# Boeing Alert Service Bulletin 737-71A1462: U.S. DOT/FAA - Service Bulletin

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- Document: [Boeing Alert Service Bulletin 737-71A1462](https://openairdocs.org/service-documents/boeing/737-71a1462.md)
- Title as filed: U.S. DOT/FAA - Service Bulletin
- Pages: 62
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### Page 1

August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 1o f6 2
ALERT ALERT
Commercial
Airplane
Group 737
ALERTALERT
Service Bulletin
Number: 737-71A1462
Date: August 29, 2002
Revision 3 May 20, 2004
ATA System: 7121
SUBJECT: POWER PLANT - Engine Mounts - Aft Engine Mount, Link Assembly, Hanger Fitting,
Inspection, Correction and Identification of Parts
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET
Copyright © 2002 The Boeing Company
Unpublished Work - All Rights Reserved
Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable
subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.
This document includes proprietary information owned by The Boeing Company and/or one or more third
parties. Treatment of the document and the information it contains is governed by contract with Boeing. For
more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, BBJ, DC-8, DC-9,
DC-10, MD-10, MD-11, MD-80, MD-88, MD-90, and the red-white-and-blue Boeing livery are all trademarks
owned by The Boeing Company; and no trademark license is granted in connection with this document unless
provided in writing by Boeing.

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ALERT ALERT
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Table of Contents
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
Table of Contents
R e v i s i o n T r a n s m i t t a l S h e e t .........................................5
S u m m a r y .............................................7
1 . P L A N N I N G I N F O R M A T I O N ..................................... 1 1
A . E f f e c t i v i t y ............................................ 1 1
1 . A i r p l a n e s ......................................... 1 1
2 . S p a r e s A f f e c t e d ...................................... 2 4
B . C o n c u r r e n t R e q u i r e m e n t s................................... 2 5
C . R e a s o n ............................................ 2 5
D . D e s c r i p t i o n ........................................... 2 8
E . C o m p l i a n c e ........................................... 2 8
F . A p p r o v a l............................................ 2 9
G . M a n p o w e r ........................................... 3 0
H . W e i g h t a n d B a l a n c e C h a n g e s................................. 3 1
I . E l e c t r i c a l L o a d D a t a...................................... 3 1
J . R e f e r e n c e s ........................................... 3 1
1 . E x i s t i n g D a t a : ....................................... 3 1
2. Data supplied with this Service Bulletin: . . . . . . . . . . . . . . . . . . . . . . . . . 31
3. Installation Drawings Used in the Preparation of this Service Bulletin: . . . . . . . . . . 31
4 . P r o c e s s D a t a : ....................................... 3 1
K . P u b l i c a t i o n s A f f e c t e d ...................................... 3 2
L . I n t e r c h a n g e a b i l i t y a n d I n t e r m i x a b i l i t y o f P a r t s......................... 3 2
2 . M A T E R I A L I N F O R M A T I O N ..................................... 3 3
A . M a t e r i a l - P r i c e a n d A v a i l a b i l i t y ................................. 3 3
B . I n d u s t r y S u p p o r t I n f o r m a t i o n .................................. 3 3
C . P a r t s N e c e s s a r y F o r E a c h A i r p l a n e.............................. 3 3
1 . K i t s / P a r t s : ......................................... 3 3
2 . P a r t s a n d M a t e r i a l s S u p p l i e d b y t h e O p e r a t o r :...................... 3 3
3 . P a r t s M o d i f i e d a n d R e i d e n t i f i e d : ............................. 3 3
4 . P a r t s R e m o v e d a n d N o t R e p l a c e d : ............................ 3 4
D . P a r t s N e c e s s a r y t o C h a n g e S p a r e s.............................. 3 4
E . S p e c i a l T o o l i n g - P r i c e a n d A v a i l a b i l i t y ............................. 3 4
F . S p e c i a l T o o l i n g N e c e s s a r y t o d o t h i s S e r v i c e B u l l e t i n ..................... 3 4
3 . A C C O M P L I S H M E N T I N S T R U C T I O N S ............................... 3 5
A . G E N E R A L I N F O R M A T I O N .................................. 3 5
B. WORK INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
FIGURE 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) INSTALLATION
I N S P E C T I O N....................................... 3 9
FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
I N S P E C T I O N ...................................... 4 1
FIGURE 3: AFT ENGINE MOUNT, CENTER LINK (WITH POCKETS) INSTALLATION INSPECTION 45
FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
I N S P E C T I O N....................................... 4 7
F I G U R E5 : H A N G E R F I T T I N G , A D D I D E N T I F I C A T I O N M A R K S .................... 5 1
FIGURE 6: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS), ADD
I D E N T I F I C A T I O N M A R K S................................ 5 2

