### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Number: 777-78-0051**  Original Issue: October 23, 2003 Revision 3: August 23, 2012 ATA System: 7811 **SUBJECT:** EXHAUST (TRENT 800 Series Engines) - Collector/Nozzle - Turbine Exhaust Plug Assembly - Inspection and Retrofit Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET Copyright © 2003 Boeing. Unpublished Work. All Rights Reserved. Treatment of this document and its content is governed by contract with Boeing. Rights to use this document are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The Boeing Company. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, DreamlinerTM, BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing. BOEING is a trademark of Boeing Management Company.

Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 1 of 63 3.0Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 2 of 63 **BOEING SERVICE BULLETIN 777-78-0051**

BLANK PAGE**Table of Contents** Revision Transmittal Sheet............................................ 5 Summary...................................................... 9 1. PLANNING INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 A. Effectivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1. Airplanes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2. Spares Affected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 C. Reason. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 D. Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 F. Approval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 G. Manpower. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 1. Existing Data:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2. Data Supplied with this Service Bulletin:. . . . . . . . . . . . . . . . . . . . . . . . . . . 25 3. Installation Drawings Used in the Preparation of this Service Bulletin:. . . . . . . . . . . 25 K. Publications Affected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 26 M. Software Accomplishment Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 B. Industry Support Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 C. Parts Necessary for Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 1. Kits/Parts:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 2. Parts and Materials Supplied by the Operator:. . . . . . . . . . . . . . . . . . . . . . . . 28 3. Parts Modified and Reidentified:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4. Parts Removed and Not Replaced:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 31 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 A. GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 FIGURE 1: TURBINE EXHAUST PLUG ASSEMBLY - NUTPLATE REMOVAL AND HOLE INSPECTION PREPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 FIGURE 2: TURBINE EXHAUST PLUG ASSEMBLY HOLES - GENERAL VISUAL INSPECTION . . 41 FIGURE 3: IDENTIFICATION TAG - DEEP ETCH MARK. . . . . . . . . . . . . . . . . . . . . . . . 42 FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS. . . . . . . . . . . . . . . . . . . . . . . . . 43 FIGURE 5: TURBINE EXHAUST PLUG ASSEMBLY BOLTS - GENERAL VISUAL INSPECTION [Group 1, Configuration 2-3]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 FIGURE 6: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS. . . . . . . . . . . . . . . . . . 51

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 3 of 63 **BOEING SERVICE BULLETIN 777-78-0051**FIGURE 7: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD PLUG, 1/4 INCH DIAMETER NUTPLATE REPLACEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 FIGURE 8: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD AND AFT PLUG IDENTIFICATION TAG REPLACEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 FIGURE 9: TURBINE EXHAUST PLUG ASSEMBLY - INSTALLATION . . . . . . . . . . . . . . . . 60 APPENDIX A: 'WEDGELOCK' FASTENER INSTALLATION PROCESS FOR THE REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS. . . . . . . . . . 62 APPENDIX B: 'WEDGELOCK' AND TEMPORARY FASTENER INSTALLATION PROCESS FOR THE REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 4 of 63 **BOEING SERVICE BULLETIN 777-78-0051**

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Revision Transmittal Sheet**  **Number: 777-78-0051** Original Issue: October 23, 2003 Revision 3: August 23, 2012 ATA System: 7811 **SUBJECT:** EXHAUST (TRENT 800 Series Engines) - Collector/Nozzle - Turbine Exhaust Plug Assembly - Inspection and Retrofit This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** More work is necessary on the airplane(s) changed in accordance with the Original Issue, Revision 1 or Revision 2 of this service bulletin. Airplanes identified as Group 1 Configuration 3, that have done Revision 1 or Revision 2 of this service bulletin, must do a general visual inspection of the fasteners that attach the forward and aft plugs of the turbine exhaust plug assembly together of each engine, to identify if 3/16 inch diameter and/or 1/4 inch diameter bolts are used and, if necessary, install a serviceable turbine exhaust plug assembly with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. Airplanes identified as Group 1 Configuration 2, that have done the Original Issue, but not Revision 1 or Revision 2 of this service bulletin, must do a general visual inspection of the fasteners that attach the forward and aft plugs of the turbine exhaust plug assembly together of each engine, to identify if 3/16 inch diameter and/or 1/4 inch diameter bolts are used and, if necessary, install a serviceable turbine exhaust plug assembly with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. Additionally, if only 1/4 inch diameter bolts are found installed at all 33 locations, it is recommended that the identification tag on each forward and aft plug of each turbine exhaust plug assembly of each engine is replaced with one that has the correct post service bulletin identity. **REASON FOR REVISION** This revision is sent because of misleading instructions in the Original Issue, Revision 1 and Revision 2 of this service bulletin. As a result, some airplanes could have turbine exhaust plug assemblies with a mix of 1/4 inch and 3/16 inch diameter bolts used to attach the forward and aft plugs together. After accomplishment of the change in this service bulletin only 1/4 inch diameter bolts are to be installed at all 33 locations of the forward and aft plug interface of each turbine exhaust plug assembly, which is the same as the latest production configuration. Also this revision corrects a post service bulletin identification relationship error for the forward and aft plug, where the instructions of the Original Issue, Revision 1 and Revision 2 of this service bulletin gave them the identification intended for the next higher assembly part number.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 5 of 63These sections are changed: – Summary Background paragraph and Paragraph 1.C., Reason: Changed to add more in-service data and correct the intent of this service bulletin to agree with the reason for this revision. Also Boeing Fleet Team Digest (FTD) reference is added. – Summary Action paragraph and Paragraph 1.D., Description: Changed to add applicability and the work necessary related to the reason for this revision. – Summary Effectivity paragraph: Changed to add spares affected reference. – Summary Compliance paragraph: Changed to refer to Paragraph 1.E., Compliance and FAA possible AD information added. – Summary Manpower paragraph: Changed to refer to Paragraph 1.G., Manpower. – Summary Material Information paragraph: Changed to refer to Paragraph 2.A., Material - Price and Availability. – Summary Illustration: Changed to add applicability and the work necessary related to the reason for this revision. – Paragraph 1.A.1., Airplanes: Note added related to the installation of spare turbine exhaust plugs – Paragraph 1.A.2., Spares Affected: Changed to add turbine exhaust plug assembly part numbers and Quick Engine Change (QEC) kits affected by this service bulletin. – Paragraph 1.E., Compliance: Changed to give the recommended compliance for the work necessary related to the reason for this revision. FAA possible AD information added. – Paragraph 1.G., Manpower: Changed to add estimates for Parts 1 thru 4 and for the forward plug nutplate replacement of the changed Paragraph 3.B., Work Instructions. – Paragraph 1.H., Weight and Balance: Data added. – Paragraph 1.J.1., Existing Data: FTD, AMM, Service Bulletin Index and Service Letter references added. SRM references corrected. Boeing Drawing reference deleted. – Paragraph 1.J.3., Installation Drawings Used in the Preparation of this Service Bulletin: Data added. – Paragraph 1.M., Software Accomplishment Summary: Section added. – Paragraph 2.A., Material - Price and Availability: ROLT data changed. – Paragraph 2.C., Kits/Parts: Existing part number data added. Invalid rivet part number MS20427-3M4 corrected to MS20427M3-4. – Paragraph 2.C.2., Parts and Material Supplied by the Operator: Changed to show parts and materials necessary for Component Work. – Paragraph 2.C.3., Parts Modified and Reidentified: Changed to give the corrected turbine exhaust plug assembly (or 'primary plug assembly') reidentification and to show other related part number data. – Paragraph 2.D., Parts Necessary to Change Spares: Added part and kit data for Component Work. – Paragraph 2.E., Special Tooling - Price and Availability: Added data for operator supplied special tools. – Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin: Added data that was incorrectly located in Paragraph 2.C.2., Parts and Materials Supplied by the Operator, of the Original Issue, Revision 1 and Revision 2 of this service bulletin. – Paragraph 3.A., General Information: Notes added and changed. – Paragraph 3.B., Work Instructions: Changed to add Parts 1 thru 4. – Figure 1 thru Figure 4: Changed related to Part 2 and 3. – Figure 5 thru Figure 9: Added related to Part 1, 2 and 4. – Appendix A and Appendix B: Added related to the installation of 'wedgelocks' and temporary fasteners in the turbine exhaust plug assembly. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 6 of 63 **BOEING SERVICE BULLETIN 777-78-0051 REVISION HISTORY**  October 23, 2003 Original Issue: December 15, 2005 Revision 1: February 18, 2010 Revision 2: August 23, 2012 Revision 3:

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 7 of 63 **BOEING SERVICE BULLETIN 777-78-0051**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 8 of 63 **BOEING SERVICE BULLETIN 777-78-0051**

