................................3-37 

 General .....................................................................................................................................................3-37 

 at Fuel Filter..............................................................................................................................................3-37 

 at Fuel Injection Nozzles ..........................................................................................................................3-38 

 at Fuel Injection Pump..............................................................................................................................3-38 

 C

Cam Advance Pin Removal, Figure 5-5.............................................................................................................5-11 

Cam Rollers And Shoes, Figure 5-21 ................................................................................................................5-21 

Cam Ring Removal, Figure 5-12 .......................................................................................................................5-15 

 Figure 5-18 ...............................................................................................................................................5-19 

Camshaft Lobe Height Specifications, Table 5-3 ..............................................................................................5-51 

Camshaft And Timing Gear Train Specifications, Table 5-4.............................................................................5-53 

Camshaft, Figure 5-61 .......................................................................................................................................5-47 

Camshaft Assembly ...........................................................................................................................................5-45 

 End Play Test............................................................................................................................................5-45 

 Inspection Prior to Camshaft Removal .....................................................................................................5-45 

 Installation ................................................................................................................................................5-51 

 Removal....................................................................................................................................................5-45 

 Replacement .............................................................................................................................................5-51 

 Test ...........................................................................................................................................................5-48 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-2 

 INDEX (Continued) 

 C (Continued) 

Checking 

 Timing Marks, Figure 4-42 ...................................................................................................................... 4-53 

 Brush Holder Assembly, Figure 4-30....................................................................................................... 4-33 

 Commutator Run-Out, Figure 4-21 .......................................................................................................... 4-29 

 Field Coils, Figure 4-31 ........................................................................................................................... 4-34 

 For Open Field Coil, Figure 4-32............................................................................................................. 4-34 

 For Open Circuit Windings, Figure 4-29 ................................................................................................. 4-33 

 Overrunning Clutch, Figure 4-26 ............................................................................................................. 4-31 

 Piston Ring Groove Clearance, Figure 5-75 ............................................................................................ 5-76 

 Piston Keystone Ring Groove Wear, Figure 5-74.................................................................................... 5-75 

Clip Removal, Figure 5-2.................................................................................................................................. 5-9 

Connecting Rod Bore (Without Bearing Inserts) Specifications, Table 5-7 ..................................................... 5-78 

 Piston Pin Bushing Specifications, Table 5-8 .......................................................................................... 5-79 

 Journal And Bearing Specifications, Table 5-6........................................................................................ 5-77 

 Assembly And Governor Spring Removal, Figure 5-4 ............................................................................ 5-10 

Control Rod Installation, Figure 5-49 ............................................................................................................... 5-38 

Control Spring Installation, Figure 5-48 ........................................................................................................... 5-37 

Cooling System................................................................................................................................................. 2-1 

 Maintenance............................................................................................................................................. 3-18 

 Maintenance, General .............................................................................................................................. 3-18 

Corrosion Prevention And Control ................................................................................................................... 1-2 

Crankshaft And Main Bearings......................................................................................................................... 5-59 

 Figure 5-67............................................................................................................................................... 5-60 

 Installation ............................................................................................................................................... 5-68 

 Inspection................................................................................................................................................. 5-62 

 Removal ................................................................................................................................................... 5-59 

 Repair....................................................................................................................................................... 5-67 

 Specifications, Table 5-5 ......................................................................................................................... 5-64 

Crankshaft End Play Test.................................................................................................................................. 5-62 

Crankshaft Pulley.............................................................................................................................................. 4-92 

 Figure 4-60............................................................................................................................................... 4-91 

 Inspection................................................................................................................................................. 4-92 

 Installation ............................................................................................................................................... 4-93 

 Removal ................................................................................................................................................... 4-92 

 Replacement............................................................................................................................................. 4-92 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-3 

 INDEX (Continued) 

 C (Continued) 

Crankshaft Pulley, Torsional Damper, And Timing Gear Cover Assembly Maintenance.................................4-90 

Critical Areas of Crankshaft Load Stress, Figure 5-68 ......................................................................................5-63 

Cylinder Block ..................................................................................................................................................5-90 

 Disassembly..............................................................................................................................................5-90 

 Reassembly...............................................................................................................................................5-97 

 Repair .......................................................................................................................................................5-91 

 Top Deck Specifications, Table 4-5 .........................................................................................................4-78 

Cylinder Head....................................................................................................................................................4-73, 5-104 

 Assembly ..................................................................................................................................................5-112 

