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 keyed ring (No. 3 bearing keyed ring) P/N 2312M67P01 is affected by this Service Bulletin.
B.Description
This Service Bulletin introduces the improved No. 3 bearing keyed ring P/N 2312M67P02 that will reduce wear of the part and the scrap rate of this part at exposure.
C.Compliance
Category 5
GE recommends that you do this Service Bulletin as soon as the No. 3 bearing keyed ring is removed from the engine.
NOTE:
This Service Bulletin can be accomplished in shop.
This Service Bulletin is offered to improve the reliability or performance of your GE product, or to help prevent the occurrence of the event or condition described in this Service Bulletin. If the operator elects not to participate in the bulletin, that decision will be taken into consideration by GE in evaluating future product performance issues that may arise in the operators fleet.
D.Concurrent Requirements
None.
E.Reason
(1)Objective:
To introduce a new part, improve maintainability, and reduce cost of ownership.
(2)Condition:
The No. 3 bearing keyed ring on GEnx development engine does not show any appreciable wear after limited hours. Comparable hardware on GE90-115B engines does exhibit a wear phenomena, which leads to a high scrap rate of the No. 3 bearing keyed ring when exposed during an engine shop visit.
(3)Cause:
The analysis on contributing factors for excessive wear shows that the No. 3 bearing keyed ring has a limited radial engagement between keyed ring internal tabs and high pressure compressor (HPC) shaft slots.
(4)Improvement:
The new No. 3 bearing keyed ring increases the tabs length to improve the radial engagement capability to HPC shaft slots. Additionally, the number of outer tabs is increased from two to five to enhance the control of the position of the installed part.
(5)Substantiation:
Substantiation is by 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
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: 547604
 
BPP: 08-72-00-11
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
One-way interchangeable.
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
 
2312M67P02
(1)
Ring, Keyed
138.75
(1)
30
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
 
2376M20G01/G02/ G03/G04/G05
(X)
Propulsor Module Assembly
2376M20G01/G02/ G03/G04/G05
(X)
RM
-/-
 
.2312M67P02
20-471, 72-00-02
(1)
Ring, Keyed
(SIN 030AL)
.2312M67P01
20-470, 72-00-02
(1)
RE
1/A
Operation Codes
RE=Replace
RM=Remains
Change Code 1=One-way interchangeable.
Support Code A=Old parts will no longer be supplied.
D.Parts Disposition
Discard old parts.
E.Tooling - Price and Availability
None.
3.ACCOMPLISHMENT INSTRUCTIONS
A.General
(1)Removal and installation instructions for the No. 3 bearing keyed ring (1, Figure 1) have not changed. Refer to the GEnx-1B EM, 72-00-02, DISASSEMBLY 004 and ASSEMBLY 002.
Introduction of New No. 3 Bearing Keyed Ring
Figure 1   (Sheet 1)
Introduction of New No. 3 Bearing Keyed Ring
Figure 1   (Sheet 2)