BLANK PAGE

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Summary**  **Number: 777-78-0051** Original Issue: October 23, 2003 Revision 3: August 23, 2012 ATA System: 7811 **SUBJECT:** EXHAUST (TRENT 800 Series Engines) - Collector/Nozzle - Turbine Exhaust Plug Assembly - Inspection and Retrofit
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **CONCURRENT REQUIREMENTS**
None. **BACKGROUND** Accomplishment of this service bulletin will make sure the integrity of the interface is kept between the forward plug and the aft plug of the turbine exhaust plug assembly to prevent separation occurrences. The aft plug can come off during a separation occurrence which could result in a potential hazard to persons on the ground or damage to the airplane. Boeing has had three reports of in-flight separations of the aft plug from the forward plug, which are the two parts of the turbine exhaust plug assembly. Subsequent to the first report where the separation occurred during takeoff, an investigation showed that some of the interface bolts were found loose or missing. The turbine exhaust plug assembly was sent back to Boeing for analysis and it was found that the remaining bolts had less than the necessary minimum run-on torque value. It was also found that the operator of the analyzed turbine exhaust plug assembly had disassembled it a minimum of three times during maintenance actions. Repeated assembly and disassembly causes the locking property of the nut on the nutplates to wear out and subsequently let the bolts become loose or removed in-service. This service bulletin gives instructions to do a general visual inspection of the forward and aft plug interface fasteners and holes of the turbine exhaust plug assembly of each engine and install 1/4 inch diameter bolts at all 33 locations. Boeing Service Related Problem (SRP) 777-SRP-78-0071 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 777 FTD 78-01002 is related to this service bulletin. **ACTION (PRR 62039) Group 1, Configuration 1:**  **Part 1 - Turbine Exhaust Plug - Airplane Work** 1. Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 9 of 63**NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. **Group 1, Configuration 2-3: Part 1 - Turbine Exhaust Plug - Airplane Work**  1. Do a general visual inspection of the 33 bolt locations of the forward and aft plug interface of each turbine exhaust plug assembly of each engine. 2. If only 3/16 inch diameter bolts are found used, or if a mix of 3/16 inch and 1/4 inch diameter bolts are found used, install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 2 or 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. 3. For Group 1 Configuration 2 airplanes only, if only 1/4 inch diameter bolts are found installed at all 33 locations, reidentify turbine exhaust plug assembly in accordance with Part 4. **Part 2 - Replacement Of All Remaining 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-1; 314W5521-1**  1. Remove the nutplates of 3/16 inch diameter bolts from the forward plug holes that interface with the aft plug. 2. Do a general visual inspection of the 33 holes for damage. 3. Ream the damaged hole(s) to remove damage and/or increase the diameter of all 33 holes to 1/4 inch or all remaining 3/16 inch diameter holes to 1/4 inch. Install new nutplates for 1/4 inch diameter bolts at all 33 locations or at all remaining locations. 4. For each component identified with part number 314W5520-1, reidentify the turbine exhaust plug assembly in accordance with Part 4. 5. For each component identified with part number 314W5521-1, no turbine exhaust plug assembly reidentification is necessary. **Part 3 - Replacement Of All 33 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-15, -19; 314W5520-1; 314W5521-1**  1. Remove the nutplates of the 33 3/16 inch diameter bolts from the forward plug holes that interface with the aft plug. 2. Do a general visual inspection of the 33 holes for damage. 3. Ream the damaged hole(s) to remove damage and increase diameter of all 33 holes to 1/4 inch. Install new nutplates for 1/4 inch diameter bolts at all 33 locations.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 10 of 63 **BOEING SERVICE BULLETIN 777-78-0051**4. For each component identified with part number 314W5520-15, 19, part mark and install identification tags on the forward and aft plugs to reidentify the turbine exhaust plug assembly. 5. For each component identified with part number 314W5520-1, reidentify the turbine exhaust plug assembly in accordance with Part 4. 6. For each component identified with part number 314W5521-1, no turbine exhaust plug assembly reidentification is necessary. **Part 4 - Reidentification of the Turbine Exhaust Plug Assembly - Component Work: 314W5520-1** 1. Remove the tags that have an incorrect part number identification. 2. Deep etch mark replacement identification tags and install one on the forward and aft plug. **EFFECTIVITY** 777-200/300 airplanes powered by Rolls-Royce Trent 800 Series Engines. Refer to Paragraph 1.A.1., Airplanes, for the list of affected airplanes. Refer to Paragraph 1.A.2., Spares Affected for the list of affected components. **COMPLIANCE** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Refer to Paragraph 1.E., Compliance. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the inspection and/or repair procedures given in this service bulletin. **MANPOWER** Refer to Paragraph 1.G., Manpower. **MATERIAL INFORMATION** Boeing and Operator Supplied Kits/Parts. Refer to Paragraph 2.A., Material - Price and Availability.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 11 of 63 **BOEING SERVICE BULLETIN 777-78-0051**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 12 of 63 **BOEING SERVICE BULLETIN 777-78-0051**

### Commercial **Airplanes** 

# 777 Service Bulletin **SPECIAL ATTENTION Number: 777-78-0051**  Original Issue: October 23, 2003 Revision 3: August 23, 2012 ATA System: 7811 **SUBJECT:** EXHAUST (TRENT 800 Series Engines) - Collector/Nozzle - Turbine Exhaust Plug Assembly - Inspection and Retrofit
BOEING RECOMMENDS THAT EACH OPERATOR EXAMINE THIS SERVICE BULLETIN IMMEDIATELY. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes Refer to Service Bulletin Index D624W001 Part 3 for Airplane Variable Number, Line Number, and Serial Number data. This service bulletin is for the airplanes shown below. An equivalent change is on subsequent production airplanes. Refer to PRR 62039 for data about this change. **NOTE:** The airplanes shown below had the configuration of turbine exhaust plug assemblies described in this service bulletin on their engines at delivery. Installation of spare turbine exhaust plug assemblies since delivery could put this configuration on engines of airplanes not shown in the effectivity below. Check your records to make sure the change in accordance with this service bulletin is accomplished on applicable turbine exhaust plug assemblies.
**DESCRIPTION CONFIGURATION**  **GROUP** 777-200/300 airplanes powered by Trent 800 engines before line position 470. - 1
That have not done the Original Issue, Revision 1 or Revision 2 of this service bulletin 1
That have done the Original Issue, but not Revision 1 or Revision 2 of this service bulletin 2

That have done Revision 1 or Revision 2 of this service bulletin 3

Airplane Models:

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 13 of 63777-200, 777-300 **Group Variable Number**  1 WA001 1 WA086 - WA093 1 WA101 - WA104 1 WA196 - WA198 1 WB031 - WB046 1 WB101 - WB106 1 WB161 - WB175 1 WB181 - WB192 1 WB201 - WB214 1 WB231 - WB247 1 WB416 - WB437 1 WB446 - WB453 1 WB501 - WB509 1 WB601 - WB606 1 WB611 - WB618 1 WB631 - WB638 1 WB646 - WB649 1 WC051 - WC073 1 WC101 - WC104 2. Spares Affected Examine your Quick Engine Change (QEC) kits for parts or components changed as shown in this service bulletin. If any parts or components are found, refer to Paragraph 2.C., Parts Necessary for Each Airplane, for the recommended use.
**Serial Number or Dash Number**  **Part Number**
C0028, C0029, C0030, C0031, C0032, C0041, C0042, C0045, C5001, C0049, C0050 654W0003-62

