# General Electric Service Bulletin CF34-8C: No revision named

- Rights: © General Electric Company. Filed by the FAA in regulations.gov docket FAA-2019-0394, the docket of AD 2019-22-05. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [General Electric Service Bulletin CF34-8C](https://openairdocs.org/service-documents/ge/cf34-8c.md)
- Title as filed: GE SB CF34-8C-SB-75-0020-r04
- Pages: 23
- PDF: https://openairdocs.org/files/sha256/44/dc/44dc5fd17c502f0e4a67d310b13e6fdd7f27a0ccf7af20bb665eafab0540e190
- Page: https://openairdocs.org/service-documents/ge/cf34-8c/file/44dc5fd17c50

## Text

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### Page 1

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
1 of 23
CF34-8C SERVICE BULLETIN - 75-0020 R04 Revised:05/10/2019
SB 75-0020 R04 AIR - ECS LH AND RH DUCTING INSTALLATION
(75-00-01) - REPETITIVE INSPECTION OF OBV FITTINGS AND OBV
SYSTEM LINKS
Issued:
02/05/2018
GE Designated: -CONFIDENTIAL-
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 part.
This technical data is considered subject to the Export Administration
Regulations (EAR) pursuant to 15 CFR Parts 730-774. Transfer of this
data by any means to a Non-U.S. Person, whether in the United States or
abroad, without the proper U.S. Government authorization (e.g.,
License, exemption, NLR, etc.), is strictly prohibited.
GEAE authorizes the Federal Aviation Administration to incorporate this
document by reference in an Airworthiness Directive.
Copyright (2019) General Electric Company, U.S.A.
TRANSMITTAL INFORMATION
REVISION 4 TO SERVICE BULLETIN 75-0020
Revision 4 is issued to update paragraphs 1.,  andPLANNING INFORMATION
2., .MATERIAL INFORMATION
Revision 3 was issued December 14, 2018. Revision 2 was issued July 20,
2018. Revision 1 was issued April 05, 2018. The original was issued
February 05, 2018. Revision bars in the left margin identify changes.
1. PLANNING INFORMATION
A. Effectivity
* * * CF34-8C1/-8C5/-8C5A1/-8C5A2/-8C5A3/-8C5B1
This Service Bulletin is applicable to these CF34-8C engines:
*CF34-8C engines with more than 6,000 flight hours engine time since new
(ETSN) and with an operability bleed start valve [operability bleed valve
(OBV)] P/N , P/N , P/N , or P/N .4123T71P02 4123T71P03 4123T71P04 4123T71P05
The OBV and OBV system rod links are affected by this Service
Bulletin.

### Page 2

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
2 of 23
B. Description
This Service Bulletin introduces a repetitive inspection
threshold for engines with more than 6,000 flight hours ETSN to
inspect the OBV for fuel leakage and loose rosan fittings, all
the OBV system rod links for wear on the uniball, and fuel lines
for proper routing every 880 flight hours.
C. Compliance
Category 2
GE recommends that you do this Service Bulletin for engines with
more than 6,000 flight hours ETSN and that had either initial
inspection performed as specified in CF34-8C S/B  or75-0019
repeat inspection performed as specified in this Service
Bulletin.
GE recommends that you do this Service Bulletin as soon as
possible without effect on revenue service but before 880 flight
hours from the Revision 3 issue date of this Service Bulletin. Do
again this inspection at intervals of every 880 flight hours or
less.
Impact A
This recommendation is to address a condition that may affect
Flight Safety.
NOTE:This Service Bulletin can be done on wing or 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
operator's fleet.
D. Concurrent Requirements
None.
E. Reason
(1) Objective:
To reduce significant events and reduce the potential for fuel leaks and
undercowl fire events.
(2) Condition:
There have been two undercowl fire events due to OBV separated fittings.
Refer to the All Operator's Wire (AOW) 17-CF34-006.
In addition, the fleet recently experienced a fitting detachment without a
fire event.
(3) Cause:
Most likely root cause indicates that the progressive wear on the OBV
manifold support links promotes resonance loads that exceed the normal
forces on the port/fitting threads, leading to OBV housing fuel port thread
wear.
(4) Inspection:
This repetitive inspection is for the CF34-8C engines with more than 6,000
flight hours ETSN OBV systems to identify possible loose or leaking OBV
fittings, worn system rod links, or improper routing of the fuel lines.
NOTE:This repetitive inspection is a containment plan only. The final
improvement will be provided by a future Service Bulletin.
(5) Substantiation:
Substantiation is by fleet experience.
F. Approval

