### ALERT SERVICE BULLETIN

DAT E REVISION NOTICE

A Subsid iar y of T e xtron Inc. Dec 01, 2004

TO: All O w ners/Operators of Bell 206L4 Helicopters

SUBJ ECT: REVISION “A” TO ALERT SERVI CE BUL L ETIN 206L-04-129: (FREEWHEEL AFT BEARING CAP 406-040-509-101, INSPECTION AND REWORK OF)

Revis i on “A” to this bulletin mandates the replacement of the output shaft 406-040-517

- 101 and s p rag and retainer 406-040-580-103 for freewheel with discrepant aft bearin g cap installed.

AN APPRO P RIA T E ENTRY S H OULD BE MADE I N TH E AIRCRAFT LOG B O O K UP O N ACCO MPLIS H MENT
IF O W NE RSHIP O F AIRCRAFT HAS CHANG E D P L EASE FO RWA RD TO NEW OWNERNO.

DATE

PAGE DATE

REV 

### ALERT SERVICE BULLETIN

A Subsidiary of Textron Inc.

AN APPROPRIATE ENTRY SHOULD BE MADE IN TH E AIRCRAFT LOGBOOK UPON ACCOMPLISHMENT

IF OWNERSHIP OF AIRCRAFT HAS CHANGED PLEASE FORWARD TO NEW OWNER 206L-04-129

12-01-04 July 19, 2004

“A” 1 of 13

MODEL AFFECTED: 206L4

SUBJECT: Freewheel aft bearing cap 406-040-509-101, inspection and recall of

HELICOPTERS AFFECTED: Model 206L4.

Freewheel aft bearing cap P/N 406-040-509-101,

serial numbers A-1833 thru A-1912.

COMPLIANCE: PART I

Upon receipt of this bulletin, determine if the aft bearing cap is affected. This applies to all spare aft bearing caps and freewheel assembly as well as those installed on the helicopter.

PART II

-NOTEEngine cycle start average can be calculated by subtracting the actual engi ne start cycle count from the engine start cycles at which time the freewheel was installed and dividing by the freewheel time

since new or time between overhaul. Example:

5000 cycles Total of actual engine cycle start

- 3000 cycles Total of engine cycle start at the freewheel installation 2000 cycles Total of start cycle on freewheel assembly
2000 cycles Total of start cycle on freewheel assembly

÷ 1000 hrs Freewheel (TSN) or(TSO) 2 cycles/h rs Engine cycle start averageASB 206L-04-129 Page 2 of 13

For freewheel assem b lies with less than 3 engine start cycles per hour on av erage and helic opters that are not exclusively used for training, ac complish

PART II o f this bulle tin wit hin the next 50 flighthours.

PART III

For helicopters exclusively us ed f o r training, and for

freewheel assemblies with 3 engine start cycles or more per hour on average, accomplish PART III of

this bulletin within the next 50 flight-hours.

If the freewheel as sembly is removed for any reason, accomplish PART III of this bulletin.

PART IV

For freewheel assem b ly equ ipped with aft cap as

described in the HELICOPT ER AFFECTED section, accomplish PART IV of this bulletin within the next 300 hours, but not later than 30 June 2005. A

DES CRIPT ION:

Bell Helicopter has found that some fr eewheel aft bearing c a ps are missing the

lubrication channel int ended to allow oil flow into the a ft bearing support assembly. These caps may have been deliv ered on production airc raft or as spares.

PART I of this bulletin gives instructions how to identify the affected aft cap.

PART II and III of this bulletin provides proc edures required to r e turn the freewheel assembly to service.

PART IV of this bullet i n mandates the replacement of the output shaft 406-040-517- 101 and sprag and retainer 406- 040-580-103 for freewheel wit h dis c repant aft bearing cap installed. A

APP R OVAL:

The engineering design aspects of this bulletin are Transport Canada approved.ASB 206L-04-129 Page 3 of 13

MANPOWER:

Approximately 0.5 man-hour is required to complete PART I of thi s bulletin. Approximately 3.0 man-hours are required to complete PART II of this bulletin. Approx imately 16.0 man-hours are required to complete PART III o f this bulletin. Approximately 16.0 man-hours ar e required to complete PART IV of this bulletin.