C0001, C0002 654W0003-3 C0052 654W0003-46 C0034, C0035 654W0003-68 C0043 654W0003-73

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 14 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Serial Number or**  **Dash Number Part Number** 
C0003, C0004 654W0003-18 C0020 654W0003-37 C0051 654W0003-81 C0012 654W0003-30 C0013, C0014, C0015, C0016, C0017 654W0003-23
C0033 654W0003-24 C0005, C0006, C0007 654W0003-12 C0027 654W0003-55 C0036, C0039 654W0003-57 -3, -4 QECRR777 Examine your spares supply for the parts or components identified below. If any parts or components are found, refer to Paragraph 3.B., Work Instructions for the recommended action.
**Part Number** 314W5520-15 314W5520-19 314W5520-1 (a) (a) Existing part number 314W5520-1 could also exist because of the instructions in the Original Issue of this service bulletin. But part number 314W5520- 1 is incorrect as the post service bulletin identity. **B. Concurrent Requirements**
None. **C. Reason** Accomplishment of this service bulletin will make sure the integrity of the interface is kept between the forward plug and the aft plug of the turbine exhaust plug assembly to prevent separation occurrences. The aft plug can come off during a separation occurrence which could result in a potential hazard to persons on the ground or damage to the airplane.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 15 of 63 **BOEING SERVICE BULLETIN 777-78-0051**Boeing has had three reports of in-flight separations of the aft plug from the forward plug, which are the two parts of the turbine exhaust plug assembly. Subsequent to the first report where the separation occurred during takeoff, an investigation showed that some of the interface bolts were found loose or missing. The turbine exhaust plug assembly was sent back to Boeing for analysis and it was found that the remaining bolts had less than the necessary minimum run-on torque value. It was also found that the operator of the analyzed turbine exhaust plug assembly had disassembled it a minimum of three times during maintenance actions. Repeated assembly and disassembly causes the locking property of the nut on the nutplates to wear out and subsequently let the bolts become loose or removed in-service. This service bulletin gives instructions to do a general visual inspection of the forward and aft plug interface fasteners and holes of the turbine exhaust plug assembly of each engine and install 1/4 inch diameter bolts at all 33 locations. Boeing Service Related Problem (SRP) 777-SRP-78-0071 is related to this service bulletin. Boeing Fleet Team Digest (FTD) 777 FTD 78-01002 is related to this service bulletin. Revision 1 was sent to tell operators that the assembly number shown on the identification tag was incorrect in Figure 3. This revision changes the assembly number shown on the identity tag from 314W5520-1 to 314W5521-1. This revision also corrects the spelling of the word "Separate," on the identification tag, and in the table of Figure 3. Airplane WB510, line 470, was deleted from this service bulletin effectivity. It was included in error. Revision 2 was sent to change the classification of the service bulletin from Standard to Special Attention and to add a compliance recommendation. Revision 2 also corrected a typographical error, adds damage tolerance data and adds maintenance zone data. Revision 3 is sent because of misleading instructions in the Original Issue, Revision 1 and Revision 2 of this service bulletin. As a result, some airplanes could have turbine exhaust plug assemblies with a mix of 1/4 inch and 3/16 inch diameter bolts used to attach the forward and aft plugs together. After accomplishment of the change in this service bulletin only 1/4 inch diameter bolts are to be installed at all 33 locations of the forward and aft plug interface of each turbine exhaust plug assembly, which is the same as the latest production configuration. Also this revision corrects a post service bulletin identification relationship error for the forward and aft plug, where the instructions of the Original Issue, Revision 1 and Revision 2 of this service bulletin gave them the identification intended for the next higher assembly part number. **D. Description Group 1, Configuration 1:**  **Part 1 - Turbine Exhaust Plug - Airplane Work** 1. Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 16 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Group 1, Configuration 2-3:**  **Part 1 - Turbine Exhaust Plug - Airplane Work** 1. Do a general visual inspection of the 33 bolt locations of the forward and aft plug interface of each turbine exhaust plug assembly of each engine. 2. If only 3/16 inch diameter bolts are found used, or if a mix of 3/16 inch and 1/4 inch diameter bolts are found used, install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 2 or 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. 3. For Group 1 Configuration 2 airplanes only, if only 1/4 inch diameter bolts are found installed at all 33 locations, reidentify turbine exhaust plug assembly in accordance with Part 4. **Part 2 - Replacement Of All Remaining 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-1; 314W5521-1**  1. Remove the nutplates of 3/16 inch diameter bolts from the forward plug holes that interface with the aft plug. 2. Do a general visual inspection of the 33 holes for damage. 3. Ream the damaged hole(s) to remove damage and/or increase the diameter of all 33 holes to 1/4 inch or all remaining 3/16 inch diameter holes to 1/4 inch. Install new nutplates for 1/4 inch diameter bolts at all 33 locations or at all remaining locations. 4. For each component identified with part number 314W5520-1, reidentify the turbine exhaust plug assembly in accordance with Part 4. 5. For each component identified with part number 314W5521-1, no turbine exhaust plug assembly reidentification is necessary. **Part 3 - Replacement Of All 33 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-15, -19; 314W5520-1; 314W5521-1**  1. Remove the nutplates of the 33 3/16 inch diameter bolts from the forward plug holes that interface with the aft plug. 2. Do a general visual inspection of the 33 holes for damage. 3. Ream the damaged hole(s) to remove damage and increase diameter of all 33 holes to 1/4 inch. Install new nutplates for 1/4 inch diameter bolts at all 33 locations. 4. For each component identified with part number 314W5520-15, 19, part mark and install identification tags on the forward and aft plugs to reidentify the turbine exhaust plug assembly. 5. For each component identified with part number 314W5520-1, reidentify the turbine exhaust plug assembly in accordance with Part 4.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 17 of 63 **BOEING SERVICE BULLETIN 777-78-0051**6. For each component identified with part number 314W5521-1, no turbine exhaust plug assembly reidentification is necessary. **Part 4 - Reidentification of the Turbine Exhaust Plug Assembly - Component Work: 314W5520-1** 1. Remove the tags that have an incorrect part number identification. 2. Deep etch mark replacement identification tags and install one on the forward and aft plug. Revision 1 - More work was necessary on airplanes changed as shown in the initial release of this service bulletin. Identification tags with the incorrect assembly number should be corrected when manpower and facilities are available. Revision 2 - No more work was necessary on airplanes changed in accordance with Revision 1 of this service bulletin. Revision 3 - More work is necessary on the airplane(s) changed in accordance with the Original Issue, Revision 1 or Revision 2 of this service bulletin. – Airplanes identified as Group 1 Configuration 3, that have done Revision 1 or Revision 2 of this service bulletin, must do a general visual inspection of the fasteners that attach the forward and aft plugs of the turbine exhaust plug assembly together of each engine, to identify if 3/16 inch diameter and/or 1/4 inch diameter bolts are used and, if necessary, install a serviceable turbine exhaust plug assembly with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. – Airplanes identified as Group 1 Configuration 2, that have done the Original Issue, but not Revision 1 or Revision 2 of this service bulletin, must do a general visual inspection of the fasteners that attach the forward and aft plugs of the turbine exhaust plug assembly together of each engine, to identify if 3/16 inch diameter and/or 1/4 inch diameter bolts are used and, if necessary, install a serviceable turbine exhaust plug assembly with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface. Additionally, if only 1/4 inch diameter bolts are found installed at all 33 locations, it is recommended that the identification tag on each forward and aft plug of each turbine exhaust plug assembly of each engine is replaced with one that has the correct post service bulletin identity. The work in this service bulletin is done in the maintenance zone(s) given below.
**Affected Maintenance Zones Zone**  **Model** 419, 429 777-200, 777-300 **E. Compliance** The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin mandatory. Accomplish the required action(s), based on the applicable condition(s), in Table(s) 1 thru 3, in accordance with Paragraph 3. Accomplishment Instructions.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 18 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Group 1, Configuration 1:**  **Table 1: Turbine Exhaust Plug Assembly - Replacement Of All 33 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts**  **Repeat Interval (Not to Exceed)**  **Compliance Time Action**  **Condition**

- Within 60 months after the Revision3 date of this service bulletin.Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts atall 33 locations of the forward and aft plug interface in accordance withParagraph 3.B., Work Instructions, Part 1, Step 2.b. (a) All airplanes

(a) A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. **Group 1, Configuration 2: Table 2: Turbine Exhaust Plug Assembly - General Visual Inspection of Bolts**  **Repeat Interval (Not to Exceed)**  **Compliance Time Action**  **Condition**

- Within 60 months after the Revision3 date of this service bulletin.Do a general visual inspection of all 33 bolt locations of each turbine exhaust plug assembly inaccordance with Paragraph 3.B., Work Instructions, Part 1, Step 3., to identify if 3/16 inch and/or 1/4 inch diameters are used at the forward and aft plug interface. All Airplanes

- Before further flight.Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts atall 33 locations of the forward and aft plug interface in accordance withParagraph 3.B., Work Instructions, Part 1, Step 3.a.(2). (a) Only 3/16 inch diameter bolts are found used at all 33 locations of the forward and aft plug interface.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 19 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Group 1, Configuration 2:**  **Table 2: Turbine Exhaust Plug Assembly - General Visual Inspection of Bolts Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition** 

- Before further flight.Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts atall 33 locations of the forward and aft plug interface in accordance withParagraph 3.B., Work Instructions, Part 1, Step 3.b.(2). (b) A mix of 3/16 and 1/4 inch diameter bolts are found used at the 33 locations ofthe forward and aft plug interface.

- None. Reidentify the forwardand aft plug in accordance with Paragraph 3.B., Work Instructions, Part 4, Step 1 and 2. Only 1/4 inch diameter bolts are found installed at all 33 locations forward and aft plug interface. (a) A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. (b) A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 2, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 20 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Group 1, Configuration 3:**  **Table 3: Turbine Exhaust Plug Assembly - General Visual Inspection of Bolts Repeat Interval**  **(Not to Exceed) Compliance Time**  **Action Condition** 

- Within 60 months after the Revision3 date of this service bulletin.Do a general visual inspection all 33 bolt locations of each turbine exhaust plug assembly inaccordance with Paragraph 3.B., Work Instructions, Part 1, Step 3., to identify if 3/16 inch and/or 1/4 inch diameters are used at the forward and aft plug interface. All Airplanes

- Before further flight.Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts atall 33 locations of the forward and aft plug interface in accordance withParagraph 3.B., Work Instructions, Part 1, Step 3.a.(2). (a) Only 3/16 inch diameter bolts are found used at all 33 locations of the forward and aft plug interface.

