1.PLANNING INFORMATION
A.Effectivity
* * * FOR GEnx-1B54, -1B58, -1B64, -1B67, -1B70
This Service Bulletin has been introduced in production to these GEnx-1B engines:
•
GEnx-1B engines, serial numbers 956-118 and up.
These serial numbers are the best available data.
The old left side link (link) P/N 2312M74G01 and left side link axe (axe) P/N 2313M21G02 are affected by this Service Bulletin.
B.Description
This Service Bulletin releases the new link P/N 2312M74G02 and axe P/N 2313M21G05.
C.Compliance
Category 7
GE recommends that you do this Service Bulletin at customer's convenience.
NOTE:
This Service Bulletin can be accomplished in shop.
D.Concurrent Requirements
None.
E.Reason
(1)Objective:
To improve reliability.
(2)Condition:
Deep wear marks were found on the left-hand (LH) vertical lugs of the accessory gearbox (AGB) housing during inspection of test engines.
(3)Cause:
An undesired degree of freedom of the vertical/horizontal mounting system permitted the link to make contact with the AGB housing lugs causing deep wear marks.
(4)Improvement:
The new link replaces one of the spherical bearings in the current link with a bushing. This removes the axial degree of freedom of the link system to prevent contact with the AGB without inducing an over constraint on the mount transverse link. The bolt at this location is also changed to be compatible with the bushing.
(5)Substantiation:
Substantiation is by comparative analysis and test.
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
No additional man-hours are required to comply with this Service Bulletin.
H.Weight and Balance
Weight and balance are not changed.
I.References (Use the latest version of these documents)
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)
NOTE:
The reference documents listed below are for the engine manufacturer's internal use only:
 
CID: 573204, 547398
 
BPP: 08-72-64-03
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
The new parts and serviceable old parts must be incorporated as a set.
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
 
2312M74G02
(1)
Link, LH Side
Quote
(-)
Quote
 
2313M21G05
(1)
Axe, Link LH
Quote
(-)
Quote
NOTE:
Prices are provided for planning purposes and are subject to change.
(2)Other Spare Parts:
None.
(3)Consumables:
None.
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
 
2376M20G05
(X)
Propulsor Module Assembly
2376M20G05
(X)
RM
-/-
 
.2312M74G02
25-160A, 72-00-02
(1)
Link, LH Side
(SIN 03801)
.2312M74G01
25-160, 72-00-02
(1)
RE
5/A
 
.2313M21G02
25-050A, 72-00-02
(1)
Axe, Link LH
(SIN 03828)
.2313M21G02
25-050, 72-00-02
(2)
QTC
5/A
 
.2313M21G05
25-055, 72-00-02
(1)
Axe, Link LH
(SIN 0382D)
--
(-)
AD
5/-
Operation Codes
AD=Add
QTC=Quantity Change RE=Replace
RM=Remains
Change Code 5=Qualified interchangeability. Refer to paragraph 1.K., Interchangeability.
Support Code A=Old parts will no longer be supplied.
D.Parts Disposition
Use serviceable old parts for engines that have not changed.
E.Tooling - Price and Availability
None.
3.ACCOMPLISHMENT INSTRUCTIONS
A.Removal
(1)Removal and installation instructions for the link (1, Figure 1) and axes (2, 3) have not changed. Refer to GEnx-1B EM, 72-00-02, DISASSEMBLY 003 and ASSEMBLY 004.
Introduction of New Link
Figure 1   (Sheet 1)
Introduction of New Link
Figure 1   (Sheet 2)