Service Bulletin B787-81205-SB710026-00 POWER PLANT - GEnx-1B,

Forward Engine Mount - Barrel Nut Change

Publication: B787-81205-SB710026-00 Issue 001, 10 Jun 2015

BOEING PROPRIETARY, CONFIDENTIAL AND/OR TRADE SECRET

Copyright © 2015 Boeing. Unpublished Work. All rights reserved.

Treatment of this data module and its content is governed by contract with Boeing. Rights to use this data module 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, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10,

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license is granted in connection with this document unless provided in writing by Boeing.

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Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 300-774). An export license

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has the individual responsibility to abide by all export laws.

ECCN: 9E991

The applicability information below is referenced at the lower left of each page to indicate the page applicability.

These references are valid for this print copy only.

PM Applicability (Publication Module applicability)

787-8 and 787-9 Airplanes equipped with General Electric GEnx-1B engines. Refer to Data Module SB

B787-A-71-00-0026-00A-932A-D, Paragraph 1., Effectivity for the list of affected airplanes.

TITLE PAGE B787-81205-SB710026-00

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6.0

B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Service Bulletin B787-81205-SB710026-00

Table of Contents

Page

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

PLANNING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

1. Effectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

A. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

B. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2. Concurrent Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

3. Reason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5. Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

6. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

8. Weight and Balance Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

9. Electrical Load Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

10. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

A. Existing Data: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

B. Data Supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . . 16

C.Installation Requirement Modules Used in the Preparation of this Service Bulletin: . . . 16

11. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

12. Interchangeability and Intermixability of Parts . . . . . . . . . . . . . . . . . . . . . . . . . 17

13. Software Accomplishment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

MATERIAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

1. Material - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2. Industry Support Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3. Parts Necessary for Each Airplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

A. Kits/Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

B. Parts and Materials Supplied by the Operator: . . . . . . . . . . . . . . . . . . . . . . . 20

C. Parts Modified and Reidentified: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

D. Parts Removed and Not Replaced: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

4. Parts Necessary to Change Spares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5. Special Tooling - Price and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6. Special Tooling Necessary to do this Service Bulletin . . . . . . . . . . . . . . . . . . . . . 21

ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

1. GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Task 1 – FORWARD ENGINE MOUNT BARREL NUT REPLACEMENT [Group 1: ]. . . . . . . . . . . . 29

Appendix A – PART DEMAND INTENT [Group 1: ]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

TABLE OF CONTENTS B787-81205-SB710026-00

Issue 001, 10 Jun 2015

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Service Bulletin B787-81205-SB710026-00

List of Illustrations

Description

Group 1-2:

Table 1 List of Illustrations - Service Bulletin B787-81205-SB710026-00

ICN Used In

ICN-B787-A-000061-A-81205-10382-A-01-1 B787-A-71-00-0026-00A-931C-D Issue 001

ICN-B787-A-000061-A-81205-10383-A-01-1 B787-A-71-00-0026-01A-933B-D Issue 001

ICN-B787-A-000061-A-81205-10384-A-01-1 B787-A-71-00-0026-01A-933B-D Issue 001

ICN-B787-A-000061-A-81205-10385-A-01-1 B787-A-71-00-0026-01A-933B-D Issue 001

ICN-B787-A-000061-A-81205-07008-A-01-1 B787-A-71-00-0026-0AA-931D-D Issue 001

Applicable To: B787-A-71-00-0026-00A-00AA-D

Model 787 End of data module Issue 001, 10 Jun 2015

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Service Bulletin B787-81205-SB710026-00

List of Effective Data Modules

Description

Group 1-2:

Table 1 List of Effective Data Modules - Service Bulletin B787-81205-SB710026-00

Data Module – Information Name Issue Issue Status Issue Date

B787-A-71-00-0026-00A-00AA-D – List of Illustrations 001 New 2015-06-10

B787-A-71-00-0026-00A-00SA-D – List of Effective Data Modules 001 New 2015-06-10

B787-A-71-00-0026-00A-931C-D – Summary 001 New 2015-06-10

B787-A-71-00-0026-00A-932A-D – PLANNING INFORMATION 001 New 2015-06-10

B787-A-71-00-0026-00A-934A-D – MATERIAL INFORMATION 001 New 2015-06-10

B787-A-71-00-0026-00A-933A-D – ACCOMPLISHMENT INSTRUCTIONS 001 New 2015-06-10

B787-A-71-00-0026-01A-933B-D – Task 1 – FORWARD ENGINE MOUNT 001 New 2015-06-10

BARREL NUT REPLACEMENT [Group 1: ]

B787-A-71-00-0026-0AA-931D-D – Appendix A – PART DEMAND INTENT 001 New 2015-06-10

[Group 1: ]

Applicable To: B787-A-71-00-0026-00A-00SA-D

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Service Bulletin B787-81205-SB710026-00

Summary

References

Reference Title

SB B787-A-71-00-0026-00A-932A-D Issue 001, Spares Affected

Paragraph 1.B.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Compliance

Paragraph 5.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Weight and Balance Changes

Paragraph 8.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Electrical Load Data

Paragraph 9.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Publications Affected

Paragraph 11.

SB B787-A-71-00-0026-00A-934A-D Issue 001, Kits/Parts

Paragraph 3.A.

SB B787-A-71-00-0026-00A-934A-D Issue 001, Parts and Materials Supplied by the Operator

Paragraph 3.B.

SB B787-A-71-00-0026-00A-934A-D Issue 001, Special Tooling Necessary to do this Service Bulletin

Paragraph 6.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Effectivity

Paragraph 1.

SB B787-A-71-00-0026-00A-934A-D Issue 001, Industry Support Information

Paragraph 2.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Manpower

Paragraph 7.

SB B787-A-71-00-0026-00A-934A-D Issue 001, Material - Price and Availability

Paragraph 1.