- Before further flight.Install a serviceable turbine exhaust plug assembly on each engine with 1/4 inch diameter bolts atall 33 locations of the forward and aft plug interface in accordance withParagraph 3.B., Work Instructions, Part 1, Step 3.b.(2). (b) A mix of 3/16 and 1/4 inch diameter bolts are found used at the 33 locations ofthe forward and aft plug interface.

- - None. Only 1/4 inch diameter bolts are found installed at all 33 locations forward and aft plug interface. (a) A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. (b) A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 2, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 21 of 63 **BOEING SERVICE BULLETIN 777-78-0051 F. Approval**  This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. **G. Manpower** The tables below show an estimate of the task-hours necessary to do this service bulletin for each engine. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task-hour data if necessary. The estimate does not include lost time. These are some examples of lost time: — Time to adjust to the workplace — Time to schedule the work — Time to examine the work — Time to cure the materials — Time to make the parts — Time to find the tools. **Group 1, Configuration 1: Part 1 - Airplane Work**  **Elapsed Hours Task Hours**  **Number of Persons Task**  1.00 1.00 1 Deactivate Thrust Reverser 0.63 1.25 2 Remove Turbine Ex- haust Plug Assembly 0.63 1.25 2 FIGURE 9 (a) 1.00 1.00 1 Activate Thrust Re- verser 3.25 4.50 TOTAL FOR EACH ENGINE (a) This estimate does not include the time to replace nutplates in accordance with FIGURE 7, if necessary. **Group 1, Configuration 2-3: Part 1 - Airplane Work**  **Elapsed Hours Task Hours**  **Number of Persons Task**  1.00 1.00 1 Deactivate Thrust Reverser

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 22 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Group 1, Configuration 2-3:**  **Part 1 - Airplane Work Elapsed Hours**  **Task Hours Number of Persons**  **Task** 1.80 1.80 1 FIGURE 5 0.63 1.25 2 Remove Turbine Ex- haust Plug Assembly 0.63 1.25 2 FIGURE 9 (a) 1.00 1.00 1 Activate Thrust Re- verser 4.05 5.30 TOTAL FOR EACH ENGINE (a) This estimate does not include the time to replace nutplates in accordance with FIGURE 7, if necessary. **Part 2 - Component Work: 314W5520-1 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 4.00 8.00 2 FIGURE 1 1.80 1.80 1 FIGURE 2 2.35 4.70 2 FIGURE 6 (a) 0.25 0.25 1 FIGURE 3 0.60 0.60 1 FIGURE 8 9.00 15.35 TOTAL FOR EACH ENGINE (a) This estimate is the maximum time necessary, which assumes there is a minimum of 1 1/4 inch diameter bolt installed and the remaining 32 3/16 inch diameter bolts are to be replaced with 1/4 inch diameter bolts. **Part 2 - Component Work: 314W5521-1 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 4.00 8.00 2 FIGURE 1 1.80 1.80 1 FIGURE 2 2.35 4.70 2 FIGURE 6 (a) 8.15 14.50 TOTAL FOR EACH ENGINE (a) This estimate is the maximum time necessary, which assumes there is a minimum of 1 1/4 inch diameter bolt installed and the remaining 32 3/16 inch diameter bolts are to be replaced with 1/4 inch diameter bolts.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 23 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Part 3 - Component Work: 314W5520-15, -19**  **Elapsed Hours Task Hours**  **Number of Persons Task**  4.00 8.00 2 FIGURE 1 1.80 1.80 1 FIGURE 2 0.25 0.25 1 FIGURE 3 3.00 6.00 2 FIGURE 4 9.05 16.05 TOTAL FOR EACH ENGINE **Part 3 - Component Work: 314W5520-1; 314W5521-1 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 4.00 8.00 2 FIGURE 1 1.80 1.80 1 FIGURE 2 3.00 6.00 2 FIGURE 4 (a) 8.80 15.80 TOTAL FOR EACH ENGINE (a) The time to do this task will be less than the estimate values, as they include identification tag installation work which is not necessary in this task for turbine exhaust plug assemblies identified with part number 314W5520-1 and 314W5521-1. **Part 4 - Component Work: 314W5520-1 Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 FIGURE 3 0.60 0.60 1 FIGURE 8 0.85 0.85 TOTAL FOR EACH ENGINE **Turbine Exhaust Plug Assembly, Forward Plug Nutplate Replacement Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.20 0.20 1 FIGURE 7 0.20 0.20 TOTAL FOR EACH NUTPLATE

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 24 of 63 **BOEING SERVICE BULLETIN 777-78-0051 H. Weight and Balance Changes**  **Left and Right Engine Turbine Exhaust Plug Assemblies Changed to have All 1/4 Inch Diameter Bolts at their Forward and Aft Plug Interface**  **Change in Moment (Pound-Inches)**  **Change in Weight (Pounds)**  **Airplane** + 189.5 + 0.2 All
**I. Electrical Load Data** Not changed. **J. References** 1. Existing Data: a. Engineering Change Memo PRR 62039. b. Boeing Service Letter 777-SL-51-013. c. Boeing Service Related Problem (SRP) 777-SRP-78-0071. d. Service Bulletin Index D624W001. e. Boeing Standard Overhaul Practices Manual (SOPM) 20-10-07, 20-50-10. f. 777 Aircraft Maintenance Manual (AMM) 78-11-02, 78-31-00. g. 777 Fleet Team Digest (FTD) 777 FTD 78-01002. h. 777-200 Structural Repair Manual (SRM) 51-30-01, 51-40-02, 54-42-30. i. 777-300 Structural Repair Manual (SRM) 51-30-01, 51-40-02, 54-42-30. 2. Data Supplied with this Service Bulletin:
None. 3. Installation Drawings Used in the Preparation of this Service Bulletin:
**Title Drawing Number**  RR AFT EXHAUST PLUG ATTACHMENT INTERFACE, REPAIR AND RETROFIT 314W5521

The table above lists applicable drawings used to prepare this service bulletin. The drawings are not necessary to make the specified changes, and are not supplied with this service bulletin. The drawings may not be applicable to all airplane configurations or operators.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 25 of 63 **BOEING SERVICE BULLETIN 777-78-0051 K. Publications Affected**  1. Publications: **Chapter-Section Publication**  78-11 777 Illustrated Parts Catalog 78-11 Component Maintenance Manual 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin does not affect FCS, therefore DTIs are not necessary. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts. **M. Software Accomplishment Summary** Not affected.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 26 of 63 **BOEING SERVICE BULLETIN 777-78-0051 2. MATERIAL INFORMATION**  **A. Material - Price and Availability** Boeing can supply the kits shown in Paragraph 2.C., Parts Necessary for Each Airplane and Paragraph 2.D., Parts Necessary to Change Spares . Operators are encouraged to share schedule requirements with Boeing for incorporation of the service bulletin. The kits are subject to the terms and conditions of the Boeing standard purchase order acknowledgment. Prices are in United States Dollars. Terms: Net 30 days. Reference this service bulletin and submit your purchase order by one of these methods: 1. Order on-line via ATA Spec 2000 or The Boeing PART Page 2. Fax to (206) 662-7145 **REFER TO THE BOEING PART PAGE ON MYBOEINGFLEET.COM OR CONTACT FIRST RESPONDER AT FR@BOEING.COM FOR THE LATEST REORDER LEAD TIME (ROLT) AND PRICE INFORMATION** 
**Unit Price as of the Revision 02** **date of this Ser vice Bulletin (US**  **Dollars) ROLT as of the**  **Revision 03 date**

**of this Service Bulletin (Calendar**  **Days) Name**  **Kit Number**

$7,198 567 Top Kit - 777 Airplanes, Trent -800 Powered 005W3246-1 $3,599 553 Subkit, Engine 005W3246-2 **B. Industry Support Information** Boeing warranty remedies are not available for the inspection and/or repair procedures given in this service bulletin. **C. Parts Necessary for Each Airplane** 1. Kits/Parts: To get the kits/parts shown below, refer to Paragraph 2.A., Material - Price and Availability. **NOTE:** One top kit and the items shown in Paragraph 2.C.2., Parts and Materials Supplied by the Operator , as applicable, are necessary for each airplane. **Part 3 - Component Work: 314W5520-15, -19**
**Kit 005W3246 Notes**  **Existing Part Number**  **Name QTY**  **New Part Number -1**  **-2** Top Kit, Airplane