 Assembly, Figure 4-49..............................................................................................................................4-75 

 Assembly Maintenance.............................................................................................................................4-63 

 Capscrew Torque Sequence, Figure 4-52 .................................................................................................4-79 

 Disassembly..............................................................................................................................................5-104 

 Inspection .................................................................................................................................................4-76 

 Installation ................................................................................................................................................4-78 

 Repair .......................................................................................................................................................5-105 

 Removal....................................................................................................................................................4-73 

 Testing Prior to Installation ......................................................................................................................4-77 

Cylinder Liners ..................................................................................................................................................5-83 

 And Block Specifications, Table 5-11......................................................................................................5-87 

 Height Specifications, Table 5-9 .............................................................................................................5-83 

 Inspection .................................................................................................................................................5-84 

 Installation ................................................................................................................................................5-89 

 Removal....................................................................................................................................................5-83 

 Repair .......................................................................................................................................................5-88 

 Testing Cylinder Liner Height Prior to Removal......................................................................................5-83 

 Thickness Specifications, Table 5-10 .......................................................................................................5-87 

 D

Damper Barrel and Piston, Figure 5-51 .............................................................................................................5-39 

Data Plates.........................................................................................................................................................1-5 

Delivery Valve, Figure 5-28 ..............................................................................................................................5-25 

 Removal, Figure 5-14 ...............................................................................................................................5-16 

Destruction of Army Material to Prevent Enemy Use .......................................................................................1-2 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-4 

 INDEX (Continued) 

 D (Continued) 

Direct Support Troubleshooting, Table 4-1 ...................................................................................................... 4-2 

Direct Support Troubleshooting Procedures..................................................................................................... 4-1 

Disconnecting Lead Wire (Typical), Figure 4-11 ............................................................................................. 4-24 

Drive Shaft Bearing and Seal Removal (Shown Removed), Figure 5-10.......................................................... 5-14

 Figure 5-17............................................................................................................................................... 5-18 

 Bearing Installation, Figure 5-31 ............................................................................................................. 5-27 

Droop Control Locking Cap Installation, Figure 5-50 ...................................................................................... 5-38 

 Removal, Figure 5-3 ................................................................................................................................ 5-9 

 E

Electrical System............................................................................................................................................... 2-2 

Electrical System Maintenance ......................................................................................................................... 3-23, 4-14 

Engine Components, Figure 1-1........................................................................................................................ 1-4 

Engine Description, General ............................................................................................................................. 1-2 

 Lubrication System .................................................................................................................................. 1-3 

 Camshaft .................................................................................................................................................. 1-2 

 Cooling System........................................................................................................................................ 1-3 

 Crankshaft................................................................................................................................................ 1-3 

 Cylinder Liners and Pistons ..................................................................................................................... 1-3 

 Detailed.................................................................................................................................................... 1-2 

 Electrical System...................................................................................................................................... 1-3 

 Fuel System.............................................................................................................................................. 1-3 

 Intake and Exhaust Valves ....................................................................................................................... 1-3 

 Turbocharger............................................................................................................................................ 1-2 

Engine, Inspection............................................................................................................................................. 1-8 

 Lifting, Figure 4-63.................................................................................................................................. 4-100 

 Option Codes - 6 Cylinder, 6.8 Liter, Table 1-2 ...................................................................................... 1-6 

 Timing Hole Location, Figure 4-46 ......................................................................................................... 4-66 

 Service ..................................................................................................................................................... 1-8 

Equipment Data, Leading Particulars................................................................................................................ 1-5 

Exhaust Manifold.............................................................................................................................................. 3-29, 4-45 

 Figure 3-8................................................................................................................................................. 3-29 

 Inspection................................................................................................................................................. 3-29, 4-45 

 Installation ............................................................................................................................................... 4-46 

 Removal ................................................................................................................................................... 4-45 

 Replacement............................................................................................................................................. 4-46 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-5 

 INDEX (Continued) 

 F

Fabrication of Tools and Equipment..................................................................................................................3-1 

Fan Drive Assembly, Figure 4-61......................................................................................................................4-93 

Fastening Cylinder Liners, Figure 5-70 .............................................................................................................5-71 

Flywheel ............................................................................................................................................................4-81 

 Flatness, Figure 4-53 ................................................................................................................................4-82 

 Flatness Specifications, Table 4-6 ............................................................................................................4-82 

 Inspection .................................................................................................................................................4-81 

 Installation ................................................................................................................................................4-83 