Man-hours are bas ed on hands- on time, and may vary with pe rsonnel and facilities

available. A

WARRANTY:

Owner/Operators of the affect ed helic opters who comply wit h the instructions outlined in this bulletin will receive a special 100% warranty credit for the replac ement parts contained in the “Required Material” section of this bulletin.

Owner/Operators that comply with PART II of this A SB will rec e ive $ 150. 00 labor credit, Owner/Operators that comply with PART III of this ASB will receive $800.00 labor credit. An additional $100.0 will be issued for customers t hat elect local r e work of the aft bearing cap.

Purchase the required parts from an appr oved BHTI supply source. Submit a completed Maintenance Malfunction Informa tion Report (MMIR) to BHTI Warranty Department no later than 30 days afte r completion of this bulletin.

MATERIAL:

Required Material: The following material is required for the ac complishm ent of this bulletin and may be obtained through your Bell Helico pter Textron Supply Center.

PART II

Part Number Nomenclature Quantity

214-040-814-105 SLEEVE A/R (NOTE 1)

214-040-84 1

- 1 0 1 S E A L 1

4 0 6

- 0 4 0

- 5 0 9

- 1 0 1 A F T BEARING CAP A/R (NOTE 2)

4 0 6

- 0 4 0

- 5 3 2

- 1 0 3 B E A R I N G A/R (NOTE 1)

M 8 3 2 4 8 / 1

- 0 1 8 P A C K I N G 1

M 8 3 2 4 8 / 1

- 0 2 1 P A C K I N G 1

M 8 3 2 4 8 / 1

- 1 4 0 P A C K I N G 1
MS24665- 2 8 5 C O T T E R P I N 1ASB 206L-04-129 Page 4 of 13

NOTE: 1. Bearing and sleeve replacement may not be necessary depending on the parts

condition. 2. Aft bearing cap replacement may not be required depending on the option chosen by the operator.

PART III

Part Number Nomenclature Quantity

206-040-279-101 PACKING 1

214-040-841-101 SEAL 1

214-040-814-105 SLEEVE A/R (NOTE 1)

406-040-509-109 AFT BEARING CAP A/R (NOTE 2)

406-040-516-101 INPUT SH AFT A/R (NOTE 1)

406-040-517-101 OUTPUT SHAFT 1

406-040-530-103 BEARING A/R (NOTE 1and 3)

406-040-532-103 BEARING A/R (NOTE 1 and 4)

407-340-533-101 BEARING A/R (NOTE 1 and 5)

406-040-580-103 SPRAG AND RETAINER 1
M83248/1-011 PACKING 5
M83248/1-016 PACKING 1
M83248/1-018 PACKING 1
M83248/1-021 PACKING 1
M83248/1-033 PACKING 1
M83248/1-034 PACKING 1
M83248/1-036 PACKING 1
M83248/1-140 PACKING 1
M83248/1-240 PACKING 1
M83248/1-238 PACKING 1
M83248/1-903 PACKING 1
M83248/1-906 PACKING 1
M83248/1-907 PACKING 1
MS24665-285 COTTER PIN 1

NOTE: 1. Replacement of bearing, input shaft, and sleeve, may not be necessary depending on the parts condition. 2. Aft bearing cap may not be required depending on the option chosen by the
operator. 3. As an alternate, it is acceptable to use 406-040-530-105 or 206-040-206-001 in lieu of 406-040-530-103 bearing. 4. As an alternate, it is acceptable to use 406-040-532-101 in lieu of 406-040-532- 103 bearing. 5. As an alternate, it is acceptable to use 206-040-206-001 or 206-040-206-101 in lieu of 407-340-533-101 bearing.ASB 206L-04-129 Page 5 of 13

PART IV

A Part Number Nomenclature Quantity

2 0 6

- 0 4 0

- 2 7 9

- 1 0 1 P A C K I N G 1

406-040-517-101 OUTPUT SHAFT 1

406-040-580-103 SPRAG AND RET A INER 1

M 8 3 2 4 8 / 1

- 0 1 1 P A C K I N G 5

M 8 3 2 4 8 / 1

- 0 1 6 P A C K I N G 1
M83248/1-018 PACKING 1

M 8 3 2 4 8 / 1

- 0 2 1 P A C K I N G 1

M 8 3 2 4 8 / 1

- 0 3 3 P A C K I N G 1

M 8 3 2 4 8 / 1

- 0 3 4 P A C K I N G 1
M83248/1-036 PACKING 1

M 8 3 2 4 8 / 1

- 1 4 0 P A C K I N G 1
M83248/1-240 PACKING 1

M 8 3 2 4 8 / 1

- 2 3 8 P A C K I N G 1
M83248/1-903 PACKING 1

M 8 3 2 4 8 / 1

- 9 0 6 P A C K I N G 1
M83248/1-907 PACKING 1
MS24665- 2 8 5 C O T T E R P I N 1

SPECIAL TOOLS:

None required

WEIGHT AND BAL ANCE:

Not required

ELECTRICAL LOAD DATA:

Not affecte d

REFE RE NCES:

BHT-206L4-MM, Rev. 4 – 22 December 2003

Chapter 63, Main Rotor Drive System

BHT-206L- CR&O, Reissue 0 – 18 June 1993ASB 206L-04-129 Page 6 of 13

Chapter 63, Main Rotor Drive System

PUBLICATIONS AFFECTED:

None affected

ACCOMPLISHMENT INSTRUCTIONS:

PART I: Identification of the af fected aft bearing cap, 406-040-509-101

1. Open the engine access doors.

2. Locate the serial number (1, Figure 1) of the freewheel aft bearing cap (2).

a. If the cap serial number is not list ed in the HELICOPTER AFFECTED section, no further action is required. Close t he access doors and continue with Step 3.

b. If the cap serial number is listed in HELICOPTER AFFECTED section, refer to

the COMPLIANCE section and accomplish either PART II or III of this bulletin as directed. Contact Product Support En gineering Light Helicopters with the P/N, S/N, TSN, and TS O of the aft bearing c ap and freewheel assembly:

Product Support Engineering Light Helicopters

Office: 450-971-6407

Fax: 450-433-0272

E-mail: pselight@bellhelic opter.textron.com

3. Make an entry in the helic opter Technical Records to s how that PART I of the Alert Service Bulletin is completed.

PART II. For freewheel assemblies with an average of less than 3 engine start cycle per hour and for helicopter that are not exclusively used for training

1. Remove the engine cowl ing and transmission fairing assembly (BHT-206L4-MM, Chapter 53).

2. Remove the forward short shaft (BHT-206L4-MM, Chapter 65).

3. Remove the aft adapter (5, Figure 2) and aft bearing cap (2) (BHT-206L4-MM, Chapter 63).ASB 206L-04-129 Page 7 of 13

4. Remove bearing (1) from the aft bearing cap (2) (BHT-206L4-MM, Chapter 63).

5. Remove and discard the support assembly seal (3).

6. Inspect support assembly bearing (1) for condition (BHT-206L-CR&O). Replace bearing if defective.

7. Inspect sleeve (4) for condition (BHT-206L-CR&O).

8. Select from the following list, t he rework option deemed most suitable for

convenience:

a. Order a replacement cap assembly through your Bell Helicopter Spares supplier. Please note that limited assets are available to support this bulletin, and spares will be issued on a first come, first served basis.

b. Locally rework the aft bear ing cap as shown in Figure 3. Use a vibrating stylus to identify locally-reworked cap assembly by adding letter "R" to the serial number on the cap.

c. Provide the cap for rework to Bell Tennessee. This option permits the original cap to be reworked by Bell Tennesee, id entified with the rewo rk letter "R" suffix to the serial number, and returned for installation.

d. Obtain a reworked cap from the rotable pool availabl e through Bell Tennessee. This option will accept the rework c andidate in exchange for a reworked item from the rotable pool. Pl ease note that for this opt ion due to limited assets, a rework candidate must be supplied in adv ance of shipment from the rotable pool.

e. For option c or d above, contact Bell Tennesee for advance scheduling at:

Bell Helicopter Tennessee Textron

157 Industrial Park Road Piney Flats, TN. 37686

Office: 423-538-5114

Fax: 423-538-6198.

9. Install the support assembly bearing (1) and seal (3) into the aft bearing cap (2) (BHT-206L4-MM, Chapter 63).

10. Install the aft bearing cap (2) and adapter (5) (BHT-206L4-MM, Chapter 63).

11. Install the forward short shaft (BHT-206L4-MM, Chapter 65).ASB 206L-04-129 Page 8 of 13

12. Check the freewheel and transmission chip detectors for presence of metal contamination (BHT- 206L4-MM, Chapter 63).

13. Install the engine cowling and trans mission fairing assembly (BHT-407-MM, Chapter 53).

14. Perform a 30 minute ground run as follow:

a. Perform normal start as per Flight Manual.

b. Operate the helicopter until it reaches 100% Nr then roll the throttle back to idle speed as you would do during normal operation.

c. Repeat the above step one time every 2 minutes until the 30 minute ground run is completed.