Service Bulletin

B787-81205-SB710026-00 – Appendix A – PART

DEMAND INTENT [Group 1: ]

SB B787-A-71-00-0026-0AA-931D-D Issue 001

Applicable To: B787-A-71-00-0026-00A-931C-D

Model 787 Issue 001, 10 Jun 2015

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Description

Group 1-2:

1. CONCURRENT REQUIREMENTS

None.

2. BACKGROUND

Accomplishment of this service bulletin will replace the barrel nuts on the forward engine mount. The forward

engine mount barrel nuts have been redesigned to reduce the likelihood of cracking. A crack on both sides

of the barrel nut could cause complete failure of the barrel nut. Complete failure of two or more barrel nuts

on the same engine reduces the load capacity of the forward engine mount and could result in possible

separation of an engine from the airplane during flight. Separation of an engine under power could result in

loss of control of the airplane.

An operator reported that while replacing the No. 2 engine on a 747-8 airplane, the Non Destructive Test

(NDT) inspection of the barrel nuts on the forward engine mount revealed cracks on two of the four barrel

nuts. The operator also discovered one cracked barrel nut on the No. 1 engine of the 747-8 airplane. This

was the first reported occurrence on the 747-8. The Boeing Company did a Non Destructive Test (NDT) inspection of barrel nuts on a flight test 747-8 airplane. There were two barrel nuts where a crack had initiated.

A service bulletin was issued to initiate inspections of the forward engine mount barrel nuts for the 747-8

fleet. Operators have reported three additional cracked barrel nuts on three separate airplanes since the

release of that service bulletin. These barrel nuts are located at the forward end of the strut box and are

used to fasten the forward engine mount to the strut. A barrel nut with a crack on one side will still be able

to carry ultimate load. A crack on both sides of the barrel nut could cause complete failure of the barrel nut.

Boeing has not received any reports of a barrel nut with a crack on both sides.

787 airplanes with General Electric (GE) engines have a similar forward engine mount configuration and

use the same barrel nut part number as the 747-8. Therefore, Boeing service bulletin B787-81205-SB710021-

00 was released to inspect the forward engine mount barrel nuts on some airplanes. The inspections were

performed on all of the airplanes in the effectivity, and no cracks were found. Nonetheless, the barrel nut

has been redesigned. The newly designed barrel nut has increased strength due to its improved features.

There is a deeper counterbore to help prevent high stress concentrations around the saddle of the barrel

nut. As well, the barrel nut has more material added to it than the previous barrel nut to increase strength.

In addition, the installation torque is reduced to prevent the newly designed barrel nuts from cracking.

Airplanes in Group 2 of this service bulletin effectivity were delivered with the newly designed barrel nut part

number on the forward engine mount. However, there is concern that the old barrel nut part number could

have been installed during maintenance activity. These airplanes must verify that the old barrel nut part

number was not installed after delivery during an engine change or other maintenance activity.

Boeing Service Related Problem (SRP) 787-SRP-54-0151 is related to this service bulletin.

This table is provided to operators for planning purposes only. Refer to the applicable sections for more information.

Applicable To: B787-A-71-00-0026-00A-931C-D

Model 787 Issue 001, 10 Jun 2015

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AIRCRAFT SERVICE BULLETIN
Table 1 

Planning Data Affected Data Module Reference

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 1.B., Spares AffectedSpares Affected Yes

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 5., ComplianceAD Related Yes

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 8., Weight and Balance ChangesWeight and Balance Changed No

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 9., Electrical Load DataElectrical Load Changed No

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 11., Publications AffectedPublications Affected Yes

Data Module SB B787-A-71-00-0026-00A-932AD, Paragraph 11., Publications AffectedAirplane Flight Operations Affected (Flight Crew No

Operations Manual and/or FAA Approved Airplane Flight Manual)

Data Module SB B787-A-71-00-0026-00A-934AD, Paragraph 3.A., Kits/PartsKits/Parts Required Yes

Data Module SB B787-A-71-00-0026-00A-934AD, Paragraph 3.B., Parts and Materials Supplied

by the Operator

Operator Supplied Parts/Material Yes

Data Module SB B787-A-71-00-0026-00A-934AD, Paragraph 6., Special Tooling Necessary to

do this Service Bulletin

Special Tooling Required No

3. ACTION

(CN-AA49111C)

Group 1:

On each engine, replace the four forward engine mount barrel nuts.

Group 2:

Review maintenance records and inspect, as necessary, to determine if barrel nut part number

SL4081C14SP1 is installed at any forward engine mount location. If needed, contact Boeing for necessary

action and do the required action.

Group 1-2:

4. EFFECTIVITY

787-8 and 787-9 Airplanes equipped with General Electric GEnx-1B engines. Refer to Data Module SB

B787-A-71-00-0026-00A-932A-D, Paragraph 1., Effectivity for the list of affected airplanes.

Applicable To: B787-A-71-00-0026-00A-931C-D

Model 787 Issue 001, 10 Jun 2015

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
5. 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.

Group 1:

Boeing recommends that the changes given in this service bulletin be done on both engines within 2 years

after the Issue 001 date on this service bulletin.

Group 2:

Boeing recommends that the inspection and any necessary changes that result from the inspection given

in this service bulletin be done on both engines within 2 years after the Issue 001 date on this service bulletin.

Group 1-2:

6. INDUSTRY SUPPORT INFORMATION

Boeing warranty remedies are available for airplanes in warranty as of June 5, 2014. Please refer to Data

Module SB B787-A-71-00-0026-00A-934A-D, Paragraph 2., Industry Support Information. The warranty

remedies will expire eight years from the Issue 001 date of this service bulletin.

7. MANPOWER

Refer to Data Module SB B787-A-71-00-0026-00A-932A-D, Paragraph 7., Manpower.

8. MATERIAL INFORMATION

Boeing Supplied Kits/Parts.