- . 005W3246-1 Subkit, Engine 2

- 005W3246-2

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 27 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Part 3 - Component Work: 314W5520-15, -19** 
**Kit 005W3246 Notes**  **Existing Part Number**  **Name QTY**  **New Part Number -1**  **-2** Identification Tag

. 2 314W5520-23 (a) Bolt

. 33 BACB30UU4-1 BACN11G3AE1F Nutplate, Self-Locking

. 33 BACN11G4DE1F (a) Rivet

. 66 MS20427M3-4 (a) Rivet

. 6 MS20615-4M3 (a) If grip length shown is not available at Boeing, fasteners supplied in kits may be one grip length longer than indicated. Also, if any fasteners part numbers listed are not available or have been superseded, substitute fasteners may be supplied in kits. 2. Parts and Materials Supplied by the Operator: The following parts or materials are necessary to do the change in this service bulletin. Parts and materials in the manuals given in Paragraph 1.J., References, can also be necessary. Examine operator part and material supply to make sure all necessary parts and materials are available. **Part 2 - Component Work: 314W5520-1; 314W5521-1**
**Notes Name**  **QTY Part Number /**  **Specification** Maximum quantity. Adjust as necessary. Nutplate, Self-Locking 64 BACN11G4DE1F Maximum quantity for two for each nutplate. Adjust as necessary. (a) Rivet 128 MS20427M3-4

Maximum quantity. Adjust as necessary. Bolt 64 BACB30UU4-1 (a) Refer to 777 Structural Repair Manual Chapter 51 for alternate fasteners. **Part 3 - Component Work: 314W5520-1**
**Notes Name**  **QTY Part Number /**  **Specification** Subkit, Engine 1 005W3246-2

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 28 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Part 3 - Component Work: 314W5521-1** 
**Notes Name**  **QTY Part Number /**  **Specification** Nutplate, Self-Locking 66 BACN11G4DE1F (a) Rivet 132 MS20427M3-4 Bolt 66 BACB30UU4-1 (a) Refer to 777 Structural Repair Manual Chapter 51 for alternate fasteners. **Part 4 - Component Work: 314W5520-1**
**Notes Name**  **QTY Part Number /**  **Specification** Identification Tag 4 314W5520-23 (a) Rivet 12 MS20615-4M3 (a) Refer to 777 Structural Repair Manual Chapter 51 for alternate fasteners.
3. Parts Modified and Reidentified: The parts shown below are changed as shown in this service bulletin. The quantity (QTY) is the number of parts changed on each airplane. Components or subassembly parts are indented. The quantity of the indented part is the number of parts used on the next higher assembly.
**Notes New Part Number**  **Name QTY**  **Existing Part Number**  Referred to as 'Turbine Exhaust Plug Assembly'. (a) (b) (c) (e) (f) 314W5521-1 Primary Plug Assy 2 314W5520-15 or 314W5520-19 314W5520-1 (a) (d)

- Aft Plug Assy 1 .314W5520-3 or 314W5520-20 (a) (d)

- Forward Plug Assy 1 .314W5520-16 or 314W5520-21 (a) Make the change in accordance with this service bulletin. (b) This is the part number after the change is done in accordance with this service bulletin. (c) This part is not used in production. (d) There is no equivalent Boeing part number for the changed part. (e) The equivalent production part number is 314W5520-22. (f) Existing part number 314W5520-1 could also exist because of the instructions in the Original Issue of this service bulletin. But part number 314W5520-1 is incorrect as the post service bulletin identity.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 29 of 63 **BOEING SERVICE BULLETIN 777-78-0051**4. Parts Removed and Not Replaced: None. **D. Parts Necessary to Change Spares** It is recommended that primary plug assemblies (or 'turbine exhaust plug' assemblies) held as spares are inspected in accordance with FIGURE 5 and if necessary change them in accordance with Paragraph 3.B., Work Instructions, Part 2, 3 or 4, as applicable. To get the kits shown below, for each turbine exhaust plug assembly, refer to Paragraph 2.A., Material - Price and Availability. **Part 2 - Component Work: 314W5520-1**
**QTY Name**  **Part Number** 2 Identification Tag 314W5520-23 32 (maximum) Nutplate, Self-Lock- ing BACN11G4DE1F 64 (maximum) Rivet MS20427M3-4 6 Rivet MS20615-4M3 32 (maximum) Bolt BACB30UU4-1 **Part 2 - Component Work: 314W5521-1**
**QTY Name**  **Part Number** 32 (maximum) Nutplate, Self-Lock- ing BACN11G4DE1F 64 (maximum) Rivet MS20427M3-4 32 (maximum) Bolt BACB30UU4-1 **Part 3 - Component Work: 314W5520-15, -19; 314W5520-1**
**QTY Name**  **Kit Number** 1 Subkit, Engine 005W3246-2 **Part 3 - Component Work: 314W5521-1**
**QTY Name**  **Part Number** 33 Nutplate, Self-Lock- ing BACN11G4DE1F

66 Rivet MS20427M3-4 33 Bolt BACB30UU4-1

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 30 of 63 **BOEING SERVICE BULLETIN 777-78-0051 Part 4 - Component Work: 314W5520-1** 
**QTY Name**  **Part Number** 2 Identification Tag 314W5520-23 6 Rivet MS20615-4M3 **E. Special Tooling - Price and Availability** The operator can supply the tools shown in Paragraph 2.F., Special Tooling Necessary to do this Service Bulletin. Tool price and supply data are not given. **F. Special Tooling Necessary to do this Service Bulletin** To get the tools shown below, refer to Paragraph 2.E., Special Tooling - Price and Availability. Maintenance and overhaul tools in the manuals shown in Paragraph 1.J., References, can also be necessary. Examine operator tool supply to make sure all necessary tools are available.
**Name Part Number**  Step Reamer ST1864R-2820-2550- 4-221-4-64-2-4, or equivalent (a) 3/16 inch diameter temporary fastener ST30-7216A-200- 216-1.0, or equivalent (b) 1/4 inch diameter temporary fastener ST30-7216A-200- 279-1.0, or equivalent (b) (a) Can be purchased from: Boeing, Spares Customer Support - MC 36-65, Boeing Spares Department, P.O.Box 3707, Seattle, WA 98124-2207, USA. (b) A quantity of 32 are necessary.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 31 of 63 **BOEING SERVICE BULLETIN 777-78-0051**Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 32 of 63 **BOEING SERVICE BULLETIN 777-78-0051**