15. Perform a serviceability check to t he transmission and freew heel assembly (BHT206L4-MM, Chapter 63).

16. Make an entry in the helicopter Technica l Records to show that PART II of this Alert Service Bulletin is completed.

PART III: For helicopters exclusively used for training, for freewheel assemblies with an average of 3 engine start cy cles or more per hour, or if the freewheel has to be removed for any reason.

1. Remove freewheel assembly (BHT-206L4-MM-6, Chapter 63).

-NOTEIt is not necessary to remove wear sleeves from the forward and aft adapters unless they are damaged.

2. Disassemble the freewheel asse mbly (BHT-206L-CR&O, Chapter 63).

3. Discard the sprag and retainer (7, Figure 2), the output shaft ( 10), and the aft seal (3).

4. Visually inspect the re maining freewheel part details for condition (BHT-206LCR&O, Chapter 63).

5. Select from the following list, t he rework option deemed most suitable for

convenience:ASB 206L-04-129 Page 9 of 13

a. Order a replacement cap ass e mbly through your Bell Helic opter Spar es supplier. Please note that limited assets are available to support this bulletin, and spares will be iss u ed on a first come, first served basis.

b. Locally rework the aft bear ing cap as shown in Figure 3. Use a vibrating stylus to identify locally-reworked cap assembly by adding letter "R" to the s e rial number on the cap.

c. Provide the cap for rework to Bell Tennes see. This option per m its the original cap to be reworked by Bell T ennesee, id entified with the rewo rk letter "R" suffix to the serial number, and returned for installation.

d. Obtain a reworked cap from the rotable pool availabl e through Bell Tennessee. This option will accept the rework candidat e in exchange for a r e worked item from the rotable pool. Pl ease note that for this opt ion due to limit ed assets, a

rework candidate mus t be supplied in adv ance of shipment from the rotable pool.

e. For option c or d above, contact Bell Tennesee for advance scheduling at:

Bell Helicopter Tennessee Textr on 157 Industrial Park Road Piney Flats, TN. 37686

Office: 423-538-5114

Fax: 423-538-6198

6. Assemble the freewheel asse mbly (BHT-206L-CR&O, Chapter 63).

7. Install the freewheel assemb ly (BHT-206L4- MM-6, Chapter 63).

8. Make and entry in the he licopter Technical Records to show that PART III of the Alert Service Bulletin has been completed.

PART IV: For freew h eel assembl y equi pp ed w i th affected aft cap.

-NOTESprag and retainer and the output shaft presently inst alled on freewheel affected by this bulletin, whic h have not run with a defective cap, may remai n in service.

1. For freewheel assem b ly equipped with t he aft cap described in the HELICOPTER AFFECTED section of this bulletin, proceed as follow: AASB 206L-04-129 Page 10 of 13

A a. If the freewheel ass e mbly is c u rrently located in s pare st ock, continue with step 3.

b. If the freewheel ass e mbly has had PART II of this bulletin complied with, continue with step 2.

c. If the free wheel assemb ly has had PART III of this bulletin complied with, continue with step 8.

2. Remove freewheel assembly (BHT-206L4- MM-6, Chapter 63).

3. Disassemble the freewheel asse mbly (BHT-206L-CR&O, Chapter 63).

4. Discard the sprag and retainer (7, Figure 2) and the output shaft (10).

5. Visually inspect the re maining freewheel part details for condition (BHT- 206LCR&O, Chapter 63).

6. Assemble the freewheel asse mbly (BHT-206L-CR&O, Chapter 63).

7. Install the freewheel assemb ly (BHT-206L4- MM-6, Chapter 63).

8. Make and entry in the helic opter Technica l Records to show that PART IV of the Alert Service Bulletin has been completed.ASB 206L-04-129 Page 11 of 13

Figure 1. Location of the lubrica t ion channel and the serial numberASB 206L-04-129 Page 12 of 13

Figure 2. P a rts affected b y the missing lubrication c h annelASB 206L-04-129 Page 13 of 13

Figure 3. Instructions required to modi fy the aft bearing cap 406-040-509-101