Refer to Data Module SB B787-A-71-00-0026-00A-934A-D, Paragraph 1., Material - Price and Availability.

Operators are encouraged to complete the survey provided in Data Module Appendix A, SB B787-A-71-00-

0026-0AA-931D-D of this service bulletin to help Boeing predict the quantity and timing of the Boeing Supplied

Kits/Parts.

Applicable To: B787-A-71-00-0026-00A-931C-D

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B787-81205-SB710026-00

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AIRCRAFT SERVICE BULLETIN
ICN-B787-A-000061-A-81205-10382-A-01-1

Figure 1 

Applicable To: B787-A-71-00-0026-00A-931C-D

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B787-81205-SB710026-00

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AIRCRAFT SERVICE BULLETIN
Service Bulletin B787-81205-SB710026-00

PLANNING INFORMATION

References

Reference Title

SB B787-A-71-00-0026-00A-933A-D Issue 001, Step 2. Work Instructions

SB B787-A-71-00-0026-00A-934A-D Issue 001, Parts Necessary for Each Airplane

Paragraph 3.

SOPM 20-50-01 BOLT AND NUT INSTALLATION

SWPM 20-10-11 Standard Wiring Practices Manual

SWPM 20-10-12 Standard Wiring Practices Manual

SWPM 20-10-19 Standard Wiring Practices Manual

787 AMM G71-00-00 POWER PLANT

787 AMM 27-51-00 TRAILING EDGE FLAP SYSTEM

787 AMM 27-81-00 LEADING EDGE SLAT SYSTEM

787 AMM 54-62-01 FORWARD FAIRINGS

787 AMM G71-11-04 FAN COWLS

787 AMM G78-31-00 THRUST REVERSER SYSTEM

Description

Group 1-2:

1. Effectivity

A. Airplanes

This service bulletin is applicable to 787-8 and 787-9 Airplanes equipped with General Electric GEnx1B engines, line numbers 6, 11, 20-138, 141-277, 281-285, and 288-301 in two Groups. The Variable

Numbers and Group information for the applicable airplanes is given below. Refer to CN-AA49111 for

data about this change.

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
Table 1 

GROUP CONFIGURATION DESCRIPTION

787 airplanes equipped with GEnx-1B engines that were delivered

with part number SL4081C14SP1 barrel nuts installed on the forward

engine mount.

1 -

787 airplanes equipped with GEnx-1B engines that were delivered

with part number SL4750NA barrel nuts installed on the forward engine

mount. These airplanes need to verify that part number

SL4081C14SP1 barrel nuts were not installed due to a maintenance

activity.

2 -

Airplane Models: 787-8, 787-9

Table 2 

Variable Number Group

ZA006 1

ZA152-ZA153 2

ZA175-ZA189 1

ZA195-ZA196 1

ZA197-ZA200 2

ZA215-ZA221 1

ZA222 2

ZA230-ZA247 1

ZA248-ZA249 2

ZA260-ZA269 1

ZA285-ZA295 1

ZA296 2

ZA317-ZA322 1

ZA323-ZA324 2

ZA327 1

ZA334 1

ZA335 2

ZA341-ZA342 2

ZA380-ZA389 1

ZA430-ZA437 1

ZA438-ZA439 2

Applicable To: B787-A-71-00-0026-00A-932A-D

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AIRCRAFT SERVICE BULLETIN
Table 2 

Variable Number Group

ZA460-ZA477 1

ZA478-ZA481 2

ZA560-ZA567 1

ZA586 1

ZA610-ZA614 1

ZA615-ZA617 2

ZA655-ZA660 1

ZA661 2

ZA680-ZA681 1

ZA682-ZA683 2

ZA695 1

ZA715-ZA716 1

ZA740 1

ZA741 2

ZA783-ZA784 2

ZA817-ZA822 2

ZA841 2

ZA846-ZA848 2

ZB077-ZB078 2

ZB167-ZB168 1

ZB169-ZB172 2

ZB299 2

B. Spares Affected

Examine your spares supply for the parts or components identified below. If any parts or components

are found, refer to Data Module SB B787-A-71-00-0026-00A-933A-D, Step 2., Work Instructions for

the recommended action.

Table 3 

Part Number

SL4081C14SP1

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B787-81205-SB710026-00

Issue 001, 10 Jun 2015

AIRCRAFT SERVICE BULLETIN
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 Data Module SB B787-A-71-00-0026-

00A-934A-D, Paragraph 3., Parts Necessary for Each Airplane, for the recommended use.

Table 4 

Part Number Dash Number

-5, -6, -30, -36, -38, -39,

-40, -44, -45, -46, -47,

-48, -49, -52, -53, -55,

-61

QECGE787

2. Concurrent Requirements

None.

3. Reason

Accomplishment of this service bulletin will replace the barrel nuts on the forward engine mount. The forward

engine mount barrel nuts have been redesigned to reduce the likelihood of cracking. A crack on both sides

of the barrel nut could cause complete failure of the barrel nut. Complete failure of two or more barrel nuts

on the same engine reduces the load capacity of the forward engine mount and could result in possible

separation of an engine from the airplane during flight. Separation of an engine under power could result

in loss of control of the airplane.

An operator reported that while replacing the No. 2 engine on a 747-8 airplane, the Non Destructive Test

(NDT) inspection of the barrel nuts on the forward engine mount revealed cracks on two of the four barrel

nuts. The operator also discovered one cracked barrel nut on the No. 1 engine of the 747-8 airplane. This

was the first reported occurrence on the 747-8. The Boeing Company did a Non Destructive Test (NDT)

inspection of barrel nuts on a flight test 747-8 airplane. There were two barrel nuts where a crack had initiated. A service bulletin was issued to initiate inspections of the forward engine mount barrel nuts for the

747-8 fleet. Operators have reported three additional cracked barrel nuts on three separate airplanes since

the release of that service bulletin. These barrel nuts are located at the forward end of the strut box and

are used to fasten the forward engine mount to the strut. A barrel nut with a crack on one side will still be

able to carry ultimate load. A crack on both sides of the barrel nut could cause complete failure of the barrel

nut. Boeing has not received any reports of a barrel nut with a crack on both sides.