 Removal....................................................................................................................................................4-82 

 Removal, Figure 4-54 ...............................................................................................................................4-82 

 Replacement .............................................................................................................................................4-83 

 and Housing Assembly, Figure 4-58.........................................................................................................4-88 

 and Housing Assembly Maintenance........................................................................................................4-81 

Flywheel Housing ..............................................................................................................................................4-87 

 Inspection .................................................................................................................................................4-88 

 Removal....................................................................................................................................................4-87 

 Replacement .............................................................................................................................................4-88 

 Installation ................................................................................................................................................4-89 

Flywheel Ring Gear, Figure 4-55.......................................................................................................................4-83 

Front Plate .........................................................................................................................................................5-57 

 Figure 5-65 ...............................................................................................................................................5-57 

 Inspection .................................................................................................................................................5-58 

 Installation ................................................................................................................................................5-58 

 Removal....................................................................................................................................................5-57 

 Sealant Application, Figure 5-66 ..............................................................................................................5-59 

Fuel Filter ..........................................................................................................................................................3-42 

 Assembly, Figure 3-15..............................................................................................................................3-39 

 Installation ...............................................................................................................................................3-42 

 Remove Fuel Filter Element ....................................................................................................................3-42 

 Service ......................................................................................................................................................3-42 

Fuel Filter Base..................................................................................................................................................4-62 

 Installation ................................................................................................................................................4-62 

 Removal....................................................................................................................................................4-62 

 Repair .......................................................................................................................................................4-62 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-6 

 INDEX (Continued) 

 F (Continued) 

Fuel Injection Assembly, Figure 3-17............................................................................................................... 3-41 

Fuel Injection Nozzle Assembly ....................................................................................................................... 4-56 

 Figure 4-44............................................................................................................................................... 4-59 

 Inspection................................................................................................................................................. 3-49 

 Installation ............................................................................................................................................... 4-61 

 Removal ................................................................................................................................................... 4-56 

 Replacement............................................................................................................................................. 4-61 

 Test .......................................................................................................................................................... 4-57 

Fuel Injection Pump.......................................................................................................................................... 4-50, 5-2 

 Assembly.................................................................................................................................................. 5-26 

 Checks, Table 5-2 .................................................................................................................................... 5-5 

 Disassembly ............................................................................................................................................. 5-5 

 Figure 5-1................................................................................................................................................. 5-6 

 Inspection................................................................................................................................................. 3-49, 4-53 

 Installation ............................................................................................................................................... 4-54 

 Pressure Outlet Ports, Figure 4-43 ........................................................................................................... 4-55 

 Removal ................................................................................................................................................... 4-50 

 Repair....................................................................................................................................................... 5-17 

 Replacement............................................................................................................................................. 4-53 

 Test .......................................................................................................................................................... 5-2 

Fuel Lines.......................................................................................................................................................... 3-47 

 Inspection................................................................................................................................................. 3-48 

 Installation ............................................................................................................................................... 3-48 

 Removal ................................................................................................................................................... 3-47 

 Replacement............................................................................................................................................. 3-48 

Fuel Side Seal Installation, Figure 5-29 ............................................................................................................ 5-26 

Fuel Supply Pump, Figure 3-16 ........................................................................................................................ 3-40 

Fuel System....................................................................................................................................................... 2-1 

 Maintenance............................................................................................................................................. 4-50, 5-2 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-7 

 INDEX (Continued) 

 F (Continued) 

Fuel Transfer Supply Pump ...............................................................................................................................3-43 

 Bench Test................................................................................................................................................3-45 

 Inspection .................................................................................................................................................3-45 

 Installation ................................................................................................................................................3-46 

 Replacement .............................................................................................................................................3-46 

 Removal....................................................................................................................................................3-44 

 Test On Engine .........................................................................................................................................3-43 

Fuel Transfer Pump Push Rod Location, Figure 4-50 .......................................................................................4-76 

G

Gasket Application to Cylinder Block, Figure 4-58 ..........................................................................................4-89 

General ..............................................................................................................................................................4-13 

 Maintenance..............................................................................................................................................3-15 

General Support Troubleshooting Procedures...................................................................................................5-1 

Governor Arm and Linkage Hook Removal, Figure 5-9 ...................................................................................5-13 

Governor Weight Installation, Figure 5-44........................................................................................................5-35 

Growler Test, Figure 4-27 .................................................................................................................................4-32 

H 

Head and Rotor Assembly Installation, Figure 5-47..........................................................................................5-36 