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Table of Contents
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 7: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS), ADD
I D E N T I F I C A T I O N M A R K S ................................. 5 3
FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
I N S T A L L A T I O N......................................5 4
FIGURE 9: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) AND ENGINE
I N S T A L L A T I O N .....................................5 8
APPENDIX A: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY REPORT FORM . . . . . . . . . . 62

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ALERT ALERT
Commercial
Airplane
Group 737
ALERTALERT
Service Bulletin
Number: 737-71A1462 Revision Transmittal Sheet
Date: August 29, 2002
Revision 3 May 20, 2004
ATA System: 7121
SUBJECT: POWER PLANT - Engine Mounts - Aft Engine Mount, Link Assembly, Hanger Fitting,
Inspection, Correction and Identification of Parts
This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
Federal Aviation Administration (FAA) Airworthiness Directive AD 2003-03-01, Amendment 39-13025, is related
to this service bulletin.
More work is necessary for airplanes that have not had an engine change since the new airplane was received
from Boeing, do the Part 1 Inspection procedures unless the Part 1 Inspection or the Part 2 Part Mark
procedures have been done.
No more work is necessary on airplanes that have had an engine change since the new airplane was received
from Boeing, have done the Part 1 Inspection and Part 2 Part Mark procedures.
No airplanes have been added by Revision 3 of this service bulletin. The Revision 2 of this service bulletin
included the airplanes effectivity that could be affected by this service bulletin.
REASON FOR REVISION
Revision 3 is sent to tell operators that for the airplanes that have not had an engine change since the new
airplane was received from Boeing, it is possible that some center links were incorrectly installed in an aft engine
mount before the airplane was delivered. Before this revision, inspection of the aft engine mounts was
necessary only for the airplanes that had an engine change after the new airplane was received from Boeing.
With the release of Revision 3 of this service bulletin, the Part 1 Inspection is applicable to all airplanes given in
the effectivity of this service bulletin.
1. On Summary section, Background, paragraph 1.C., Reason and paragraph 1.D., Description, more
information has been added to include the airplanes that have not had an engine change since the new
airplane was received from Boeing.
2. On Summary section, Background, paragraph 1.C., Reason and paragraph 1.J., References, a new
paragraph has been added to show the Boeing Service Related Problem information that is related to this
service bulletin.

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3. On Summary section and paragraph 1.E., Compliance information, the paragraphs about Part 1 have been
changed to include airplanes that have not had an engine change since the new airplane was received from
Boeing. The paragraphs about Part 2 have been changed to give more information. All engine installed
after 90 days has been changed to during the subsequent engine changes done after 90 days.
4. On paragraph 1.A., Planning Information, Effectivity, a group condition table has been added.
5. On paragraph 2.B., Industry Support Information, a warranty statement has been added for airplanes that
have not had an engine change since the new airplane was received from Boeing.
6. On paragraph 2.C.3., Parts Modified and Reidentified table and Figure 5 work instruction table, Step 2, the
part numbers for the hanger fitting 310A2031-23 and the hanger fitting assembly 310A2031-24 have been
added.
7. On paragraph 3.B.,Part 1,2., the work instruction step has been changed to delete information about
airplanes that have had an engine change after the airplane was delivered and during subsequent engine
installations. The changed Step 2 make the step applicable to all airplanes and the same compliance
information is already shown in the Compliance paragraphs.
8. On paragraph 3.B.,Part 1,3.e. and Part 2,1., the work instruction steps have been added for airplanes if do
or not do the Part 1 and Part 2 Work Instructions at the same time.
9. On paragraph 3.B.,Part 1,4., the work instruction step has been added for airplanes that have found the aft
engine mounts correctly installed.
10. On paragraph 3.B.,Part 2,4., the work instruction step has been added to close access. The note on the
left, right and aft markings has been changed to a Caution note.
11. Figures 1 and 3 have been changed to show the left side view to agree with the note that said the best view
is from the left side. The view was shown from the right side of the aft engine mount.
12. Figures 2 and 4 have been changed to delete the assembly and installation steps Steps 9 through 12. The
same assembly and installation steps have been moved to the new Figures 8 and 9 for airplanes that
possibly do Part 1 Correction and Part 2 part mark work instructions at the same time.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location
of important changes.
Pages with no vertical lines have no important changes.
REVISION HISTORY
Original Issue: August 29, 2002
Revision 1: November 7, 2002
Revision 2: May 29, 2003
Revision 3: May 20, 2004