787 airplanes with General Electric (GE) engines have a similar forward engine mount configuration and

use the same barrel nut part number as the 747-8. Therefore, Boeing service bulletin B787-81205-SB710021-

00 was released to inspect the forward engine mount barrel nuts on some airplanes. The inspections were

performed on all of the airplanes in the effectivity, and no cracks were found. Nonetheless, the barrel nut

has been redesigned. The newly designed barrel nut has increased strength due to its improved features.

There is a deeper counterbore to help prevent high stress concentrations around the saddle of the barrel

nut. As well, the barrel nut has more material added to it than the previous barrel nut to increase strength.

In addition, the installation torque is reduced to prevent the newly designed barrel nuts from cracking.

Airplanes in Group 2 of this service bulletin effectivity were delivered with the newly designed barrel nut

part number on the forward engine mount. However, there is concern that the old barrel nut part number

could have been installed during maintenance activity. These airplanes must verify that the old barrel nut

part number was not installed after delivery during an engine change or other maintenance activity.

Boeing Service Related Problem (SRP) 787-SRP-54-0151 is related to this service bulletin.

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4. Description

Group 1:

On each engine, replace the four forward engine mount barrel nuts.

Group 2:

Review maintenance records and inspect, as necessary, to determine if barrel nut part number

SL4081C14SP1 is installed at any forward engine mount location. If needed, contact Boeing for necessary

action and do the required action.

Group 1-2:

The work in this service bulletin is done in the maintenance zone(s) given below.

Table 5 

Affected Maintenance Zones

Model Zone

787-8, 787-9 411, 421

5. 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.

Group 1:

Boeing recommends that the changes given in this service bulletin be done on both engines within 2 years

after the Issue 001 date on this service bulletin.

Group 2:

Boeing recommends that the inspection and any necessary changes that result from the inspection given

in this service bulletin be done on both engines within 2 years after the Issue 001 date on this service bulletin.

Group 1-2:

6. 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.

7. Manpower

The table below shows an estimate of the task hours necessary to do this change 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:

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– Time to adjust to the workplace

– Time to schedule the work

– Time to inspect the work

– Time to cure the materials

– Time to make the parts

– Time to find the tools

Group 1:

Table 6 WORK PACKAGE 1: FORWARD ENGINE MOUNT BARREL NUT 

CHANGE, LEFT ENGINE

Number of Per- Task Hours Elapsed Hours

sons

Task

Open Access/Pre- 3 5.25 1.75

pare

Task 1 2 4.00 2.00

Close Access 3 5.25 1.75

TOTAL FOR LEFT ENGINE 14.50 5.50

Group 1:

Table 7 WORK PACKAGE 2: FORWARD ENGINE MOUNT BARREL NUT 

CHANGE, RIGHT ENGINE

Number of Per- Task Hours Elapsed Hours

sons

Task

Open Access/Pre- 3 5.25 1.75

pare

Task 1 2 4.00 2.00

Close Access 3 5.25 1.75

TOTAL FOR RIGHT ENGINE 14.50 5.50

Group 1:

NOTE: The task hour estimates above include the time necessary to install the forward bootstrap tool and

remove the load from the forward engine mount in order to replace the barrel nuts. As an alternative,

operators can replace the barrel nuts when an engine is changed. Refer to 787 AMM G71-00-00

as an accepted procedure to remove and install an engine. 

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Group 2:

Table 8 WORK PACKAGE 2: FORWARD ENGINE MOUNT BARREL NUT, 

INSPECTION FOR INSTALLED BARREL NUT PART NUMBER

Number of Per- Task Hours Elapsed Hours

sons

Task

1.00 *[1] 2.00 Open Access/Pre- 2 *[1]

pare for Inspection

0.60 *[1] 0.60 Inspect 1 *[1]

1.00 *[1] 2.00 Close Access 2 *[1]

2.60 *[1] 4.60 TOTAL FOR EACH ENGINE *[1]

*[1] These hours will only be necessary if the installed barrel nut part number cannot be verified by a

review of maintenance records.

Group 1-2:

8. Weight and Balance Changes

None.

9. Electrical Load Data

Not changed.

10. References

A. Existing Data:

1. Change Notice CN-AA49111C

2. Aircraft Maintenance Manual (AMM) 787 AMM 27-51-00, 787 AMM 27-81-00, 787 AMM 54-62-

01, 787 AMM G71-00-00, 787 AMM G71-11-04, 787 AMM G78-31-00

3. Standard Overhaul Practices Manual (SOPM) SOPM 20-50-01

4. Standard Wiring Practices Manual (SWPM) SWPM 20-10-11, SWPM 20-10-12, SWPM 20-10-19

5. Boeing Service Related Problem (SRP) 787-SRP-54-0151

6. Boeing Service Bulletin B787-81205-SB710021-00

B. Data Supplied with this Service Bulletin:

None.

C. Installation Requirement Modules Used in the Preparation of this Service Bulletin:

Table 9 

Requirement Mod- Title

ule

711Z4010 ENGINE TO PYLON INSTALLATION

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The Requirements Modules above were used to prepare this service bulletin. The Requirements

Modules are not necessary to make the specified changes, and are not supplied with this service bulletin.

The Requirements Modules may not be applicable to all airplane configurations or operators.

11. Publications Affected

Table 10 

Publication Chapter-Section

787 Maintenance Manual 71-00

787 Illustrated Parts Data ZA4-13, ZA4-23, 71-21

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 affects FCS but no new DTIs are necessary.

12. Interchangeability and Intermixability of Parts

Refer to Data Module SB B787-A-71-00-0026-00A-934A-D, Paragraph 3., Parts Necessary for Each Airplane,

for interchangeability and intermixability information.