Housing Assembly, Figure 5-16 ........................................................................................................................5-17 

Hydraulic Head Assembly, Figure 5-19.............................................................................................................5-20 

 Removal, Figure 5-8 .................................................................................................................................5-12 

 I

Idler Gears and Idler Gear Shafts ......................................................................................................................5-53 

 Figure 5-63 ...............................................................................................................................................5-55 

 End Play and Backlash Test......................................................................................................................5-53 

 Installation ................................................................................................................................................5-56 

 Removal....................................................................................................................................................5-54 

 Test ...........................................................................................................................................................5-55 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-8 

 INDEX (Continued) 

 I (Continued) 

Inspecting 

 Cylinder Block, Figure 5-81 .................................................................................................................... 5-94 

 Cylinder Liner Pitting, Figure 5-78.......................................................................................................... 5-85 

 Piston Cooling Orfice, Figure 5-79.......................................................................................................... 5-92 

 and Replacing Bearings, Figure 4-24....................................................................................................... 4-30 

 and Servicing Engine ............................................................................................................................... 1-8 

 Turbocharger Bearings, Figure 4-38 ........................................................................................................ 4-43 

Installing 

 Brushes, Figure 4-33................................................................................................................................ 4-35 

 Cover On Yoke, Figure 4-34.................................................................................................................... 4-36 

 Rollers and Shoes (Typical), Figure 5-39 ................................................................................................ 5-31 

 Yoke, Figure 4-35 .................................................................................................................................... 4-36 

Intake and Exhaust System Maintenance .......................................................................................................... 3-28, 4-37 

 Adjust....................................................................................................................................................... 4-64 

 Test Valve Lift ......................................................................................................................................... 4-68 

 Test Valve Clearance ............................................................................................................................... 4-67 

Intake Manifold................................................................................................................................................. 3-28, 4-44 

 Figure 3-7................................................................................................................................................. 3-28 

 Inspection................................................................................................................................................. 3-28, 4-44 

 Installation ............................................................................................................................................... 4-44 

 Pressure Check......................................................................................................................................... 3-17 

 Removal ................................................................................................................................................... 4-44 

 Replacement............................................................................................................................................. 4-44 

Introduction....................................................................................................................................................... 2-1 

 L

Leaf Springs, Figure 5-22 ................................................................................................................................. 5-21 

Linkage Hook Disconnection, Figure 5-7 ......................................................................................................... 5-12 

Lubrication Instructions .................................................................................................................................... 3-1 

Lubrication System ........................................................................................................................................... 2-1 

 Maintenance............................................................................................................................................. 3-29, 4-46 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-9 

 INDEX (Continued) 

 M

Maintenance Repair Parts ..................................................................................................................................3-1 

Measuring 

 Engine Blow-by ........................................................................................................................................3-16 

 Brush Length, Figure 4-25........................................................................................................................4-31 

 Cam Follower Bore Diameter, Figure 5-83 ..............................................................................................5-95 

 Camshaft Bore Diameter, Figure 5-84......................................................................................................5-96 

 Camshaft Lobe Height, Figure 5-62..........................................................................................................5-50 

 Commutator OD, Figure 4-22...................................................................................................................4-29 

 Cylinder Block Top Deck Flatness, Figure 5-85 ......................................................................................5-96 

 Cylinder Head Thickness, Figure 5-91 .....................................................................................................5-108 

 Main Bearing Bore, Figure 5-82...............................................................................................................5-95 

 Main Thrust Journal and Thrust Bearing Width, Figure 5-69...................................................................5-65 

 Piston Skirt, Figure 5-76...........................................................................................................................5-76 

 Rod Center-to-Center Bores, Figure 5-77.................................................................................................5-80 

 Roller to Roller Dimension, Figure 5-40 ..................................................................................................5-32 

 Segment Mica Depth, Figure 4-23............................................................................................................4-30 

Metering Valve and Arm Assembly, Figure 5-27 ..............................................................................................5-25 

 N

Nuclear, Biological, Chemical (NBC) Decontamination Procedures ................................................................2-2 

 O

Oil Bypass Valve Assembly ..............................................................................................................................5-102 

 Figure 5-89 ...............................................................................................................................................5-103 

 Inspection .................................................................................................................................................5-103 

 Installation ................................................................................................................................................5-104 

 Removal....................................................................................................................................................5-102 

 Replacement .............................................................................................................................................5-103 