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ALERT ALERT
Commercial
Airplane
Group 737
ALERTALERT
Service Bulletin
Number: 737-71A1462 Summary
Date: August 29, 2002
Revision 3 May 20, 2004
ATA System: 7121
SUBJECT: POWER PLANT - Engine Mounts - Aft Engine Mount, Link Assembly, Hanger Fitting,
Inspection, Correction and Identification of Parts
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN
PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE
BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE
BULLETIN TO THE NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
Part 1 of this service bulletin was initially prepared to give instructions for operators to do a one-time inspection
of all airplanes that have had an engine change since the airplane was delivered. It is necessary to do the
inspection on all subsequent engine changes unless Part 2 marked engine mounts are installed.
In September 2003, an operator told Boeing that an airplane was found with a center link installed incorrectly
on an aft engine mount. The operator also told Boeing that the airplane had not had an engine change since
the new airplane was received from Boeing. As a result, it is necessary for airplanes that have not had an engine
change since the new airplane was received from Boeing to do the Part 1 inspection on each of the aft engine
mounts.
In October 2001, one operator told Boeing it was necessary to get clarification of manuals related to engine
mount assembly and installation. After the initial help from Boeing, the operator reported that the aft engine
mount center link assembly, P/N 310A2034-3, could have been reversed during overhaul assembly and
subsequently installed on airplanes. The operator inspected all airplanes that had engine installations since the
airplanes were delivered. Six reversed center links were found, which were immediately corrected. No damage
was reported after visual inspection of the aft mount and local engine attachment was completed.
The operator found that no anomalies were reported during the aft engine mount installations or during the
engine installations. It was found that some increase in force was necessary to install the pawl pins that attach
the aft engine mount to the engine.

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In December 2001, a second operator told Boeing about problems they had when they tried to close the thrust
reversers after engine replacement. Visual inspection showed gap differences between the thrust reverser aft
cowl and the primary exhaust sleeve on the two sides of the engine. The engine was lowered and the
subsequent inspection found a reversed center link assembly, P/N 310A2034-7. After the center link was
removed and installed correctly, the engine installation was completed satisfactorily.
Although the center link has an apparent symmetrical shape, there is a 0.2175 inch difference in the distances
between the center bearing and each side bearing. Also, the two spherical bearings installed at each end are
not the same bore diameter. The center link can be installed 180 degrees from the correct location (reversed)
and still be attached to the engine with the pawl pins in the correct location. More force can be necessary to
install the pins.
The reversed center link condition changes the structural loading of the aft engine mount interface with the
engine. If not corrected, failure of the aft engine mount can occur. Also, the reversed center link installation
causes a 0.174 inch displacement of the engine turbine rear frame to the right. The thrust reverser cowls are
not easily closed if this condition exist.
Part 2 gives instructions to install the permanent marks on the aft engine mount, which, if installed, releases
operators from the inspection requirements given in Part 1 of this service bulletin. The permanent marks identify
the correct installation position of the hanger fitting assembly and the center link assembly of the aft engine
mount.
Boeing Service Related Problem (SRP) 737-SRP-71-0035 is related to this service bulletin.
ACTION
Part 1, open the engine thrust reversers and get access to the aft engine mount. Do an inspection of the aft
engine mount to make sure that the center link assembly is correctly installed. If the center link assembly is
incorrectly installed, correct the installation and report this to Boeing.
Part 2, get access and remove the aft engine mount. Mark the aft face of the hanger fitting with “L”, “R” and AFT”
to identify the correct position for installation. Mark the aft face of the center link assembly with “L”, “R” and “AFT”
to identify correct position for installation. Install the aft engine mount.
EFFECTIVITY
737-600/700/700C/800/900 airplanes. See Service Bulletin (SB) Paragraph 1.A.1 for effectivity.
COMPLIANCE
Federal Aviation Administration (FAA) Airworthiness Directive AD 2003-03-01, Amendment 39-13025, is related
to this service bulletin.
Part 1, For airplanes that have had an engine change since the new airplane was received from Boeing, in 90
days or less from the initial release of SB 737-71A1462, Boeing recommends that operators do a one-time
inspection of the aft engine mount and make sure of the correct installation of the center link assembly unless
the mount is marked as given in the Part 2 of this service bulletin. If a reversed center link is found, the condition
must be corrected before the next flight. If only one engine on an airplane has been replaced, it is only
necessary to do an inspection of that engine.