BLANK PAGE**3. ACCOMPLISHMENT INSTRUCTIONS A. GENERAL INFORMATION**  **CAUTION:** KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. **NOTE:** 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. The work instructions are divided into Parts. Task Hours and Elapsed Hours for each Part are given in Paragraph 1.G., Manpower. You can do Part 1, 2, 3 and 4 independently. 4. Unless shown differently, these dimensions and tolerances are used: – Linear dimensions are in inches – Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or minus 0.03 inch – Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch – Angular tolerance is plus or minus 2 degrees – Hole dimensions for standard solid rivets and fasteners are in Structural Repair Manual (SRM) Chapter 51 – Torque limits to tighten nuts and bolts are in SRM Chapter 51 5. Use the approved fastener and process material substitutions in accordance with SRM Chapter 51. 6. If the length of any fastener specified in this service bulletin does not meet installation standards given in SRM Chapter 51, then a fastener of the same specification, or an approved substitute, with a length which meets the installation standards given in SRM Chapter 51 may be used. In addition, washers may be installed for fastener grip length in accordance with SRM Chapter 51. 7. A General Visual Inspection is defined as: A visual examination of an interior or exterior area, installation or assembly to detect obvious damage, failure or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight or drop-light and may require removal or opening of access panels or doors. Stands, ladders or platforms may be required to gain proximity to the area being checked. 8. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 33 of 63 **BOEING SERVICE BULLETIN 777-78-0051**9. Boeing Service Letter 777-SL-51-013, Damage Reporting and Repair Plan/Design Guidelines, is an acceptable procedure to request information from Boeing for additional structural repair instructions. The Service Letter describes what information must be provided to Boeing before a structural repair can be provided. 10. The instructions in Paragraph 3.B., Work Instructions and the figures can include operation of tools or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain data on versions of the tools or test equipment that you can use. It is permitted to use replaced tools. It is not permitted to use superseded tools. 11. If it is necessary to remove more parts for access, you can remove those parts. If you can get access without removing identified parts, it is not necessary to remove all of the identified parts. Jacking and shoring limitations must be observed. 12. Where the work instructions include installation of a kept part, a new or serviceable part with the same part number can be installed as an alternative to the kept part. **B. WORK INSTRUCTIONS Part 1 - Turbine Exhaust Plug - Airplane Work**  1. Deactivate the Thrust Reversers (T/R's) for ground maintenance. Refer to 777 AMM 78-31-00 as an accepted procedure.
2. **Group 1, Configuration 1:** a. Remove the turbine exhaust plug assembly from each engine. Refer to 777 AMM 78-11-02 as an accepted procedure. b. Install a serviceable turbine exhaust plug assembly, with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface, back on each engine in accordance with FIGURE 9. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. (1) If one or more of the 1/4 inch diameter bolts has a run-on torque value of less than 5.0 inch-pounds, replace the nutplate on the forward plug for each of the related bolt(s) in accordance with FIGURE 7.
3. **Group 1, Configuration 2-3:** At each engine, do a general visual inspection of the all of the 33 bolt locations at the forward and aft plug interface in accordance with FIGURE 5. a. Only 3/16 inch diameter bolts are found used at all 33 locations: (1) Remove the turbine exhaust plug assembly from each engine. Refer to 777 AMM 78-11-02 as an accepted procedure.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 34 of 63 **BOEING SERVICE BULLETIN 777-78-0051**(2) Install a serviceable turbine exhaust plug assembly, with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface, back on each engine in accordance with FIGURE 9. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 3, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. (a) If one or more of the 1/4 inch diameter bolts has a run-on torque value of less than 5.0 inch-pounds, replace the nutplate on the forward plug for each of the related bolt(s) in accordance with FIGURE 7. b. A mix of 3/16 inch diameter and 1/4 inch diameter bolts are found used at the 33 locations. (1) Remove the turbine exhaust plug assembly from each engine. Refer to 777 AMM 78-11-02 as an accepted procedure. (2) Install a serviceable turbine exhaust plug assembly, with 1/4 inch diameter bolts at all 33 locations of the forward and aft plug interface, back on each engine in accordance with FIGURE 9. **NOTE:** A serviceable turbine exhaust plug assembly can be one that is removed from the airplane and subsequently changed in accordance with Part 2, or it can be a spare turbine exhaust plug assembly that is changed in accordance with Part 2 or 3. Or it can be a new turbine exhaust plug assembly, with part number 314W5520-22. (a) If one or more of the 1/4 inch diameter bolts has a run-on torque value of less than 5.0 inch-pounds, replace the nutplate on the forward plug for each of the related bolt(s) in accordance with FIGURE 7. c. Only 1/4 inch diameter bolts are found installed at all 33 locations. (1) **Group 1, Configuration 2:** Reidentify the turbine exhaust plug assembly: (a) Remove the turbine exhaust plug assembly from each engine. Refer to 777 AMM 78-11-02 as an accepted procedure. (b) Do Part 4. (c) Install the turbine exhaust plug assembly with the reidentified forward and aft plugs back on each engine in accordance with FIGURE 9. 1) If one or more of the 1/4 inch diameter bolts has a run-on torque value of less than 5.0 inch-pounds, replace the nutplate on the forward plug for each of the related bolt(s) in accordance with FIGURE 7. (2) **Group 1, Configuration 3:** No more work is necessary.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 35 of 63 **BOEING SERVICE BULLETIN 777-78-0051**4. If not done, activate the T/R's after ground maintenance. Refer to 777 AMM 78-31-00 as an accepted procedure. 5. Put the airplane back to a serviceable condition. **Part 2 - Replacement Of All Remaining 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-1; 314W5521-1**  1. As applicable: – Get each spare turbine exhaust plug assembly on which the description of Part 2 is necessary to be accomplished. – Get each removed turbine exhaust plug assembly for which the description of Part 2 is necessary to be accomplished. 2. Put and hold the forward plug vertically and remove all of the remaining 3/16 inch diameter nutplates from the holes that interface with the aft plug in accordance with FIGURE 1. 3. Do a general visual inspection of the holes, related to the removed 3/16 inch diameter nutplates, at the forward and aft plug interface in accordance with FIGURE 2. a. If a hole has damage that is more than the 0.2910 inch limit, contact Boeing for repair instructions. Refer to Boeing Service Letter 777-SL-51-013. 4. Install 1/4 inch diameter nutplates at all remaining hole locations where 3/16 inch diameter nutplates were removed in accordance with FIGURE 6. 5. For each component identified with part number 314W5520-1: a. Reidentify the turbine exhaust plug assembly in accordance with Part 4 6. For each component identified with part number 314W5521-1: a. No turbine exhaust plug assembly reidentification is necessary. **Part 3 - Replacement Of All 33 3/16 Inch Diameter Bolts With 1/4 Inch Diameter Bolts - Component Work: 314W5520-15, -19; 314W5520-1; 314W5521-1**  1. As applicable: – Get each spare turbine exhaust plug assembly on which the description of Part 3 is necessary to be accomplished. – Get each removed turbine exhaust plug assembly for which the description of Part 3 is necessary to be accomplished. 2. Put and hold the forward plug vertically and remove all of the 33 3/16 inch diameter nutplates from the holes that interface with the aft plug in accordance with FIGURE 1. 3. Do a general visual inspection of the holes, related to the removed 3/16 inch diameter nutplates, at the forward and aft plug interface in accordance with FIGURE 2. a. If a hole has damage that is more than the 0.2910 inch limit, contact Boeing for repair instructions. Refer to Boeing Service Letter 777-SL-51-013.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 36 of 63 **BOEING SERVICE BULLETIN 777-78-0051**4. For each component identified with part number 314W5520-15, -19: a. Deep etch mark the new identification tags for the forward and aft plugs in accordance with FIGURE 3. b. Install 1/4 inch diameter nutplates at all 33 hole locations and reidentify the turbine exhaust plug assembly in accordance with FIGURE 4. 5. For each component identified with part number 314W5520-1: a. Install 1/4 inch diameter nutplates at all 33 hole locations in accordance with FIGURE 4. b. Reidentify the turbine exhaust plug assembly in accordance with Part 4. 6. For each component identified with part number 314W5521-1: a. Install 1/4 inch diameter nutplates at all 33 hole locations in accordance with FIGURE 4. b. No turbine exhaust plug assembly reidentification is necessary. **Part 4 - Reidentification of the Turbine Exhaust Plug Assembly - Component Work: 314W5520-1** 1. Deep etch mark the replacement identification tags for the forward and aft plugs in accordance with FIGURE 3. 2. Remove the incorrectly identified identification tags and install the replacement identification tags for the forward and aft plugs in accordance with FIGURE 8.

Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3: August 23, 2012 37 of 63 **BOEING SERVICE BULLETIN 777-78-0051 FIGURE 1: TURBINE EXHAUST PLUG ASSEMBLY - NUTPLATE REMOVAL AND HOLE INSPECTION**  **PREPARATION (SHEET 1 OF 3)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 38 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.
**More Data Qty**  **Identification Name**  **Task Step**  (a) (c)

- - RIVET Remove 1 (b)

- BACN11G3AE1F NUTPLATE Remove

**FIGURE 1: TURBINE EXHAUST PLUG ASSEMBLY - NUTPLATE REMOVAL AND HOLE INSPECTION PREPARATION**  **(SHEET 2 OF 3)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 39 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** on the aft plug. 1 314W5520-16 OR 314W5520-21 FORWARD PLUG Put / Hold 2 on the forward plug. 1 314W5520-3 OR 314W5520-20 AFT PLUG Put / Hold of each plug. 33

- HOLE Align 3 (a) Quantity 66, if each turbine exhaust plug assembly is to have all 33 3/16 inch diameter bolts replaced with 1/4 inch diameter bolts. Or, quantity as necessary, for each turbine exhaust plug assembly that is to have all remaining locations that have 3/16 inch diameter bolts replaced with 1/4 inch diameter bolts. Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51-40-02 an accepted procedure. (b) Quantity 33, if each turbine exhaust plug assembly is to have all 33 3/16 inch diameter bolts replaced with 1/4 inch diameter bolts. Or, quantity as necessary, for each turbine exhaust plug assembly that is to have all remaining locations that have 3/16 inch diameter bolts replaced with 1/4 inch diameter bolts. (c) Be careful during the removal of rivets to minimize damage to the holes.

**FIGURE 1: TURBINE EXHAUST PLUG ASSEMBLY - NUTPLATE REMOVAL AND HOLE INSPECTION PREPARATION**  **(SHEET 3 OF 3)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 40 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.
**More Data Qty**  **Identification Name**  **Task Step**  (a)

- - HOLE Inspect 1 (a) by general visual inspection, at the 33 locations of the forward plug and aft plug interface, for wear damage and/or hole elongation, for each turbine exhaust plug assembly that is to have all 33 3/16 inch diameter bolts replaced. Or, by general visual inspection, at each 3/16 inch diameter bolt location, at the forward plug and aft plug interface, for wear damage and/or hole elongation, for each turbine exhaust plug assembly that is to have all remaining locations that have 3/16 inch diameter bolts replaced with 1/4 inch diameter bolts.