Oil Cooler ..........................................................................................................................................................3-31 

 Assembly, Figure 3-10..............................................................................................................................3-32 

 Inspection .................................................................................................................................................3-31 

 Installation ................................................................................................................................................3-33 

 Removal....................................................................................................................................................3-31 

 Replacement .............................................................................................................................................3-32 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-10 

 INDEX (Continued) 

 O (Continued) 

Oil Dipstick Tube.............................................................................................................................................. 3-34 

 Inspection................................................................................................................................................. 3-34 

 Installation ............................................................................................................................................... 3-35 

 Installation, Figure 3-13........................................................................................................................... 3-35 

 Removal ................................................................................................................................................... 3-35 

 Replacement............................................................................................................................................. 3-35 

 Assembly, Figure 3-12 ............................................................................................................................. 3-34 

Oil Fill Tube...................................................................................................................................................... 3-33 

 Assembly, Figure 3-11 ............................................................................................................................. 3-33 

 Inspection................................................................................................................................................. 3-34 

 Installation ............................................................................................................................................... 3-34 

 Removal ................................................................................................................................................... 3-33 

 Replacement............................................................................................................................................. 3-34 

Oil Filter Assembly........................................................................................................................................... 3-29 

 Figure 3-9................................................................................................................................................. 3-30 

 Inspection................................................................................................................................................. 3-29 

 Installation ............................................................................................................................................... 3-30 

 Replacement............................................................................................................................................. 3-30 

 Removal ................................................................................................................................................... 3-29 

Oil Gallery Plugs, Figure 5-80 .......................................................................................................................... 5-92 

Oil Pan .............................................................................................................................................................. 4-48 

 Figure 3-14............................................................................................................................................... 3-36 

 Inspection................................................................................................................................................. 3-36, 4-48 

 Installation ............................................................................................................................................... 4-49 

 Removal ................................................................................................................................................... 4-48 

 Replacement............................................................................................................................................. 4-49 

Oil Pressure Regulating Valve Assembly ......................................................................................................... 4-46 

 Figure 4-39............................................................................................................................................... 4-47 

 Inspection................................................................................................................................................. 4-47 

 Installation ............................................................................................................................................... 4-48 

 Removal ................................................................................................................................................... 4-46 

 Replacement............................................................................................................................................. 4-48 

 Valve Seat Replacement .......................................................................................................................... 5-114 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-11 

 INDEX (Continued) 

 O (Continued) 

Oil Pump Assembly ...........................................................................................................................................5-98 

 Figure 5-86 ...............................................................................................................................................5-99 

 Axial Clearance Measurement, Figure 5-87 .............................................................................................5-101 

 Installation ................................................................................................................................................5-102 

 Inspection .................................................................................................................................................5-100 

 Radial Clearance Measurement, Figure 5-88............................................................................................5-101 

 Removal....................................................................................................................................................5-99 

 Replacement .............................................................................................................................................5-102 

Oil Side Seal Installation, Figure 5-30...............................................................................................................5-27 

Option Code Label, Figure 1-2 ..........................................................................................................................1-5 

 P

Pick-Up Tube Assembly....................................................................................................................................4-49 

 Figure 4-40 ...............................................................................................................................................4-49 

 Inspection .................................................................................................................................................4-49 

 

Piston Inspection, Figure 5-73 ...........................................................................................................................5-75 

Piston and Piston Ring Seal, Figure 5-55 ..........................................................................................................5-41 

Piston in Power Side Piston Hole, Figure 5-58..................................................................................................5-43 

Piston Ring Compressor, Figure 5-57................................................................................................................5-42 

 Figure 5-56 ...............................................................................................................................................5-42 

Pistons and Connecting Rods.............................................................................................................................5-70 

 Installation ................................................................................................................................................5-82 

 Removal....................................................................................................................................................5-70 

 Repair .......................................................................................................................................................5-72 

 and Cylinder Liners, Figure 5-72..............................................................................................................5-74 

PMCS Procedures..............................................................................................................................................3-1 

Power Side Piston Hole Plug Installation, Figure 5-59......................................................................................5-43 

Preparation for Storage or Shipment..................................................................................................................1-2 

Preventive Maintenance Checks and Services (PMCS), Table 3-1 ...................................................................3-2 

Procedural Index, General Support Maintenance ..............................................................................................5-1 

Pumping Plunger Installation, Figure 5-38 ........................................................................................................5-31 

 Removal, Figure 5-13 ...............................................................................................................................5-15 