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Part 1: For airplanes that have not had an engine change since the new airplane was received from Boeing, in
90 days or less from the Revision 3 release of SB 737-71A1462, Boeing recommends that operators do a
one-time inspection of the aft engine mount to make sure of the correct installation of the center link assembly.
If a reversed center link is found, the incorrect condition must be corrected before the next flight. No more new
inspection is necessary if the aft engine mounts were inspected as shown in the initial, Revision 1 or Revision
2 of this service bulletin.
Part 1: For all subsequent engine changes on all airplanes, Boeing recommends operators do the Part 1
Inspection on each aft engine mount during each subsequent engine change until the marked aft engine mount
is installed.
Part 2: For all airplanes that have had or have not had an engine change, Boeing recommends that operators
do Part 2 part mark procedures if the engine mount is removed by the Part 1 Work Instructions, or during a
subsequent usual engine maintenance task when the engine removal is necessary.
Part 2: Boeing recommends that during the subsequent engine changes done after 90 days from the release of
SB 737-71A1462, Revision 2, install permanently marked aft engine mounts. All engine changes done in 90
days or less from the release of SB 737-71A1462, Revision 2, that do not have permanently marked aft engine
mounts, must have an inspection done as given in the Part 1 Inspection.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the inspection given in this service bulletin for airplanes that have
had an engine change since the new airplane was received from Boeing.
Boeing warranty remedies are available for airplanes in warranty as of October 9, 2003 if the airplanes have not
had an engine change since the new airplane was received from Boeing. Please refer to Paragraph 2.B.,
Industry Support Information.
MANPOWER
Manpower data for each engine position:
MATERIAL INFORMATION
None.
PART 1 Total Task Hours Elapsed Hours
Inspection 3.5 2.0
Removal and Installation 37.0 10.5
Inspection, Removal and
Installation
40.5 12.5
PART 2 Total Task Hours Elapsed Hours
Mark Aft Engine Mount 1.5 1.5

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FWD
FOR CORRECT INSTALLATION
INSPECT AFT ENGINE MOUNT
PART 1:
HANGER FITTING
LINK ASSEMBLY AND
MARK THE CENTER
PART 2:
V86787

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ALERT ALERT
Commercial
Airplane
Group 737
ALERTALERT
Service Bulletin
Number: 737-71A1462
Date: August 29, 2002
Revision 3 May 20, 2004
ATA System: 7121
SUBJECT: POWER PLANT - Engine Mounts - Aft Engine Mount, Link Assembly, Hanger Fitting,
Inspection, Correction and Identification of Parts
THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN
PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE
BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE
BULLETIN TO THE NEW OWNER.
1. PLANNING INFORMATION
A. Effectivity
1. Airplanes
Refer to Service Bulletin Index Document D6-19567 Part 3 for Airplane Variable Number, Line
Number, and Serial Number data.
This service bulletin is for the airplanes shown below.
Airplane models:
737-600 737-700 737-700C 737-800
737-900
IDENTIFICATION BY CUSTOMER, CUSTOMER CODE, GROUP AND VARIABLE NUMBER
GROUP CONDITION DESCRIPTION
1 - 737-600/-700/-700C/-800/-900 from Line 1 through
1277
1 737-600/-700/-700C/-800/-900 from Line 1 through
1277 airplanes that have had an engine change since
the new airplane was received from Boeing,
2 737-600/-700/-700C/-800/-900 from Line 1 through
1277 airplanes that have had no engine change since
the new airplane was received from Boeing,