### Page 3

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
3 of 23
The data contained in this Service Bulletin has been reviewed by
the FAA or authorized entity representing the FAA and the
repair(s) and modification(s) herein comply with the applicable
Aviation Regulations and are APPROVED for installation in the
model(s) listed in this Service Bulletin.
G. Manpower
After you get access to the OBV, you will need approximately 0.75
man-hour to do the inspection portion of this Service Bulletin.
H. Weight and Balance
Weight and balance are not changed.
I. References (Use the latest version of these documents)
All Operator's Wire (AOW) 17-CF34-006
Bombardier CRJ700/900/1000 Aircraft Maintenance Manual (AMM)
GEK 9250, Commercial Engine Standard Practices Manual (SPM)
Deleted
GEK 105091-1, CF34-8C Line Maintenance Manual (LMM)
GEK 105092, CF34-8C Illustrated Parts Catalog (IPC)
CF34-8C S/B , POWERPLANT - General (71-00-00) -71-0000
Consolidated On-Wing Inspection Recommendations and Servicing
Tasks List
CF34-8C S/B , AIR - Environmental Control System75-0014
(75-00-01) - Introduction of Redesigned Bleed Air Manifold and
Associated Components for the Operability Bleed Start Valve
CF34-8C S/B , AIR - ECS LH and RH Ducting Installation75-0019
(75-00-01) - Inspection of OBV Fittings and OBV System Links
CF34-8C S/B , AIR - Operability Bleed Valve (75-30-03) -75-0023
Rework of Operability Bleed Start Valve VIN 5080046-101 (P/N
4123T71P04) to VIN 5080046-102 (P/N 4123T71P05)
J. Publications Affected
None.
K. Interchangeability
Not applicable.
L. Software Accomplishment Summary
Not applicable.
2. MATERIAL INFORMATION
A. Material - Price and Availability
(1) Parts necessary to do this Service Bulletin:
None.
(2) Other Spare Parts:
Part Number
Qty/
Eng Part Name
Unit ($)
Price 
Pkg
Qty
Lead
Time
Days
4123T71P05* (1) Valve, Operability
Bleed Start
Quote (1) Quote
AS1895-1-225 (AR) Coupling, Single
Latch V-Retainer
475.00 (1) 5
AS1895-7-225 (AR) Seal, E 279.00 (1) 5
B0308015** (AR) Bearing, Rod End NP (-) --
B0202019-11** (AR) Washer, Locking NP (-) --
CN627-0082-201** (AR) Bush NP (-) --
CN627-0045-201 ** (AR) Bush NP (-) --