**FIGURE 2: TURBINE EXHAUST PLUG ASSEMBLY HOLES - GENERAL VISUAL INSPECTION (SHEET 1 OF 1)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 41 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.
**More Data Qty**  **Identification Name**  **Task Step**  with the text as follows, for the forward and aft plug: Assy 314W5521-1; MATCHED SET. DO NOT SEPARATE; S/N: XXX-XXXX. Refer to SOPM 20-50-10 as an accepted procedure. (a) (b) 2 314W5520-23 IDENTIFICATION TAG Identify 1

(a) The serial number code is to be operator defined. A unique serial number is necessary for each matched set of forward and aft plugs (turbine exhaust plug assembly) to help the operator keep the hardware as a matched set. EXAMPLE: S/N TBC-0001. (b) The serial number is recommended to be on one half of the identification tag and one-quarter inch (24 point) in height. The remaining text is recommended to be on the other half of the identification tag and 12 point in height. The text is recommended to be centered to keep a minimum 2D distance from each of the rivets after installation.

**FIGURE 3: IDENTIFICATION TAG - DEEP ETCH MARK (SHEET 1 OF 1)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 42 of 63 **BOEING SERVICE BULLETIN 777-78-0051 FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER**  **BOLTS WITH 1/4 INCH DIAMETER BOLTS (SHEET 1 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 43 of 63 **BOEING SERVICE BULLETIN 777-78-0051 FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER**  **BOLTS WITH 1/4 INCH DIAMETER BOLTS (SHEET 2 OF 6)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 44 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.

**FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 3 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 45 of 63 **BOEING SERVICE BULLETIN 777-78-0051 NOTE:**  If this Figure is used for a turbine exhaust plug assembly identified with part number 314W5520-1 or 314W5521-1, Steps 8 thru 11 are not necessary.
**More Data Qty**  **Identification Name**  **Task Step**  in the interface holes of the aft plug and the forward plug. (a) 5 ST30-7216A-200-216- 1.0 ('WEDGELOCK') OR EQUIVALENT3/16 INCH DIA FASTENER Install (Temporary) 1

**WARNING:** USE CARE WHEN DRILLING IN TITANIUM. SMALL PARTICLES AND FINE SHAVINGS OF TITANIUM ARE HIGHLY FLAMMABLE. WATER WITH HOT TITANIUM CAN CAUSE A STEAM EXPLOSION. EXTINGUISH ALL FIRES OF TITANIUM WITH FULLY DRY TALC, CALCIUM CARBONATE, SAND, OR GRAPHITE. APPLY THE POWDER TO A DEPTH OF ONE-HALF INCH OR MORE OVER THE BURNING METAL. DO NOT USE FOAM, WATER, CARBON TETRACHLORIDE, OR CARBON DIOXIDE. IF YOU DO NOT OBEY, YOU CAN CAUSE INJURY TO PERSONS.
to 1/4 inch diameter, Class III hole. Use Step Reamer partnumber ST1864R2820-2550-4-221-4-64-2-4, or equivalent, between thefirst and fifth 'wedgelocks' to remove damage up to therepair limit, or to increase its diameter to 1/4 inch. (c) 1

- HOLE Ream 2

that was reamed, bygeneral visual inspection, to make sure there is no damage. 1

- HOLE Inspect 3

into the repaired or increased diameter hole. (a) 1 ST30-7216A-200-279- 1.0 ('WEDGELOCK') OR EQUIVALENT1/4 INCH DIA FASTENER Install (Temporary) 4

that were temporarily installed. (a) 5 ST30-7216A-200-216- 1.0 ('WEDGELOCK') OR EQUIVALENT3/16 INCH DIA FASTENER Remove / Keep 5

that were temporarily installed. 32 ST30-7216A-200-279- 1.0 ('WEDGELOCK') OR EQUIVALENT1/4 INCH DIA FASTENER Remove 6

1 314W5520-3 OR 314W5520-20 AFT PLUG Remove / Keep

**FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 4 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 46 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** on the inner circumference of the forward plug using the existing rivet holes. 33 BACN11G4DE1F NUTPLATE Install (New) 7

(d) 66 MS20427M3-4 RIVET Install (New) **CAUTION:** ADJUST THE IDENTIFICATION TAG POSITIONS TO AVOID DRILLING HOLES WITHIN 0.31 INCHES OF A WELD CENTERLINE

identified for the forward plug. (b) 1 314W5520-23 IDENTIFICATION TAG Put / Hold 8

0.124 - 0.128 inch diameter. (c) 3

- HOLE Drill / Ream

identified for the forward plug. 1 314W5520-23 IDENTIFICATION TAG Install (New) 9 (d) 3 MS20615-4M3 RIVET Install (New) identified for the aft plug. (b) 1 314W5520-23 IDENTIFICATION TAG Put / Hold 10

0.124 - 0.128 inch diameter. (c) 3

- HOLE Drill / Ream

identified for the aft plug. 1 314W5520-23 IDENTIFICATION TAG Install (New) 11 (d) 3 MS20615-4M3 RIVET Install (New) (a) Do not install the 'wedgelocks' (or equivalent 3/16 inch diameter temporary fasteners) in a continuous sequence. Install the first 'wedgelock' in the hole located sequentially next to the hole that is found to have the largest damage. Install the second 'wedgelock' in the hole nearest to the circumferential opposite of the first 'wedgelock' installed. Install the third 'wedgelock' in the hole nearest to the circumferential midpointbetween the first and second 'wedgelocks'. Install the fourth 'wedgelock' in the hole nearest to the circumferential opposite as the third installed 'wedgelock'. Install the fifth 'wedgelock' in the hole located sequentially next to the hole that to has the largest damage. After the hole is reamed and no damage is found, install a 1/4 inch 'wedgelock' in the repaired or increased diameter hole. Move the first thru fifth 'wedgelocks' clockwise or counter-clockwise to repair the hole with the next largest damage, until 5 3/16 inch diameter 'wedgelocks' cannot be installed because 1/4 inch diameter 'wedgelocks' are installed. Do steps 1 thru 5 again to repeat this process until 32 holes are filled with 1/4 inch 'wedgelocks' and all of the 33 holes are repaired and/or increased to 1/4 inch diameter. Refer to APPENDIX A for a graphical example of the 'wedgelock' installation process. (b) The identification tag is to be positioned on the side of the stringer where the distance between the stringer and the skin chem-milled area is maximum, but with the minimum conditions that there is a 2D edgemargin between the rivets and the edges of the identification tag and that there is a 2D edge margin between the rivets and the chemically milled area. Refer to 777-200 SRM 54-42-30 or 777-300 SRM 54-42- 30 for turbine exhaust plug assembly details.

**FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 5 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 47 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** (c) Refer to SOPM 20-10-07 and 777-200 SRM 51-30-01 or 777-300 SRM 51-30-01 Section 5, as an accepted procedure, to drill or ream titanium. (d) Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51-40-02 as an accepted procedure.

**FIGURE 4: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL 33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 6 OF 6)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 48 of 63 **BOEING SERVICE BULLETIN 777-78-0051 This Figure applies only to: Group 1, Configuration 2-3.** 

**FIGURE 5: TURBINE EXHAUST PLUG ASSEMBLY BOLTS - GENERAL VISUAL INSPECTION (SHEET 1 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 49 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each engine.
**More Data Qty**  **Identification Name**  **Task Step**  by general visual inspection, at the forward and aft plug interface, to find if 3/16 inch diameter bolts and/or 1/4 inch diameter bolts are used at the forwardand aft plug interface. 33 123423-3-1 OR BACB30UU4-1 BOLT Inspect 1

**FIGURE 5: TURBINE EXHAUST PLUG ASSEMBLY BOLTS - GENERAL VISUAL INSPECTION (SHEET 2 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 50 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.