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
AERO CONTRACTORS LTD (YAT)
1Y G 0 4 2
AIR ALGERIE (ALG)
1 YD101–YD107 YE301–YE305
AIR ASTANA (AKZ)
1 YA356–YA357 YC151
AIR BERLIN (BER)
1 YB201 YB203 YC051–YC070 YD151–YD155
AIR CHINA (BEJ)
1 YC941–YC951
AIR CHINA SOUTHWEST AIRLINES (XIN)
1 YC426–YC428 YE201–YE204
AIR EUROPA (ARE)
1 YC761–YC770 YC907 YD206–YD209
AIR MAURITANIE (MAR)
1 YA302
AIR NATIONAL GUARD (USK)
1 YG044 YG067 YG069
AIR PACIFIC (APC)
1 YA291 YC931–YC932
AIR SAHARA (SAQ)
1 YA253–YA254 YA731 YB204–YB205 YC901–YC902
AIR SENEGAL INTERNATIONAL (SNG)
1 YA683–YA684
AIR SEYCHELLES (ASY)
1 YA351
AIR SHAMROCK (SHI)
1Y G 0 1 6
ALASKA AIRLINES (ASA)
1 YA841–YA858 YD501–YD507
ALOHA AIRLINES (ALO)
1 YA607–YA608 YA610 YA614–YA615 YA627–YA629
YA732–YA733
AMERICAN AIRLINES (AAL)
1 YC801–YC877

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AMIRI FLIGHT (ABD)
1 YD410 YG023–YG026
ARAMCO ASSOCIATED COMPANY (RAS)
1 YB151–YB153 YG601–YG602
ASTRAEUS, LTD. (AUA)
1 YA671–YA672 YA681–YA682
ATA AIRLINES, INC. (AAT)
1 YD301–YD330
AUSTRALIAN WEDGETAIL PROGRAM (ZVI)
1 YG089 YG201
BANCO SAFRA (BNS)
1Y G 0 4 0
BB FIVE, INC (YIP)
1Y G 0 6 6
BBJ ONE (BBI)
1Y G 0 6 8
BEL AIR LIMITED (ULL)
1Y G 0 2 2
BELAVIA (ITU)
1 YD408
BNJ SALES COMPANY (BNJ)
1 YG031 YG033 YG035–YG036 YG038
BOEING (TBC)
1Y G 0 8 5
BOEING CAPITAL CORPORATION (ZMF)
1Y G 0 0 2
BOEING DEMONSTRATOR JET (BCJ)
1 YG001 YG071
BRAATHENS (BRT)
1 YA311 YA543 YA545 YA547–YA552
BRITANNIA AIRWAYS (BRI)
1 YD001–YD006
BWIA WEST INDIES AIRWAYS (TTA)
1 YC136–YC141 YJ001
CHARTWELL (CHP)
1Y G 0 1 7

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
CHINA AIRLINES (CHI)
1 YC571 YC574–YC583 YC589
CHINA EASTERN AIRLINES (CEA)
1 YB206 YB561–YB566
CHINA EASTERN AIRLINES WUHAN (WUH)
1 YD171–YD172
CHINA EASTERN YUNNAN AIRLINES (YUN)
1 YA811–YA814
CHINA SOUTHERN AIRLINES (GUN)
1 YJ671–YJ676
CHINA SOUTHWEST CHONGQING A/L (CHO)
1 YC981–YC983
CHINA XINJIANG AIRLINES (XIJ)
1 YA255–YA256 YA645 YA656
COMMONWEALTH OF AUSTRALIA (GAU)
1Y G 0 7 2 Y G 0 7 5
CONTINENTAL AIRLINES (CAL)
1 YA501–YA536 YC321–YC380 YD601–YD612 YJ501–YJ517
COPA AIRLINES (COP)
1 YA755–YA756 YA961–YA970
CYPRUS TURKISH AIRLINES (KTHY) (KHT)
1 YC467 YD021–YD022
DALLAH AL BARAKA (KAM)
1Y G 0 6 3
DELTA AIR LINES (DAL)
1 YC601–YC655 YC681–YC696
DOBRO LIMITED (DOB)
1Y G 0 0 8
DUBAI AIR WING (DAW)
1 YD402 YG007
EASYJET (EZY)
1 YB101–YB120 YB207
EIE EAGLE (EIE)
1Y D 4 0 9
EL AL ISRAEL AIRLINES (ELA)
1 YA881–YA882 YC405 YC591–YC593

