TRANSMITTAL INFORMATION
REVISION 1 TO SERVICE BULLETIN 72-0106
Revision 1 is issued to update paragraphs 1.A., Effectivity and 2., MATERIAL INFORMATION.
The original was issued on the August 29, 2012. Revision bars in the left margin identify changes.
1.PLANNING INFORMATION
A.Effectivity
 
* * * FOR GEnx-1B64, -1B67, -1B70, -1B64/P1, -1B67/P1, -1B70/P1, -1B70/75/P1
This Service Bulletin has been introduced in production to these GEnx-1B engines:
 •
GEnx-1B engines, serial numbers 956-201, 956-202, 956-206, and up.
These serial numbers are the best available data.
The seal P/N 2301M68P01 is affected by this Service Bulletin.
B.Description
This Service Bulletin releases a new seal P/N 2503M02P01.
C.Compliance
Category 4
GE recommends that you do this Service Bulletin when the seal is exposed.
NOTE:
This Service Bulletin can be accomplished in shop.
NOTE:
Compliance with this Service Bulletin is terminating action for the current 4R seal control programme. After this Service Bulletin incorporates the new seal, the engine oil filter replacement will revert to "on condition". Also, S/B 79-0012 for filter replacement every 1,000 flight hours as well as filter replacement at reduced oil filter delta pressure limit of 10 psid (68 kPa) will no longer apply.
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 and improve reliability.
(2)Condition:
Heavy rubs can occur on the aft No. 4 bearing seal with the potential for the rubs to increase the clearances and the oil consumption rate to be affected.
(3)Cause:
The current seal is susceptible to a transient thermal instability, and depending upon the assembly tolerance stack-up, a heavy rub could occur on the aft No. 4 bearing seal.
(4)Improvement:
The new seal has improved cooling and is thermally stable, which results in more consistent stator clearance control and improved reliability.
(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
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)
GEnx-1B SB 79-0012, OIL SYSTEM - Lubrication Unit (79-21-10) - Replacement Interval for Oil Filter Element
NOTE:
The reference documents listed below are for the engine manufacturer's internal use only:
 
CID: 573563
 
BPP: 11-79-00-12
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
 
2503M02P01
(1)
Seal
3,111.00
(1)
5
NOTE:
Prices are provided for planning purposes and are subject to change.
(2)Other Spare Parts:
None.
(3)Consumables:
None.
B.Industry Support Information
Contact your Customer Support Manager (CSM) for support details.
C.Configuration Chart
 
New Part Number
Qty/ Eng
Part Name
Old Part Number/ IPC Location
Qty/ Eng
Op Code
Chg/ Sprt Code
 
2376M20G05-G06
(X)
Assembly, Propulsor Module
2376M20G05-G06
(X)
RM
-/-
 
.2503M02P01
35-400A, 72-00-02
(1)
Seal
(SIN 01408)
.2301M68P01
35-400, 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 instructions for the seal have not changed. Refer to the GEnx-1B EM, 72-00-02, DISASSEMBLY 004, Subtask 72-00-02-030-366.
(2)Installation instructions for the seal have not changed. Refer to the GEnx-1B EM, 72-00-02, ASSEMBLY 002, Subtask 72-00-02-430-731.