Purpose 

 of Troubleshooting Flowchart...................................................................................................................3-3, 4-1 

 of Equipment ............................................................................................................................................1-1 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-12 

 INDEX (Continued) 

 R

Rear Crankshaft Oil Seal/Wear Sleeve Assembly............................................................................................. 4-84 

 Removal of Rear Crankshaft Oil Seal, Figure 4-56.................................................................................. 4-84 

 Removal ................................................................................................................................................... 4-84 

 Replacement............................................................................................................................................. 4-85 

 Installation ............................................................................................................................................... 4-86 

 Installation of Rear Crankshaft Oil Seal, Figure 4-57 .............................................................................. 4-86 

 Inspection................................................................................................................................................. 4-85 

Reed Valve Assembly, Figure 5-54 .................................................................................................................. 5-41 

 Removal, Figure 5-6 ................................................................................................................................ 5-11 

Regulator Assembly Installation, Figure 5-43................................................................................................... 5-34 

Removing 

 Armature, Figure 4-15.............................................................................................................................. 4-26 

 Brushes, Figure 4-14................................................................................................................................ 4-25 

 Carbon From Cylinder Liners, Figure 5-71.............................................................................................. 5-71 

 Overrunning Clutch (Typical), Figure 4-17 ............................................................................................. 4-27 

 Pinion, Retainer, and Rollers (Typical), Figure 4-19 ............................................................................... 4-28 

 Housing (Typical), Figure 4-16................................................................................................................ 4-26 

 Rear Crankshaft Oil Seal, Figure 4-56 ..................................................................................................... 4-84 

 Starter End Frame and Yoke Assembly, (Typical), Figure 4-13 .............................................................. 4-25 

 Steel Ball, Figure 4-18 ............................................................................................................................. 4-27 

 Through Bolts (Typical), Figure 4-12...................................................................................................... 4-24 

 Valve Seat Insert, Figure 5-93 ................................................................................................................. 5-111 

 Washer and Spring, Figure 4-20 .............................................................................................................. 4-28 

Reporting 

 Equipment Improvement Recommendations (EIR) ................................................................................. 1-1 

 Item and Packaging Discrepancies........................................................................................................... 1-1 

 Equipment Improvement Recommendations (EIR), Army ...................................................................... 1-1 

 Equipment Improvement Recommendations (EIR), Air Force ................................................................ 1-1 

 Equipment Improvement Recommendations (EIR), Marine Corps.......................................................... 1-2 

Reports of Maintenance and Unsatisfactory Equipment ................................................................................... 1-1 

Retaining Clip Removal, Figure 5-15 ............................................................................................................... 5-16 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-13 

 INDEX (Continued) 

 R (Continued) 

Rocker Arm Assembly.......................................................................................................................................4-70 

 Figure 4-48 ...............................................................................................................................................4-70 

 Adjust .......................................................................................................................................................4-71 

 Installation ................................................................................................................................................4-73 

 Removal....................................................................................................................................................4-70 

 Repair .......................................................................................................................................................4-71 

 Replacement .............................................................................................................................................4-72 

Rocker Arm Cover.............................................................................................................................................4-63 

 Figure 4-45 ...............................................................................................................................................4-65 

 Installation ................................................................................................................................................4-64 

 Removal....................................................................................................................................................4-63 

 Replacement .............................................................................................................................................4-63 

Rocker Arm Location, Figure 4-47....................................................................................................................4-67 

Rotor Assembly, Figure 5-20.............................................................................................................................5-20 

 S

Seal Protection Tube, Figure 5-32 .....................................................................................................................5-28 

Separating Gear and Shaft, Figure 4-44.............................................................................................................4-52 

Setting Governor Linkage Gap, Figure 5-53......................................................................................................5-40 

Short Block Assembly .......................................................................................................................................5-45 

Spring Pin Protrusion, Figure 5-64 ....................................................................................................................5-56 

Spring Washer and Retaining Ring, Figure 5-34 ...............................................................................................5-29 

Stand, Vehicle Engine........................................................................................................................................4-98 

Starter ................................................................................................................................................................3-25, 4-21 

 Assembly ..................................................................................................................................................4-35 

 Assembly, Figure 3-6................................................................................................................................3-27 

 Bench Test Setup, Figure 4-9 ...................................................................................................................4-22 

 Inspection .................................................................................................................................................3-26 

 Installation ................................................................................................................................................3-26 

 Removal....................................................................................................................................................3-26 