13. Software Accomplishment Summary

Not Affected.

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Service Bulletin B787-81205-SB710026-00

MATERIAL INFORMATION

References

Reference Title

Service Bulletin

B787-81205-SB710026-00 – Appendix A – PART

DEMAND INTENT [Group 1: ]

SB B787-A-71-00-0026-0AA-931D-D Issue 001

SB B787-A-71-00-0026-00A-932A-D Issue 001, References

Paragraph 10.

Description

Group 1-2:

1. Material - Price and Availability

Group 1:

Boeing can supply the kit shown in Paragraph 3., Parts Necessary for Each Airplane. 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.

Group 1:

Reference this service bulletin and submit your purchase order by one of these methods:

Group 1:

1. Order on-line via ATA Spec 2000 or The Boeing PART Page

2. Fax to (206) 662-7145

Group 1:

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.

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Group 1:

Table 1 

Unit Price as of the

Issue 001 date of

this Service Bulletin (US Dollars)

ROLT as of the Issue 001 date of this

Service Bulletin

(Calendar Days)

Kit Number Name Date QTY

SERVICE BUL- December 16, 2014 20 186 $1,988.00

LETIN TOP KIT -

GENX-1B FORWARD ENGINE

MOUNT BARREL

NUT REPLACEMENT

036Z0257-1

January 16, 2015 10

February 20, 2015 10

March 16, 2015 10

April 15, 2015 10

May 15, 2015 10

June 15, 2015 10

July 15, 2015 10

August 17, 2015 10

Group 1:

Operators are encouraged to complete the survey provided in Data Module Appendix A, SB B787-A-71-00-

0026-0AA-931D-D of this service bulletin to help Boeing predict the quantity and timing of the Boeing Supplied

Kits/Parts.

Group 2:

None.

Group 1-2:

2. Industry Support Information

Boeing warranty remedies are available for 787 airplanes in warranty as of June 5, 2014. For task hour reimbursement for airplanes in warranty as of that date, send a warranty claim to Boeing Fleet Support Contracts

- Warranty. The kits for airplanes in warranty as of that date will be supplied at no charge. Send a purchase

order for the kits to Boeing Material Management. Please refer to this service bulletin number and reference

the airplane variable numbers in your purchase order. The warranty remedies will expire eight years from

the Issue 001 date of this service bulletin.

3. Parts Necessary for Each Airplane

A. Kits/Parts:

Group 1:

To get the kits/parts shown below, refer to Paragraph 1., Material - Price and Availability.

Group 1:

NOTE: One top kit and the items shown in Paragraph 3.B., Parts and Materials Supplied by the Operator, are necessary for each engine. 

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Group 1:

Table 2 

Kit 036Z0257

Existing Part Notes

Number

New Part Number QTY Name

-1

SERVICE BULLETIN TOP KIT -

GENX-1B FORWARD ENGINE

MOUNT BARREL

NUT REPLACEMENT

036Z0257-1 -

711Z4010-805 1 RETROFIT KIT

Group 1:

Table 3 

Kit 711Z4010

Existing Part Notes

Number

New Part Number QTY Name

-805

711Z4010-805 - RETROFIT KIT

*[1] *[2]

*[3]

BARREL NUT, SL4081C14SP1

SELF-LOCKING

SL4750NA 4

*[1] Discard the existing part.

*[2] This part is used in production.

*[3] You cannot use the existing part to replace the new or changed part.

Group 2:

None.

Group 1-2:

B. Parts and Materials Supplied by the Operator:

Group 1:

Table 4 

Part Number / QTY Name Notes

Specification

NEVER-SEEZ PURE NICKEL *[1]

SPECIAL ANTI-SEIZE

- -

*[1] USM Corp. Sub of Emhart Industries Inc Bostik Div (V70707), 211 Boston St, Middleton 01949, Essex, MA.

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Group 2:

None.

Group 1-2:

C. Parts Modified and Reidentified:

None.

D. Parts Removed and Not Replaced:

None.

4. Parts Necessary to Change Spares

None.

5. Special Tooling - Price and Availability

None.

6. Special Tooling Necessary to do this Service Bulletin

No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and

overhaul tools in the manuals given in Data Module SB B787-A-71-00-0026-00A-932A-D, Paragraph 10.,

References, can be necessary. Examine operator tool supply to make sure all necessary tools are available.

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Service Bulletin B787-81205-SB710026-00

ACCOMPLISHMENT INSTRUCTIONS

References

Reference Title

SB B787-A-71-00-0026-00A-932A-D Issue 001, References

Paragraph 10.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Manpower

Paragraph 7.

SB B787-A-71-00-0026-00A-932A-D Issue 001, Compliance

Paragraph 5.

Service Bulletin B787-81205-SB710026-00 – Task

1 – FORWARD ENGINE MOUNT BARREL NUT

REPLACEMENT [Group 1: ]

SB B787-A-71-00-0026-01A-933B-D Issue 001

SWPM 20-10-11 Standard Wiring Practices Manual

SWPM 20-10-12 Standard Wiring Practices Manual

SWPM 20-10-19 Standard Wiring Practices Manual

SOPM 20-50-01 BOLT AND NUT INSTALLATION

787 AMM G71-00-00 POWER PLANT

787 AMM 27-81-00 LEADING EDGE SLAT SYSTEM

787 AMM 27-51-00 TRAILING EDGE FLAP SYSTEM

787 AMM G78-31-00 THRUST REVERSER SYSTEM

787 AMM G71-11-04 FAN COWLS

787 AMM 54-62-01 FORWARD FAIRINGS

Procedure

Group 1-2:

1. GENERAL INFORMATION

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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 Data Module SB B787-A-71-00-0026-00A932A-D, Paragraph 10., 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 work packages. Task Hours and Elapsed Hours for each

package are given in Data Module SB B787-A-71-00-0026-00A-932A-D, Paragraph 7., Manpower.