### Page 4

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
4 of 23
J1220G06 (AR) Clamp, Cushioned 8.50 (50) 5
TA027000H006WC (AR) Clip-P 35.75 (1) 5
NP = Not Provisioned
NOTE:Prices are provided for planning purposes and are subject to change.
*Part not supplied by GE Engine Services Distribution L.L.C. To procure
parts, contact the following:
Parker Aerospace
Aircraft On Ground (AOG)
U.S.A.
Phone: +1(949)809-8200
Commercial Purchase Order/Customer Service/Technical Inquiry
USA Phone: +1(949)809-8200
E-mail: CRC@parker.com
Fax: +1(949)272-3255
Commercial Spares Quotes (RFQ)
USA Phone: +1(949) 809-8200
E-mail: aerospacerfq@parker.com
**Part not supplied by GE Engine Services Distribution L.L.C. To procure
parts, contact the following:
Bombardier
E-mail: AOG@aero.bombardier.com
24/7 AOG phone: +1-844-272-2720
(3) Consumables:
None.
B. Industry Support Information
None.
C. Configuration Chart
None.
D. Parts Disposition
Discard unserviceable or worn rod ends, bushings, or washers.
Send the unserviceable OBV for repair to the following address:
Parker Aerospace
Aircraft On Ground (AOG)
U.S.A. Phone: +1(949)809-8200
Commercial Purchase Order/Customer Service/Technical Inquiry
USA phone: +1(949)809-8200
E-mail: CRC@parker.com
Fax: +1(949)272-3255
Commercial Spares Quotes (RFQ)
USA phone: +1(949) 809-8200
E-mail: aerospacerfq@parker.com
E. Tooling - Price and Availability
None.
3. ACCOMPLISHMENT INSTRUCTIONS
A. General
(1) Before you start this procedure, read the assembly and disassembly
techniques section. Refer to GEK 9250, 70-10-00, ASSEMBLY AND DISASSEMBLY
TECHNIQUES.

### Page 5

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
5 of 23
(2) Do a visual inspection of all the engine parts that you can see when you do
maintenance. Examine all parts that are removed and that you will install
again. Examine all engine parts that are not removed, but that you can see
during maintenance. Refer to CF34-8C-AL S/B .71-0000
(3) If the engine is on wing, do the job setup. Refer to the Bombardier
CRJ700/900/1000 AMM, 75-31-01, TASK 75-31-01-000-801.
B. Inspection
(1) Do not remove the OBV or the fuel lines around the OBV and do(Figure 1) 
a detailed visual inspection of all the OBV fittings.
(2) Refer to the Table 1 below for the inspection details, unserviceable
criteria, and actions.
Table 1. OBV Inspection
Inspection Unserviceable Criteria Action
Fuel leakage from all
the OBV fittings.
A clean trail through the
normally stained/dirty rosan
ring is an indicative of fuel
leakage.
Fuel wetting observed in the
rosan ring flange or port
joint. Refer to  Figure 1.
Replace the OBV immediately.
Refer to the Bombardier
CRJ700/900/1000 AMM, 75-31-01,
REMOVAL/INSTALLATION or GEK
105091-1, 75-00-00, SPECIAL
PROCEDURES 007 for the
removal instructions and
route it for repair.
All OBV fittings
wiggle check.
Relative movement observed
between the rosan fitting and
OBV housing when the B-nut is
wiggled with forefinger and
thumb pressure. Refer to 
 Figure 2.
Replace the OBV immediately.
Refer to the Bombardier
CRJ700/900/1000 AMM, 75-31-01,
REMOVAL/INSTALLATION or GEK
105091-1, 75-00-00, SPECIAL
PROCEDURES 007 for the
removal instructions and
route it for repair.
(3) Document the findings in the Inspection Chart Form  and send(Figure 9)
the results to GE. Refer to step 3.B.(8).

### Page 6 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
NOTE:
(*) THE ROSAN FITTING IS THE
THREADED INSERT ON EACH
OF THE OBV FUEL PORTS.
DRAIN PORT
INSPECTION AREA
RETURN PORT
INSPECTION AREA
OBV
SUPPLY PORT
INSPECTION AREA
*ROSAN RING
ROSAN
FITTING
ASSEMBLY
(TYPICAL)
5049111-00
OBV Fuel Leakage Inspection
Figure 1
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  transfer of this data to a Non-US  Person, without USG  6 of 23
authorization, is strictly prohibited.

