GE PROPRIETARY INFORMATION
The information contained in this document is GE proprietary information and is disclosed in confidence. It is the property of GE and shall not be used, disclosed to others or reproduced without the express written consent of GE, including, but without limitation, it is not to be used in the creation, manufacture, development, or derivation of any repairs, modifications, spare parts, designs, or configuration changes or to obtain FAA or any other government or regulatory approval to do so. If consent is given for reproduction in whole or in part, this notice and the notice set forth on each page of this document shall appear in any such reproduction in whole or in part.
This technical data is considered EAR controlled pursuant to 15 CFR Parts 730-774 respectively. Transfer of this data by any means to a Non-US Person, whether in the United States or abroad, without the proper U.S. Government authorization (e.g., License, exemption, NLR, etc.), is strictly prohibited.
Copyright (2014) General Electric Company, U.S.A.
1.PLANNING INFORMATION
A.Effectivity
* * * FOR GEnx-1B54, -1B54/P1, -1B54/P2, -1B58, -1B58/P1, -1B58/P2, -1B64, -1B64/P1, -1B64/P2, -1B67, -1B67/P1, -1B67/P2, -1B70, -1B70/72/P1, -1B70/72/P2, -1B70/75/P1, -1B70/75/P2, -1B70/P1, -1B70/P2, -1B74/75/P1, -1B74/75/P2, -1B75/P1, -1B75/P2, -1B78/P2
This Service Bulletin is applicable to all GEnx-1B engines.
This Service Bulletin has been introduced in production to these GEnx-1B engines:
•
GEnx-1B engines, serial numbers 956-330 and up.
These serial numbers are the best available data.
The machine bolt P/N AS3237-14 and flat washer P/N AN960C416L are affected by this Service Bulletin.
B.Description
This Service Bulletin releases the metal bumper P/N 2550M14P01 and replaces the current double hex head bolts with countersink bolts.
C.Compliance
Category 7
GE recommends that you do this Service Bulletin at customer's option.
NOTE:
This Service Bulletin can be accomplished on wing and/or in shop.
D.Concurrent Requirements
None.
E.Reason
(1)Objective:
To improve reliability.
(2)Condition:
The interference between the thrust reverser latch hook and engine hardware produces dents on the latch hook.
(3)Cause:
The purpose of this change is to protect the thrust reverser latch hook as well as the extension bracket from damage due to latch hook interference with engine hardware.
(4)Improvement:
The presence of a metal bumper as well as countersink bolts will mitigate the interface issue between the thrust reverser v-blade latch hook and the engine hardware.
(5)Substantiation:
Substantiation is by analysis and comparative analysis.

F.Approval
This Service Bulletin has been reviewed by the FAA and the repair(s) and modification(s) herein comply with the applicable Federal Aviation Regulations and are FAA APPROVED for installation in the model(s) listed in this Service Bulletin.
G.Manpower
After you get access to the fan module, you will need approximately 4 man-hours to do the replacement portion of this Service Bulletin.
H.Weight and Balance
The complete compliance with this Service Bulletin increases weight by 0.045 lb (0.02 kg).
I.References (Use the latest version of this document)
GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC)
NOTE:
The reference documents listed below are for the engine manufacturer's internal use only:
 
CID: 573950
 
BPP: 12-72-21-04
J.Publications Affected
GEK 112851, GEnx-1B Engine Manual (EM)
GEK 112862, GEnx-1B Cleaning, Inspection, and Repair Manual (CIR)
GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC)
K.Interchangeability
Qualified interchangeability.
L.Software Accomplishment Summary
Not applicable.
2.MATERIAL INFORMATION
A.Material - Price and Availability
(1)Parts necessary to do this Service Bulletin:
 
Part Number
Qty/ Eng
Part Name
Unit ($) Price
Pkg Qty
Lead Time Days
 
2550M14P01
(1)
Bumper, Metal
448.00
(1)
Quote
 
J952P15A
(2)
Bolt, Machine
33.50
(10)
5
NOTE:
Prices are provided for planning purposes and are subject to change.
(2)Other Spare Parts:
None.
(3)Consumables:
 