You can do each work package 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 SRM Chapter 51

– Torque Values:

– Values for structural fasteners are given in 787 Structural Repair Manual, Chapter 51.

– Values for airframe maintenance tasks are included in Chapter 20 of 787 Aircraft Maintenance Manual (AMM).

– Values for electrical maintenance tasks are included in Chapter 20 of Standard Wiring

Practices Manual (SWPM).

– Values for engine maintenance tasks are included in Chapter 70 of 787 Aircraft Maintenance Manual (AMM).

– Non-standard torque values for maintenance tasks are included in the applicable installation step.

5. Use the approved fastener, process and material substitutions in accordance with SRM Chapter

51.

6. Refer to the SWPM 20-10-11 and SWPM 20-10-12 for the wire installation procedures, and

SWPM 20-10-19 for the wire separation requirements, as accepted procedures.

7. The necessary conditions for selection of clamp type and size are included in SWPM 20-10-12.

If any wire bundle support clamp specified in this service bulletin does not make a correct fit on

the wire bundle, refer to SWPM 20-10-12 as an accepted procedure to select a clamp that fits

correctly.

8. If the length of any fastener specified in this service bulletin does not meet the installation

standards in SRM Chapter 51, then a fastener of the same specification, or an approved substitute, with a length which meets the installation standards in SRM Chapter 51 may be used. In

addition, washers may be installed for fastener grip length in accordance with SRM Chapter 51.

Refer to SOPM 20-50-01 for alternate full threaded fasteners (screws) needed for installation

in this service bulletin.

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9. A Detailed Inspection is defined as: An intensive examination of a specific item, installation, or

assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented

with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such

as mirrors, magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures

may be required.

10. 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.

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.

13. This service bulletin includes functional test procedures for the systems changed by this service

bulletin. More functional tests can possibly be necessary in accordance with standard maintenance practices because of interruption to other airplane systems.

14. If shading is used, shaded areas in Tasks are to separate the non-critical and non-authoritative

information from the critical and authoritative information.

15. Use of colors in Tasks is based on guidance from the S1000D International specification for

technical publications.

16. The compliance times for the actions in Step 2., Work Instructions are in Data Module SB B787-

A-71-00-0026-00A-932A-D, Paragraph 5., Compliance.

17. Some steps in the Work Instructions are identified as Required for Compliance (RC). If this

service bulletin is mandated by an Airworthiness Directive (AD), then the steps identified as RC,

including steps indented under an RC step, must be done to comply with the AD. An Alternative

Method of Compliance (AMOC) is required for any deviations to RC steps, including indented

steps. For steps not identified as RC, alternative procedures can be used, and an AMOC is not

necessary, provided the RC steps, including indented steps, can still be done as specified, and

the airplane can be put back in a serviceable condition.

2. WORK INSTRUCTIONS

Group 1:

A. WORK PACKAGE 1: FORWARD ENGINE MOUNT BARREL NUT CHANGE, LEFT ENGINE

These work instructions provide the steps necessary to install the forward bootstrap tool and

remove the load from the forward engine mount in order to replace the barrel nuts. As an alterNOTE:

native, operators can replace the barrel nuts when an engine is changed. Refer to 787 AMM

G71-00-00 as an accepted procedure to remove and install an engine. 

(1) Make sure the leading edge slats and trailing edge flaps are retracted and deactivated. Refer to

787 AMM 27-81-00 and 787 AMM 27-51-00 as accepted procedures.

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(2) Make sure the thrust reversers are retracted and deactivated. Refer to 787 AMM G78-31-00 as an

accepted procedure.

(3) Do these steps to make sure that the ENGINE START switch and the FUEL CONTROL switch are

not operated:

(a) On the pilot's overhead panel, P5, make sure that the applicable ENGINE START switch is in

the NORM position.

(b) Put a DO-NOT-OPERATE tag on the applicable ENGINE START switch.

(c) On the control stand, P10, make sure that the applicable FUEL CONTROL switch is in the

CUTOFF position.

(d) Put a DO-NOT-OPERATE tag on the applicable FUEL CONTROL switch.

(4) Remove the fan cowl. Refer to 787 AMM G71-11-04 as an accepted procedure.

(5) Remove the forward fairing. Refer to 787 AMM 54-62-01 as an accepted procedure.

(6) Install the forward bootstrap tool assembly to the pylon. Refer to 787 AMM G71-00-00 as an accepted procedure.

(7) Install the two engine-to-bootstrap interface brackets to the engine fan case. Refer to 787 AMM

G71-00-00 as an accepted procedure.

(8) Attach the forward bootstrap tool hoists to the engine. Refer to 787 AMM G71-00-00 as an accepted

procedure.

(9) Apply a compressive force to the forward engine mount. Refer to 787 AMM G71-00-00 as an accepted procedure.

NOTE: You apply the compressive force to the engine mount to remove the tension load from the

forward engine mount bolts. 

(10) RC - Replace the forward engine mount barrel nuts in accordance with Data Module Task 1, SB

B787-A-71-00-0026-01A-933B-D.

(11) Remove the compressive force from the forward engine mount. Refer to 787 AMM G71-00-00 as

an accepted procedure.

(12) Remove the forward bootstrap tool hoists from the engine and remove the two engine-to-bootstrap

interface brackets from the engine fan case. Refer to 787 AMM G71-00-00 as an accepted procedure.

(13) Remove the forward bootstrap tool assembly. Refer to AMM 787 AMM G71-00-00 as an accepted

procedure.

(14) Install the forward fairing. Refer to 787 AMM 54-62-01 as an accepted procedure.

(15) Install the fan cowl. Refer to 787 AMM G71-11-04 as an accepted procedure.

(16) Do these steps to remove the DO-NOT-OPERATE tags from the applicable ENGINE START switch

and FUEL CONTROL switch.