### Page 7 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
OBV FITTING
OBV
HOUSING-
SUPPLY FITTING INSPECTION
OBV  - OBV FITTING
HOUSING
RETURN FITTING INSPECTION
OBV
HOUSING
OBV FITTING
5049112-00
OBV Fittings Wiggle Check
Figure 2
(4) If the OBV is unserviceable, remove and replace it with a serviceable OBV.
Refer to the Bombardier CRJ700/900/1000 AMM, 75-31-01, REMOVAL/INSTALLATION
Or GEK 105091-1, 75-00-00, SPECIAL PROCEDURES 007.
(5) Do an inspection of the bleed air manifold (OBV plenum assembly) (01-430,
01-430A, 01-430B, or 01-430C, 75-00-01, Figure 3) link rod assemblies and
their attaching hardware. Do not disassemble the link rod assemblies while
you do the inspection and do as follows:
(a) Remove the single latch V-retainer coupling (01-410, 75-00-01, Figure
4, Sheet 5) from the OBV plenum assembly (01-430, 01-430A, 01-430B, or
01-430C) side only. Make sure that the E-seal (01-420) stays installed.
(b) Do a visual inspection of the link rod assemblies (01-310, 01-310A,
01-450, 01-560A, 01-560B, and 01-570B, 75-00-01, Figure 4, Sheet 1,
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  7 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 8

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
8 of 23
Sheet 2, and Sheet 3) for an unusual condition. Refer to Figure 5.
(c) Use finger force (thumb and index) to do an inspection of the two ends
of the support links for loose or missing uniballs. Make sure that the
link rod assemblies (01-310, 01-310A, 01-450, 01-560A, 01-560B, and
01-570B, 75-00-01,  Sheet 1, Sheet 2, and Sheet 3) show noFigure 4,
radial displacement. Refer to  and  for details.Figure 3 Figure 4
(d) If there is movement of the installed rod end, remove the rod end and
do a check for serviceability criteria as follows:
1 Push the right side of the rod end and measure the left side rod end
uniball proud dimension.
2 Push the left side of the rod end and measure the right side rod end
uniball proud dimension.
NOTE:Unacceptable wear is present if the uniball can be displaced
radially by finger force and the face of the rod end uniball is
observed to protrude 0.020 inch (0.51 mm) or less from the adjacent
parallel face of the rod end  and (Figure 3 Figure 4, Sheet
4).

### Page 9 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
RADIAL  LINK ROD
DISPLACEMENT  ASSEMBLY
OBV PLENUN ASSEMBLY
(01-430)
OR
(01-430A)
OR
(01-430B)
OR
(01-430C)
NOTE:
ALL IPC REFERENCES FROM  TYPICAL
75-00-01 UNLESS SPECIFIED
DIFFERENTLY.  5049113-00
Link Rod Assembly
Figure 3
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Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  9 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 10 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
LINK ROD ASSEMBLY
(01-310)
OR
(01-310A)
NOTE:
ALL IPC REFERENCES FROM
75-00-01 UNLESS SPECIFIED
DIFFERENTLY.
5049114-00
Link Rod Assembly Inspection
Figure 4 (Sheet 1)
GE PROPRIETARY INFORMATION - Not to be used, disclosed  to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  10 of 23
transfer of this data to a Non-US  Person, without  USG
authorization, is strictly prohibited.

### Page 11 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
LINK ROD ASSEMBLY
(01-450)
LINK ROD ASSEMBLY
(01-560A)  LINK ROD ASSEMBLY
(01-570B)
NOTE:
ALL IPC REFERENCES FROM
75-00-01 UNLESS SPECIFIED
DIFFERENTLY.
(PRE-CF34-8C S/B 75-0014)  5049115-01
Link Rod Assembly Inspection
Figure 4 (Sheet 2)
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  11 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 12 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
LINK ROD ASSEMBLY
(01-450)
LINK ROD
ASSEMBLY
(01-560B)
© LINK ROD
ASSEMBLY
(01-560B)
(POST-CF34 8C S/B 75-0014)
NOTE:  (TYPICAL)
ALL IPC REFERENCES FROM  (3 LOCATIONS)
75-00-01 UNLESS SPECIFIED
DIFFERENTLY.  5049120-01
Link Rod Assembly Inspection
Figure 4 (Sheet 3)
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  transfer of this data to a Non-US  Person, without USG  12 of 23
authorization, is strictly prohibited.