Code Number
Description
 
C01-159
Primer, Silicone (RTV primer)
 
C01-176
RTV, Silicone Elastomer (RTV)
 
C02-058
Compound, Thread Lubricating (lubricant)
 
C02-071
Anti-Seize and Lubricating Compound (anti-seize)
 
C03-001
Primer, Zinc Chromate (primer)
 
C03-100
Primer, Paint, Zinc-Molybdate, Alkyd Type (primer)
 
C04-035
Solvent, General (isopropyl alcohol)
B.Industry Support Information
None.
C.Configuration Chart
 
New Part Number
Qty/ Eng
Part Name
Old Part Number/ IPC Location
Qty/ Eng
Op Code
Chg/ Sprt Code
 
2305M18G07/G08
(X)
Assembly, Aft Fan Stator Case
2305M18G07/G08
(X)
RM
-/-
 
2447M18G01
(X)
Assembly, Aft Fan Stator Case
2447M18G01
(X)
RM
-/-
 
.2550M14P01
01-425, 72-21-00
(1)
Bumper, Metal
(SIN 84518)
--
(-)
AD
5/E
 
.J952P15A
01-451, 72-21-00
(2)
Bolt, Machine
(SIN 84522)
.AS3237-14
01-450, 72-21-00
(2)
RE
5/E
 