(a) On the pilot's overhead panel, P5, remove the DO-NOT-OPERATE tag from the applicable

ENGINE START switch.

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(b) On the control stand, P10, remove the DO-NOT-OPERATE tag from the applicable FUEL

CONTROL switch.

(17) Activate the thrust reversers. Refer to 787 AMM G78-31-00 as an accepted procedure.

(18) Activate the leading edge slats and trailing edge flaps. Refer to 787 AMM 27-81-00 and 787 AMM

27-51-00 as accepted procedures.

(19) Put the airplane back to a serviceable condition.

Group 1:

B. WORK PACKAGE 2: FORWARD ENGINE MOUNT BARREL NUT CHANGE, RIGHT ENGINE

These work instructions provide the steps necessary to install the forward bootstrap tool and

remove the load from the forward engine mount in order to replace the barrel nuts. As an alterNOTE:

native, operators can replace the barrel nuts when an engine is changed. Refer to 787 AMM

G71-00-00 as an accepted procedure to remove and install an engine. 

(1) Make sure the leading edge slats and trailing edge flaps are retracted and deactivated. Refer to

787 AMM 27-81-00 and 787 AMM 27-51-00 as accepted procedures.

(2) Make sure the thrust reversers are retracted and deactivated. Refer to 787 AMM G78-31-00 as an

accepted procedure.

(3) Do these steps to make sure that the ENGINE START switch and the FUEL CONTROL switch are

not operated:

(a) On the pilot's overhead panel, P5, make sure that the applicable ENGINE START switch is in

the NORM position.

(b) Put a DO-NOT-OPERATE tag on the applicable ENGINE START switch.

(c) On the control stand, P10, make sure that the applicable FUEL CONTROL switch is in the

CUTOFF position.

(d) Put a DO-NOT-OPERATE tag on the applicable FUEL CONTROL switch.

(4) Remove the fan cowl. Refer to 787 AMM G71-11-04 as an accepted procedure.

(5) Remove the forward fairing. Refer to 787 AMM 54-62-01 as an accepted procedure.

(6) Install the forward bootstrap tool assembly to the pylon. Refer to 787 AMM G71-00-00 as an accepted procedure.

(7) Install the two engine-to-bootstrap interface brackets to the engine fan case. Refer to 787 AMM

G71-00-00 as an accepted procedure.

(8) Attach the forward bootstrap tool hoists to the engine. Refer to 787 AMM G71-00-00 as an accepted

procedure.

(9) Apply a compressive force to the forward engine mount. Refer to 787 AMM G71-00-00 as an accepted procedure.

NOTE: You apply the compressive force to the engine mount to remove the tension load from the

forward engine mount bolts. 

(10) RC - Replace the forward engine mount barrel nuts in accordance with Data Module Task 1, SB

B787-A-71-00-0026-01A-933B-D.

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(11) Remove the compressive force from the forward engine mount. Refer to 787 AMM G71-00-00 as

an accepted procedure.

(12) Remove the forward bootstrap tool hoists from the engine and remove the two engine-to-bootstrap

interface brackets from the engine fan case. Refer to 787 AMM G71-00-00 as an accepted procedure.

(13) Remove the forward bootstrap tool assembly. Refer to AMM 787 AMM G71-00-00 as an accepted

procedure.

(14) Install the forward fairing. Refer to 787 AMM 54-62-01 as an accepted procedure.

(15) Install the fan cowl. Refer to 787 AMM G71-11-04 as an accepted procedure.

(16) Do these steps to remove the DO-NOT-OPERATE tags from the applicable ENGINE START switch

and FUEL CONTROL switch.

(a) On the pilot's overhead panel, P5, remove the DO-NOT-OPERATE tag from the applicable

ENGINE START switch.

(b) On the control stand, P10, remove the DO-NOT-OPERATE tag from the applicable FUEL

CONTROL switch.

(17) Activate the thrust reversers. Refer to 787 AMM G78-31-00 as an accepted procedure.

(18) Activate the leading edge slats and trailing edge flaps. Refer to 787 AMM 27-81-00 and 787 AMM

27-51-00 as accepted procedures.

(19) Put the airplane back to a serviceable condition.

Group 2:

C. WORK PACKAGE 3: FORWARD ENGINE MOUNT BARREL NUT, INSPECTION FOR INSTALLED

BARREL NUT PART NUMBER

(1) RC - For each airplane engine, review maintenance records to determine if the airplane engine has

been removed/installed or replaced.

(a) If the airplane engine has not been removed/installed or replaced, no further action is required

for this engine for Work Package 3.

(b) If the airplane engine has been removed/installed or replaced, review maintenance records to

determine if barrel nut part number SL4081C14SP1 was installed at any forward engine mount

location. After reviewing maintenance records to determine if barrel nut part number

SL4081C14SP1 was installed, do one of the following:

1) If maintenance records conclusively show that barrel nut part number SL4081C14SP1 was

not installed, no further action is required for this engine for Work Package 3.

2) If maintenance records indicate that barrel nut part number SL4081C14SP1 was installed,

or if the installation status of barrel nut part number SL4081C14SP1 is not conclusive, do

the following steps on the applicable engine:

a) Get access to the forward engine mount for inspection. Remove the forward fairing.

Refer to 787 AMM 54-62-01 as an accepted procedure.

NOTE: Access may be gained by opening the fan cowl if the appropriate lift or ladder

equipment is available. To open the fan cowl, refer to 787 AMM G71-11-04 as

Applicable To: B787-A-71-00-0026-00A-933A-D

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an accepted procedure. Otherwise, access to the forward engine mount has

been confirmed from above by removing the forward fairing. 

b) Do a detailed inspection of the four forward engine mount barrel nut locations to determine

if the installed barrel nut is part number SL4750NA or part number SL4081C14SP1.