### Page 13 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
ROD END
*0.020 MINIMUM
(0.51)
*0.020 MINIMUM
(0.51)
ROD END
UNIBALL
NOTES:
1. DIMENSIONS ARE IN INCHES WITH
MILLIMETERS IN PARENTHESES.
2. (*) DIMESIONS EQUAL OR LESS THAN 0.020 (0.51) ARE NOT PERMITTED.
DIMENSIONS MORE THAN 0.020 (0.51) ARE PERMITTED.  5049116-00
Link Rod Assembly Inspection
Figure 4 (Sheet 4)
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  13 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 14 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
(01-410)  V-RETAINER  COUPLING  (01-420)  E-SEAL  (01-420)  E-SEAL  COUPLING  V-RETAINER  (01-410)
OBV PLENUM
ASSEMBLY
(01-430)
OR
(01-430A)
OR
(01-430B)
OR
(01-430C)
10TH STAGE
DUCTING
NOTE:
ALL IPC REFERENCES FROM
75-00-01 UNLESS SPECIFIED
DIFFERENTLY.  5061727-00
Link Rod Assembly Inspection
Figure 4 (Sheet 5)
(e) If one or more link rod assemblies (01-310, 01-310A, 01-450, 01-560A,
01-560B, and 01-570B, 75-00-01, Figure 4, Sheet 1, Sheet 2, and Sheet
3) or their attaching hardware have wear beyond the limits specified in
steps 3.B.(5) (c) and 3.B.(5) (d), remove and replace the damaged
hardware with a serviceable part, one at a time. Refer to Figure 5 and
GEK 105091-1, 75-00-00, SPECIAL PROCEDURES 010, Subtask
75-00-00-051-029 and Subtask 75-00-00-051-030 for the removal
instructions, Subtask 75-00-00-451-024 and Subtask 75-00-00-451-027 for
the installation instructions, and Subtask 75-00-00-350-006 for the rod
end bearing replacement instructions.
NOTE:Some of the link rod assembly catalog sequence numbers (CSNS) could
not be mentioned in GEK 105091-1, 75-00-00, SPECIAL PROCEDURES 010.
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
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transfer of this data to a Non-US Person, without  USG
authorization, is strictly prohibited.

### Page 15

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Date Printed:
2019/06/07
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
others or reproduced without the express written consent of
GE. Technical data is considered ITAR and/or EAR controlled;
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.
Page
15 of 23
For those cases, the parts identified with the base CSNs or part
numbers are used for the applicable removal/installation instructions
and must be used in accordance with GEK 105092, CF34-8C IPC.
NOTE:Before you disassemble the removed link rod assembly, the total length
from rod end to rod end must be measured.
NOTE:The inspection for serviceability of the two rod ends must be done
from the link rod assemblies.
(f) In order not to use alignment tooling and reduce the adjustment cycle,
it is recommended to measure the removed link rod assemblies (01-310,
01-310A, 01-450, 01-560A, 01-560B, and 01-570B, 75-00-01, Figure 4,
Sheet 1, Sheet 2, and Sheet 3) before disassembly, set-up the length as
the baseline for new part setup, count the threads, and measure the rod
end uniball center to center length.
NOTE:If no serviceable link rod assembly hardware is available for the
replacement, the engine can be returned to service for an additional
50 flight cycles if the OBV rosan rings and fittings are examined for
fuel leaks and looseness as in Table 1. The inspection must be done at
customer's convenience, but it must be done once each day.
(g) Document the findings in the Inspection Chart Form  and(Figure 9)
send the results to GE. Refer to step 3.B.(8).
(h) For replaced links and if the links passed the inspections above only,
do an inspection of the rod end assemblies for alignment/twisting.
Refer to  and do as follows:Figure 10
NOTE:The rod end assembly is capable of rotation about the rod end axis
(twist) as shown in Figure 10.
1 Use hand force to turn the rod ends.
2 Do an inspection of the rod end alignment to make sure that the rod
end surfaces do not touch the bushings. If realignment is necessary,
use hand force to align the rod end relative to the bushings as
shown in Figure 10.
(i) Make sure that the E-seal (01-420, 75-00-01,  Sheet 5) isFigure 4,
installed.
(j) Install again the single latch V-retainer coupling (01-410) to the OBV
plenum assembly (01-430, 01-430A, 01-430B, or 01-430C) side only.
(k) Torque the single latch V-retainer coupling (01-410) to 110.4 to 129.6
lb in. (12.4 to 14.6 Nm).