**FIGURE 6: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 1 OF 4)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 51 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** Use 3/16 inch diameter fastener, ST30- 7216A-200-216-1.0 ('Wedgelock') orequivalent, in the interface holes of theaft plug and the forward plug, that do not have a nutplate.Or, use 1/4 inch diameter fasteners in the interface holes of the aft plug and the forward plug that have a nutplate. (a) 5
- FASTENER Install (Temporary) 1

**WARNING:** USE CARE WHEN DRILLING IN TITANIUM. SMALL PARTICLES AND FINE SHAVINGS OF TITANIUM ARE HIGHLY FLAMMABLE. WATER WITH HOT TITANIUM CAN CAUSE A STEAM EXPLOSION. EXTINGUISH ALL FIRES OF TITANIUM WITH FULLY DRY TALC, CALCIUM CARBONATE, SAND, OR GRAPHITE. APPLY THE POWDER TO A DEPTH OF ONE-HALF INCH OR MORE OVER THE BURNING METAL. DO NOT USE FOAM, WATER, CARBON TETRACHLORIDE, OR CARBON DIOXIDE. IF YOU DO NOT OBEY, YOU CAN CAUSE INJURY TO PERSONS.
to 1/4 inch diameter, Class III hole. Use Step Reamer partnumber ST1864R2820-2550-4-221-4-64-2-4, or equivalent, between thefirst and fifth 'wedgelocks', or first andfifth 1/4 inch diameter temporary fasteners, to remove damage up to the repair limit, or to increase its diameter to 1/4 inch. (b) 1

- HOLE Ream 2

by general visual inspection, to make sure there is no damage. 1

- HOLE Inspect 3

into the repaired or increased diameter hole. (a) 1 ST30-7216A-200-279- 1.0 ('WEDGELOCK') OR EQUIVALENT1/4 INCH DIA FASTENER Install (Temporary) 4

**FIGURE 6: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 2 OF 4)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 52 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** 3/16 inch diameter fasteners, ST30- 7216A-200-216-1.0 ('Wedgelock') or equivalent, that were temporarily installed.Or, 1/4 inch diameter fasteners thatwere temporarily installed. (a) 5
- FASTENER Remove / Keep 5

1/4 inch diameter fasteners, ST30- 7216A-200-279-1.0 ('Wedgelock') or equivalent, that were temporarily installed.Or, 1/4 inch diameter fasteners thatwere temporarily installed. 32

- FASTENER Remove 6

1 314W5520-3 OR 314W5520-20 AFT PLUG Remove / Keep as necessary, at all remaining locationsthat do not have nutplates for 1/4 inch diameter bolts, onthe inner circumference of the forwardplug, using the existing rivet holes. - BACN11G4DE1F NUTPLATE Install (New) 7

as necessary, two for each nutplate. (c) - MS20427M3-4 RIVET Install (New)

**FIGURE 6: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 3 OF 4)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 53 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** (a) Do not install the 'wedgelocks' (or equivalent 3/16 inch diameter temporary fasteners) or temporary 1/4inch diameter fasteners in a continuous sequence. Install the first 'wedgelock', in the hole located sequentially next to the hole that is found to have the largest damage or that is remaining at 3/16 inch diameter, or install the first temporary fastener in the equivalently located 1/4 inch diameter hole. Install the second 'wedgelock' in the hole nearest to the circumferential opposite of the first 'wedgelock' installed, or install the second temporary fastener in the equivalently located 1/4 inch diameter hole. Install the third 'wedgelock' in the hole nearest to the circumferential midpoint between the first and second 'wedgelocks', or install the third temporary fastener in the equivalently located 1/4 inch diameter hole. Install the fourth 'wedgelock' in the hole nearest to the circumferential opposite as the third installed 'wedgelock', or install the fourth temporary fastener in the equivalently located 1/4 inch diameter hole. Install the fifth 'wedgelock' in the hole located sequentially next to the hole that to has the largest damage, or install the fifth temporary fastener in the equivalently located 1/4 inch diameter hole. After the hole is reamed and no damage is found, install a 1/4 inch 'wedgelock' in the repaired or increased diameter hole. Move the first thru fifth 'wedgelocks', or the first thru fifth 1/4 inch diameter temporary fasteners clockwise or counter-clockwise to repair the hole with the next largest damage and/or increase its diameter to 1/4 inch, until 5 'wedgelocks' cannot be installed because 1/4 inch diameter wedgelocks or 1/4 inch diameter temporary fasteners areinstalled. Do steps 1 thru 5 again to repeat this process until 32 fastener holes are filled with 1/4 inch diameter 'wedgelocks' or 1/4 inch diameter temporary fasteners and all of the 33 fastener holes are repaired and/or increased to 1/4 inch diameter. Refer to APPENDIX B for a graphical example of the 'wedgelock' and/or temporary fastener installation process. (b) Refer to SOPM 20-10-07 and 777-200 SRM 51-30-01 or 777-300 SRM 51-30-01 Section 5, as an accepted procedure, to drill or ream titanium. (c) Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51-40-02 as an accepted procedure.

**FIGURE 6: TURBINE EXHAUST PLUG ASSEMBLY - REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS**  **(SHEET 4 OF 4)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 54 of 63 **BOEING SERVICE BULLETIN 777-78-0051 FIGURE 7: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD PLUG, 1/4 INCH DIAMETER NUTPLATE**  **REPLACEMENT (SHEET 1 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 55 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each nut plate location of a turbine exhaust plug assembly.
**More Data Qty**  **Identification Name**  **Task Step**  Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51-40-02 as an accepted procedure. 2 MS20427M3-4 RIVET Remove 1

1 BACN11G4DE1F NUTPLATE Remove 1 BACN11G4DE1F NUTPLATE Install (New) 2 Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51-40-02 as an accepted procedure. 2 MS20427M3-4 RIVET Install (New)

**FIGURE 7: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD PLUG, 1/4 INCH DIAMETER NUTPLATE REPLACEMENT**  **(SHEET 2 OF 2)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 56 of 63 **BOEING SERVICE BULLETIN 777-78-0051 FIGURE 8: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD AND AFT PLUG IDENTIFICATION TAG**  **REPLACEMENT (SHEET 1 OF 3)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 57 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each turbine exhaust plug assembly.

**FIGURE 8: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD AND AFT PLUG IDENTIFICATION TAG REPLACEMENT**  **(SHEET 2 OF 3)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 58 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** Refer to 777-200 SRM 51-40-02 or 777-300 SRM 51- 40-02 an accepted procedure. 6 MS20615-4M3 RIVET Remove 1

that were incorrectly identified with 'Assy 314W5520-1'. 2 314W5520-23 IDENTIFICATION TAG Remove

one on the forward plug and one on the aft plug. (a) 2 314W5520-23 IDENTIFICATION TAG Install (New) 2

three for each identification tag. Refer to 777-200 SRM 51- 40-02 or 777-300 SRM 51-40-02 an accepted procedure. (a) 6 MS20615-4M3 RIVET Install (New)

(a) Make sure the identification tag is located on the side of the stringer where the distance between the stringer and the skin chem-milled area is maximum, but with the minimum conditions that there is a 2D edge margin between the rivets and the edges of the identification tag and that there is a 2D edge margin between the rivets and the chemically milled area.

**FIGURE 8: TURBINE EXHAUST PLUG ASSEMBLY - FORWARD AND AFT PLUG IDENTIFICATION TAG REPLACEMENT**  **(SHEET 3 OF 3)**
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 59 of 63 **BOEING SERVICE BULLETIN 777-78-0051**The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY numbers shown below are the number of parts necessary for each engine.

**FIGURE 9: TURBINE EXHAUST PLUG ASSEMBLY - INSTALLATION (SHEET 1 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 60 of 63 **BOEING SERVICE BULLETIN 777-78-0051 More Data**  **Qty Identification**  **Name Task**  **Step** (b) 1

- FORWARD PLUG Install (Changed) 1 (a) (b) 1

- AFT PLUG Install (Changed) If applicable. (a) 1 314W5520-22 TURBINE EXHAUST PLUG ASSEMBLY Install (New) If applicable. (a) 33 BACB30UU4-1 BOLT Install (New) If applicable. (a) 33 BACB30UU4-1 BOLT Install (Kept) 73 - 83 inch-pounds. 33 BACB30UU4-1 BOLT Torque (a) Refer to 777 AMM 78-11-02 as an accepted procedure. During the installation, make sure there is 5.0 inch-pounds or more of run-on torque for each of the bolts related to nutplates of the forward plug, at the forward and aft plug interface. (b) Together the installation of these changed parts relates to the installation of the changed turbine exhaust plug assembly part number 314W5521-1. Refer to Paragraph 2.C.3., Parts Modified and Reidentified.

**FIGURE 9: TURBINE EXHAUST PLUG ASSEMBLY - INSTALLATION (SHEET 2 OF 2)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 61 of 63 **BOEING SERVICE BULLETIN 777-78-0051 APPENDIX A: 'WEDGELOCK' FASTENER INSTALLATION PROCESS FOR THE REPLACEMENT OF ALL**  **33 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS (SHEET 1 OF 1)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 62 of 63 **BOEING SERVICE BULLETIN 777-78-0051 APPENDIX B: 'WEDGELOCK' AND TEMPORARY FASTENER INSTALLATION PROCESS FOR THE**  **REPLACEMENT OF ALL REMAINING 3/16 INCH DIAMETER BOLTS WITH 1/4 INCH DIAMETER BOLTS (SHEET 1 OF 1)** 
Export Controlled ECCN: 9E991 - BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: October 23, 2003 777-78-0051 Revision 3 August 23, 2012 63 of 63 **BOEING SERVICE BULLETIN 777-78-0051**