--
(-)
Bolt, Machine
(SIN 84522)
.AS3580-4-16
01-450A, 72-21-00
(ALT)
DE
5/E
 
.AN960C416L
01-471, 72-21-00
(2)
Washer, Flat
(SIN 84533)
.AN960C416L
01-470, 72-21-00
(4)
QTC
5/E
Operation Codes
AD=Add
QTC=Quantity Change RE=Replace
RM=Remains
Change Codes
5=Qualified interchangeability. Refer to paragraph 1.K., Interchangeability.
Support Codes
E=Old parts will be supplied, and can be used at other engine locations.
D.Parts Disposition
Use serviceable old parts at other engine locations.
Use serviceable old parts for engines that have not changed.
E.Tooling - Price and Availability
None.
3.ACCOMPLISHMENT INSTRUCTIONS
A.Removal
(1)Remove the lower left fillet fairing (1, Figure 1) and lower right fillet fairing (2). Refer to Figure 1 and do as follows:
NOTE:
If the fan module is split from the propulsor, this paragraph can be omitted. Go to paragraph 3.A.(2).
(a)Remove two machine screws (3) that attach the lower left fillet fairing to the deflector panel (4).
(b)Remove the five Torx bolts (5) and the two Torx bolts (6) that attach the lower left fillet fairing to the left side of the lower firewall (7).
(c)Remove two machine screws (3) that attach the lower left fillet fairing to the deflector panel (4).
(d)Remove the lower left fillet fairing (1).
(e)Remove the five Torx bolts (5) and the two Torx bolts (6) that attach the lower right fillet fairing to the right side of the lower firewall assembly.
(f)Remove the lower right fillet fairing (2).
(2)Remove the outlet guide vane (OGV) lower right extension panel (1, Figure 2) and OGV lower left extension panel (2) from the aft fan case (3) at the lower OGV fan pylon (4). Refer to Figure 2 and do as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
CAUTION:
MAKE SURE NOT TO TOUCH THE PANELS, PYLON, OR OGVS WHEN THE RTV IS CUT BETWEEN THE LOWER LEFT/RIGHT PANELS, OGV 25 PYLON, AND OGVS. SCRATCHES, SCORES, OR DAMAGE TO THE PANELS, PYLON, AND OGVS SURFACES CAN OCCUR.
(a)Cut the C01-176 RTV from the joints between the OGVs.
(b)Remove the Torx recess bolts (5) from the OGV extension panels.
(c)Remove the OGV extension panels from the OGV 25 pylon.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(d)After the OGV extension panels are removed, the remaining C01-0176 RTV from the panels, OGVs, and pylon can be cut or removed with C04-035 isopropyl alcohol or equivalent.
(3)Remove the surface cooler fairing (1, Figure 3) from the aft fan case and lower OGV fan pylon (2). Refer to Figure 3 and do as follows:
(a)Remove the screws (3) that attach the fairing to the aft fan case at the 6:00 o'clock position.
(b)Remove the fairing from the aft fan case and OGV 25 pylon.
B.Installation
(1)Install the metal bumper (4, Figure 4). Refer to Figure 4 and do as follows:
(a)Remove two self-locking nuts (1) and flat washers (2) from the ID side of the aft fan case.
(b)Remove two machine bolts (3) and flat washers (2) from the OD side of the aft fan case.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(c)Apply C02-071 anti-seize to the bolts.
(d)Attach the metal bumper (4) with two new machine bolts (5) on the OD side.
(e)Install two flat washers (2) and self-locking nuts (1) on the ID side.
(f)Torque the self-locking nuts (1) to 90.0 lb-in. (10.16 N.m).
(g)Loosen the self-locking nuts (1).
(h)Torque the self-locking nuts (1) again to 90.0 lb-in. (10.16 N.m).
(2)Install the surface cooler fairing (1, Figure 3) again as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(a)Apply C03-001 primer or C03-100 primer to the shank and bearing surfaces of two screws (3).
(b)Apply C02-058 lubricant to the threads of the screws (3).
(c)Install the fairing to the aft fan case at the 6:00 o'clock position with the screws (3).
(d)Torque the screws (3) to 83-97 lb in. (9.4-11.0 N.m).
(3)Install the OGV lower right extension panel (1, Figure 2) and OGV lower left extension panel (2) on the aft fan case (3) at the lower OGV fan pylon (4). Refer to Figure 2 and do as follows:
(a)Make sure all accessible components are installed before installation of the panels.
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(b)Apply C02-058 lubricant to the threads of the Torx recess bolts (5).
(c)Install the lower right extension panel (1) and the lower left extension panel (2) as follows:
1Align the lower right extension panel (1) and the lower left extension panel (2) holes with the lower OGV fan pylon (4).
2Attach the lower right extension panel (1) and the lower left extension panel (2) with the Torx recess bolts (5) at ten locations.
3Torque the Torx recess bolts (5) to 83-97 lb in. (9.4-11.0 N.m).
4Torque the Torx recess bolts (5) again to 83-97 lb in. (9.4-11.0 N.m).
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(d)Apply C01-159 RTV primer where the lower right extension panel (1) and the lower left extension panel (2) meet the lower seal (SIN 84509) and the lower left cowl seal (01-410, 72-21-00) or (01-411) and lower right cowl seal (01-400) or (01-401).
(e)Apply C01-176 RTV where the lower right extension panel (1) and the lower left extension panel (2) touch the lower left cowl seal (01-410) or (01-411) and lower right cowl seal (01-400) or (01-401).
(4)Install the lower left fillet fairing (1, Figure 1) and lower right fillet fairing (2). Refer to Figure 1 and do as follows:
WARNING:
REFER TO THE PRODUCT LABEL AND THE MANUFACTURERS (MATERIAL) SAFETY DATA SHEET (SDS) FOR INSTRUCTIONS ON THE HAZARDS, STORAGE, SAFE HANDLING AND PROPER USE OF THIS PRODUCT.
(a)Lubricate with C02-058 graphite the threads of ten Torx bolts (5), four Torx bolts (6), and four machine screws (3).
(b)Install the lower left fillet fairing (1) to the left side of the lower bridge with five Torx bolts (5), two Torx bolts (6), and two machine screws (3).
(c)Install the lower right fillet fairing (2) to the right side of the lower bridge with five Torx bolts (5), two Torx bolts (6), and two machine screws (3).
(d)Torque the 10 Torx bolts (5), four Torx bolts (6), and four machine screws (3) to 60-70 lb in. (6.8-7.9 N.m).
Removal/Installation of the Lower Fillet Fairings
Figure 1  
Removal/Installation of the OGV Lower Extension Panels
Figure 2  
Removal/Installation of the Surface Cooler Fairing
Figure 3  
Installation of the New Metal Bumper
Figure 4   (Sheet 1)
Installation of the New Metal Bumper
Figure 4   (Sheet 2)