### Page 16 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
ROD END UNIBALL
90915
SERVICEABLE ROD END  WORN ROD END
ROD END
UNIBALL
SERVICEABLE ROD END  WORN ROD END
5049117-00
Serviceable and Worn Rod Ends
Figure 5 (Sheet 1)
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
GE. Technical data is considered ITAR and/or EAR controlled;  16 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 17 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
THE ROD END FACE IS
NOT IN CONTACT WITH
THE BRACKET FACES.
THE ROD END FACE IS  THE ROD END IS
COMPLETELY IN  CORRECTLY CENTERED IN
CONTACT WITH THE OBV  THE BRACKET. NO WEAR
PLENUM ASSEMBLY.  MARKS.
THE BEARING
BALL IS VISIBLE IN ONE
SIDE ONLY.
UNUSUAL  TYPICAL
CONDITION  CONDITION
5061252-00
Serviceable and Worn Rod Ends
Figure 5 (Sheet 2)
(6) Make sure that the OBV tubes [fuel drain 1 pipe assembly (01-310,
71-71-01), OBV muscle fuel supply tube (01-170, 73-21-05), and OBV muscle
fuel return tube (01-130)] attaching hardware is correctly installed. Refer
to Figure 11 and do as follows:
(a) With hand force, try to move the OBV tubes in all directions, near the
attachment points on the clip-P (P-clip) (01-320, 71-71-01) and
cushioned clamps (clamps) (01-140 and 01-180, 73-21-05).
(b) If the P-clip (01-320, 71-71-01) and clamps (01-140 and 01-180,
73-21-05) are correctly installed, no sliding across the OBV tubes must
occur. If sliding occurs, then torque again the 12-point bolt (01-340,
71-71-01) that attaches the P-clip (01-320) and the 12-point bolts
(01-150 and 01-190, 73-21-05) that attach the clamps (01-140 and
01-180, 73-21-05) to 32.2 to 37.8 lb in. (3.6 to 4.2 Nm).
(c) The P-clip (01-320, 71-71-01) and clamps (01-140 and 01-180, 73-21-05)
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  17 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 18 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
must be firmly attached. If they are not firmly attached, torque again
the 12-point bolt (01-340, 71-71-01) that attaches the P-clip (01-320)
and the 12-point bolts (01-150 and 01-190, 73-21-05) that attach the
clamps (01-140 and 01-180) to 32.2 to 37.8 1b in. (3.6 to 4.2 Nm).
(d) If after you torque the 12-point bolt (01-340, 71-71-01) and 12-point
bolts (01-150 and 01-190, 73-21-05) the sliding or looseness continues,
replace the P-clip (01-320, 71-71-01) and clamps (01-140 and 01-180,
73-21-05). After you replace the P-clip (01-320, 71-71-01) and clamps
(01-140 and 01-180, 73-21-05), torque the 12-point bolt (01-340,
71-71-01) and 12-point bolts (01-150 and 01-190, 73-21-05) to 32.2 to
37.8 lb in. (3.6 to 4.2 Nm).
(e) Document if there is looseness, a missing P-clamp, or another unusual
condition in the Inspection Chart Form (Figure 9).
FIGURE DELETED
99de0011
Deleted
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  18 of 23
transfer of this data to a Non-US  Person, without USG
authorization, is strictly prohibited.