Barrel nut part number SL4750NA has two vertical grooves cut into each face of the

barrel nut. Barrel nut part number SL4081C14SP1 has a smooth face, which may include

part or serial number information. After doing the detailed inspection, do one of the following:

<1> If barrel nut part number SL4750NA is installed at all four locations, install the forward fairing and close the fan cowl, if opened, as described below.

<2> If barrel nut part number SL4081C14SP1 is installed at any location, or if the barrel

nut part number cannot be determined, contact Boeing for the necessary action

and do the required action.

c) Install the forward fairing. Refer to 787 AMM 54-62-01 as an accepted procedure.

d) Close the fan cowl, if opened. Refer to 787 AMM G71-11-04 as an accepted procedure.

e) Put the airplane back to a serviceable condition.

Applicable To: B787-A-71-00-0026-00A-933A-D

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Service Bulletin B787-81205-SB710026-00

Task 1 – FORWARD ENGINE MOUNT BARREL NUT REPLACEMENT [Group

1: ]

References

Reference Title

SOPM 20-50-07 LUBRICATION

787 AMM G71-00-00 POWER PLANT

Preliminary Requirements

Required Conditions

Action/Condition Data Module/Technical Publication

Service Bulletin B787-81205-SB710026-00 - B787-A-71-00-0026-00A-933A-D Issue 001

ACCOMPLISHMENT INSTRUCTIONS

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Procedure

This Task applies to Group 1:

ICN-B787-A-000061-A-81205-10383-A-01-1

Figure 1 

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ICN-B787-A-000061-A-81205-10384-A-01-1

Figure 2 

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ICN-B787-A-000061-A-81205-10385-A-01-1

Figure 3 

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1. The step numbers shown below agree with the numbers shown in the circle symbols in the Task. The QTY

numbers shown below are the number of parts necessary for each engine.

Table 1 

Step Action Name Identification Qty More Data

Refer to 787 AMM

G71-00-00 as an

accepted procedure.

1 Remove / Keep BOLT BACB30US14K39M 4

Refer to 787 AMM

G71-00-00 as an

accepted procedure.

Remove / Keep WASHER BACW10BP14ACU 4

Refer to 787 AMM

G71-00-00 as an

accepted procedure.

Remove NUT, BARREL SL4081C14SP1 4

Refer to 787 AMM

G71-00-00 as an

accepted procedure.

Remove / Keep RETAINER SLR4124C14 4

Remove any existing grease from the

bolt.

2 Clean BOLT - 4

Remove any existing grease from the

bolt hole.

Clean BOLT HOLE - 4

Remove any existing grease from the

barrel nut bores in

the forward engine

mount.

Clean BARREL NUT BORE - 4

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Table 1 

Step Action Name Identification Qty More Data

Do a Detailed Inspection of the kept

bolts for damage.

Replace any bolts

that have visible

damage found during inspection.

3 Inspect BOLT BACB30US14K39M 4

Do a Detailed Inspection of the kept

washers for damage. Replace any

washers that have

visible damage

found during inspection.

Inspect WASHER BACW10BP14ACU 4

Do a Detailed Inspection of the kept

retainers for damage. Replace any

retainers that have

visible damage

found during inspection.

Inspect RETAINER SLR4124C14 4

Apply anti-seize

compound to the

threads and shank

of the bolt and the

cylindrical surfaces

of the barrel nut.

Refer to SOPM 20-

50-07 as an accepted procedure.

NEVER-SEEZ PURE - 4

NICKEL SPECIAL ANTI-SEIZE

4 Apply

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Table 1 

Step Action Name Identification Qty More Data

CAUTION: DO NOT APPLY MORE THAN THE MAXIMUM SPECIFIED TORQUE WHEN YOU TIGHTEN

THE FASTENERS. DAMAGE TO THE PARTS MAY OCCUR IF TOO MUCH TORQUE IS

APPLIED.

Hold the retainers

on the barrel nuts

and put the retainers and barrel nuts

into the forward engine mount with the

rounded side of the

nuts facing up.

Make sure that the

barrel nuts align

correctly with the

bolt holes.

5 Install (New) BARREL NUT SL4750NA 4

Make sure that the

retainers are correctly installed in the index hole.

Install (Kept) RETAINER SLR4124C14 4

6 Install (Kept) BOLT BACB30US14K39M 4

Install countersunk

side of the washer

adjacent to the bolt

head.

Install (Kept) WASHER BACW10BP14ACU 4

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Table 1 

Step Action Name Identification Qty More Data

Monitor the torque

necessary to turn

the bolts. Make sure

that the barrel nut

run-on torque is

more than 70 inchpounds and less

than 600 inchpounds with the bolt

lubricated with Never-Seez Pure Nickel

Special anti-seize. If

the run-on torque is

not in the limits, replace the barrel nut.

If a barrel nut is replaced, check the

run-on torque of replacement barrel

nut.

BARREL NUT, SELF- SL4750NA 4

LOCKING

7 Torque

Tighten the bolts to

an initial torque of

1600-1800 inchpounds. Make sure

to tighten the bolts

evenly. Keep the

differences in torque

between the bolts to

a minimum.

8 Torque BOLT BACB30US14K39M 4

Tighten the bolts to

a final torque of

3300-3500 inchpounds. Make sure

to tighten the bolts

evenly. Keep the

differences in torque

between the bolts to

a minimum.

9 Torque BOLT BACB30US14K39M 4

After installing and

applying the full

torque to each of

the four bolts, re-apply the final torque

of 3300-3500 inchpounds to each bolt.

10 Torque BOLT BACB30US14K39M 4

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Service Bulletin B787-81205-SB710026-00

Appendix A – PART DEMAND INTENT [Group 1: ]

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Procedure

Group 1:

1.

ICN-B787-A-000061-A-81205-07008-A-01-1

Figure 1 

Applicable To: B787-A-71-00-0026-0AA-931D-D

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