 Repair .......................................................................................................................................................4-24 

 Replacement .............................................................................................................................................3-26 

 Test ...........................................................................................................................................................4-21 

 Test (Installed on Generator)....................................................................................................................3-25 

 Solenoid Test Circuit, Figure 3-5 .............................................................................................................3-25 

Stator and Rear Housing Separation, Figure 4-3 ...............................................................................................4-17 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-14 

 INDEX (Continued) 

 T

Table of Specifications, Table 1-1 .................................................................................................................... 1-5 

Testing 

 Cylinder Liner Height Prior to Cylinder Liner Removal.......................................................................... 5-78 

 Engine Compression Pressure.................................................................................................................. 3-16 

 For Grounded Windings, Figure 4-28...................................................................................................... 4-32 

 Brush Assembly, Figure 4-4..................................................................................................................... 4-17 

 Exciting Diodes, Figure 4-5 ..................................................................................................................... 4-18 

 Positive/Negative Diodes, Figure 4-6 ...................................................................................................... 4-18 

 Rotor, Figure 4-8...................................................................................................................................... 4-20 

 Stator Windings, Figure 4-7..................................................................................................................... 4-19 

Thermostat and Water Manifold/Thermostat Cover ......................................................................................... 3-18 

 Figure 3-1................................................................................................................................................. 3-19 

 Inspection................................................................................................................................................. 3-19 

 Installation ............................................................................................................................................... 3-20 

 Installation, Figure 3-2............................................................................................................................. 3-21 

 Removal ................................................................................................................................................... 3-18 

 Replacement............................................................................................................................................. 3-20 

Throttle Installation, Figure 5-52 ...................................................................................................................... 5-39 

Thrust Bearing and Thrust Washer, Figure 5-33............................................................................................... 5-28 

 Sleeve Installation, Figure 5-46 ............................................................................................................... 5-36 

Thrust Washer Installation, Figure 5-45 ........................................................................................................... 5-35 

Tightening Delivery Valve Stop Screw, Figure 5-37 ........................................................................................ 5-30 

Timing Gear 

 Cover........................................................................................................................................................ 4-93 

 Cover, Figure 4-62 ................................................................................................................................... 4-95 

 Cover, Inspection ..................................................................................................................................... 4-94 

 Cover, Installation.................................................................................................................................... 4-96 

 Cover, Removal ....................................................................................................................................... 4-93 

 Cover, Replacement................................................................................................................................. 4-96 

Timing Mark Locator, Figure 5-35 ................................................................................................................... 5-29 

Tools and Equipment ........................................................................................................................................ 3-1 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-15 

 INDEX (Continued) 

 T (Continued) 

Torsional Damper..............................................................................................................................................4-90 

 Inspection .................................................................................................................................................4-90 

 Installation ................................................................................................................................................4-92 

 Removal....................................................................................................................................................4-91 

 Replacement .............................................................................................................................................4-91 

Transfer Pump 

 Blades, Figure 5-23...................................................................................................................................5-22 

 Blade Installation, Figure 5-42 .................................................................................................................5-33 

 End Cap Seal Removal, Figure 5-11.........................................................................................................5-14 

 Liner, Figure 5-24.....................................................................................................................................5-23 

 Liner Installation, Figure 5-41 ..................................................................................................................5-33 

 Regulator Assembly, Figure 5-26 .............................................................................................................5-24 

 Regulating Piston and Adjusting Screw, Figure 5-25 ...............................................................................5-23 

Transportation Discrepancy Report (TDR) (SF 361) ........................................................................................1-1 

Turbocharger .....................................................................................................................................................4-37 

 Figure 4-36 ...............................................................................................................................................4-39 

 Inspection .................................................................................................................................................4-38 

 Inspection Points, Figure 4-37 ..................................................................................................................4-40 

 Inspecting Turbocharger Bearings, Figure 4-38 .......................................................................................4-43 

 Install ........................................................................................................................................................4-42 

 Removal....................................................................................................................................................4-37 

 Replacement .............................................................................................................................................4-41 

 Test ...........................................................................................................................................................4-41 

Type of Manual .................................................................................................................................................1-1 

 U

Unit Troubleshooting Procedures ......................................................................................................................3-3 

Unit Troubleshooting, Table 3-2 .......................................................................................................................3-4 
ARMY TM 9-2815-260-24 

AIR FORCE TO 38G1-126-2 

MARINE CORPS TM 09244A/09245A-24

Index-16 

 INDEX (Continued) 