### Page 19 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
Figure 6
FIGURE DELETED
99de0011
Deleted
Figure 7
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  19 of 23
transfer of this data to a Non-US Person, without USG
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### Page 20 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
FIGURE DELETED
99de0011
Deleted
Figure 8
(7) If the engine is on wing, put the aircraft back to its usual condition.
Refer to the Bombardier CRJ700/900/1000 AMM, 75-31-01, TASK
75-31-01-400-801, Step 5 (Close Out).
(8) Send a copy of the Inspection Chart Form (Figure 9) to the GE Product
Support Engineering (PSE):
* Eric Perez (Eric.Perez@ge.com).
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
GE. Technical data is considered ITAR and/or EAR controlled;  20 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 21 (OCR)

CF34-8C Service Bulletins (SBS)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
INSPECTION CHART
ENGINE SERIAL NUMBER:  TIME SINCE NEW (TSN):
AIRCRAFT REGISTRATION:  CYCLES SINCE NEW (CSN):
POSITION:  DATE:
DEV SN:
LEAKAGE TRACES IN THE  SUPPLY  RETURN  DRAIN
OBV PORT JOINTS FOUND?  FITTING  FITTING  FITTING
YES
NO
OBV FUEL FITTING FOUND LOOSE (WIGGLING)?
YES
NO
ROD END  OTHER
WERE LINK ROD ASSEMBLIES WORN?  MANIFOLD CASE  PLENUM  SPECIFY
FRONT RIGHT
FRONT LEFT
REAR
10"" STAGE DUCT
INSPECTION PERFORMED BY:
ADDITIONAL COMMENTS:
WAS THE P-CLAMP MISSING?
WAS LOOSENESS ON THE P-CLAMP DETECTED?
WAS ANOTHER UNUSUAL CONDITION DETECTED?
NOTE:
WRITE N/A WHEN THE REQUEST IS NOT APPLICABLE TO YOUR ENGINE CONFIGURATION.  5049123-01
Inspection Chart Form
Figure 9
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  21 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

### Page 22 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
TWISTING
ABOUT ITS
ROD END
AXIS
EXAMPLE OF
UNDESIRED
ROD  TWIST, ROD END
END  CONTANTING
BUSHING
CORRECT TWIST
OF ROD END,  BUSHINGS
CENTERED
BETWEEN  UNDESIRED ALIGNMENT
BUSHINGS
CORRECT ALIGNMENT
5056111-00
Twisting of the Rod Ends (Pre/Post-CF34-8C S/B 75-0014)
Figure 10
GE PROPRIETARY INFORMATION - Not to be used, disclosed to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  22 of 23
transfer of this data to a Non-US  Person, without USG
authorization, is strictly prohibited.

### Page 23 (OCR)

CF34-8C Service Bulletins (SBs)
SB 75-0020 R04 AIR - ECS LH and RH Ducting Installation (75-00-01) - Repetitive
Inspection of OBV Fittings and OBV System Links
OBV MUSCLE
FUEL
RETURN
TUBE
(01-130)
OBV MUSCLE
OBV.  FUEL SUPPLY
TUBE
(01-170)
FUEL
-DRAIN 1 PIPE
ASSEMBLY
(01-310,
71-71-01)
P-CLIP
CLAMP  (01-320,
(01-440, 75-41-01)  71-71-01)
CLAMP
(01-140)
C-SUMP TUBE
CLAMP
(01-180)
--CLAMP
(01-140)
CLAMP  -- CLAMP
(01-335, 71-71-01)  (01-140)
CLAMP
(01-140)  * CLAMP
(01-180)
CLAMP
(01-180)
NOTE:
ALL IPC REFERENCES FROM
73-21-05 UNLESS SPECIFIED
DIFFERENTLY.  5061251-00
Clamps of OBV Tubes
Figure 11
GE Designated: - CONFIDENTIAL Subject to the restrictions on the media
GE PROPRIETARY INFORMATION - Not to be used, disclosed  to
Date Printed:  others or reproduced without the express written consent of  Page
2019/06/07  GE. Technical data is considered ITAR and/or EAR controlled;  23 of 23
transfer of this data to a Non-US Person, without USG
authorization, is strictly prohibited.

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