 V

Valve 

 Clearance Specification (Rocker Arm-To-Valve Tip), Table 4-2............................................................ 4-68 

 Face Angle, Figure 5-90........................................................................................................................... 5-106 

 Guide Installation, Figure 5-95 ................................................................................................................ 5-113 

 Lift Specifications at 0.00 in. (mm) Valve Clearance, Table 4-3............................................................. 4-69 

 Recess Measurement, Figure 4-51 ........................................................................................................... 4-76 

 Recess Specifications, Table 4-4.............................................................................................................. 4-77 

 Seat Bore in Cylinder Head Measurement, Figure 5-94 .......................................................................... 5-112 

 Seat Bore Insert Specifications, Table 5-12............................................................................................. 5-113 

 Seat Removal Chisel, Figure 5-92............................................................................................................ 5-111 

 W

Warranty .......................................................................................................................................................... 1-2 

Water Pump ...................................................................................................................................................... 3-21 

 Assembly, Figure 3-3 ............................................................................................................................... 3-22 

 Inspection................................................................................................................................................. 3-22 

 Installation ............................................................................................................................................... 3-22 

 Removal ................................................................................................................................................... 3-21 

 Replacement............................................................................................................................................. 3-22 

Weight Retaining Assembly, Figure 5-36 ......................................................................................................... 5-30 
RECOMMENDED CHANGES TO EQUIPMENT TECHNICAL PUBLICATIONS

PREVIOUS

ARE OBSOLETE

P.S. - IF YOUR OUTFIT WANTS TO KNOW ABOUT

RECOMMENDATION MAKE A CARBON COPY OF DA 2028-2 AND GIVE IT TO YOUR

FORM

1 JUL 79

BE EXACT PIN-POINT WHERE IT

SOMETHING WRONG

PUBLICATION PUBLICATION DATE PUBLICATION

IN THIS SPACE TELL WHAT IS WRONG

AND WHAT SHOULD BE DONE ABOUT IT:

DATE SENT

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TM 11-5840-340-12 23 Jan 74 Radar Set AN/PRC10 July 1975

Commander

Stateside Army Depot

ATTN: AMSTA-US

Stateside, N.J. 07703-5007

2-25 2-28

3-10 3-3 3-1

5-85-6

FO-3

Recommend that the installation antenna alignment

procedure be changed throughout to specify a 20 IFF

antenna lag rather than 10.

REASON: Experience has shown that with only a 10 lag,

the antenna servo system is too sensitive to wind gusting

excess of 25 knots, and has a tendency to rapidly accelerate

and decelerate as it hunts, causing strain to the drive train.

Hunting is minimized by adjusting the lag to 20

degradation of operation.

Item 5, Functional column. Change “2 dB" to “3 dB”.

REASON: The adjustment procedure for the TRANS POWER

FAULT indicator calls for a 3 dB (500 watts) adjustment to light

the TRANS POWER FAULT indicator.

Add new step f.1 to read, “Replace cover plate removed in

step e.1, above."

REASON: To replace the cover plate.

Zone C 3. On J1-2, change “+24 VDC" to “+5 VDC".

REASON: This is the output line of the 5 VDC power supply.

+24 VDC is the input voltage.

SSG I. M. DeSpiritof 999-1776
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 and Fort Monmouth

ATTN: AMSEL-LC-LEO-D-CS-CFO

Fort Monmouth, New Jersey 07703-5000

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Fort Monmouth, New Jersey 07703-5006

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Fort Monmouth, New Jersey 07703-5006

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 and Fort Monmouth

ATTN: AMSEL-LC-LEO-D-CS-CFO

Fort Monmouth, New Jersey 07703-5006

PLEASE

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REQUIRED
By Order of the Secretary of the Army: 

 ERIC K. SHINSEKI 

 General, United States Army 

 Official: Chief of Staff

 

 0030004 

By Order of the Secretary of the Marine Corps: 

 RANDALL P. SHOCKEY

 Director, Program Support 

 Marine Corps Systems Command 

By Order of the Secretary of the Air Force: 

 MICHAEL E. RYAN 

 General, United States Air Force 

 Chief of Staff 

 Official: 

 LESTER L. LYLES 

 General, United States Air Force 

 Commander, AFMC 

 

DISTRIBUTION: 

To be distributed in accordance with the initial distribution number (IDN) 256650 requirements 

for TM 9-2815-260-24. 
PIN: 078594-000