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
EURALAIR HORIZONS (ERL)
1 YC701 YC703–YC704 YC707 YC727
EUROCYPRIA AIRLINES (ECY)
1 YC186
EVA AIR (EVA)
1Y G 0 8 3
EXCEL AIRWAYS (SBE)
1 YC111–YC113 YC903 YC906
EXCEL AIRWAYS-CYPRUS (XLC)
1 YC436–YC437
EXECUJET SWITZERLAND AG (XJT)
1Y G 0 1 1
EXECUTIVE JETS LIMITED (EJL)
1 YD407
FORD AIR SERVICES (FMC)
1 YA541–YA542
FUNAIR (FUN)
1Y G 0 2 7
FUTURA (FUA)
1 YC407 YC451 YC461–YC466
GAMA AVIATION LTD (GAV)
1Y G 0 1 0
GE CORPORATE AIR TRANSPORT (GEB)
1 YG003 YG012
GERMANIA (GER)
1 YA231 YA233 YA235–YA240 YA571–YA572
GOL AIRLINES (GOT)
1 YA201–YA202 YA232 YA234 YA241–YA242
YA321 YA602 YA605 YA611–YA612
YA646–YA648 YA650 YA657 YB202
YB271 YD256–YD257 YJ471–YJ472
HAINAN AIRLINES (HNA)
1 YA603–YA604 YA606 YC126–YC127 YC401
YC404 YC409 YC452 YC971–YC978
YD042–YD045 YD216
HAPAG-LLOYD FLUG (HAP)
1 YC001–YC030

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HELIOS AIRWAYS (HCY)
1 YC416–YC417
HI. HAMBURG INTERNATIONAL (HAU)
1 YA574–YA578 YB276
INTER AIRLINES (IAW)
1Y J 4 7 3 Y J 4 7 5
JET AIRWAYS (JPL)
1 YA609 YA621–YA622 YA734 YA751–YA754
YB181–YB183 YC402–YC403 YC731–YC741
JET AVIATION (JTA)
1 YD405 YG015 YG021
KENYA AIRWAYS (KEN)
1 YA635–YA636 YA641
KEVINAIR (KVN)
1Y G 0 3 7
KLM - ROYAL DUTCH AIRLINES (KLM)
1 YC781–YC793 YD531–YD534
KOREAN AIR (KAL)
1 YC441–YC448 YD121–YD126 YD541–YD547
L-3 COMMUNICATIONS (LCS)
1Y G 0 2 8
LAUDA AIR (LAL)
1 YB171–YB172 YC381–YC383 YE171–YE172
LIMITED BRAND INC. (LII)
1Y G 0 0 5
LINEAS AEREAS AZTECA (AZX)
1 YA601 YB501–YB502
LOWA CORPORATION (LWA)
1 YD406
MAERSK AIR (MRS)
1 YA203–YA211 YA221
MALEV HUNGARIAN AIRLINES (HGA)
1Y A 3 7 1
MANDARIN AIRLINES (MDN)
1 YC587–YC588

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
MIAMI AIR (MIB)
1 YC146 YC904–YC905
MID EAST JET (SKL)
1 YG013–YG014
MONGOLIAN AIRLINES MIAT (MNG)
1Y J 4 7 6
MULTIFLIGHT (MFL)
1 YD404
NATIONAL (NJI)
1Y G 0 3 2
NATIONAL AIR SERVICES (NAR)
1 YG086–YG087
NEOS (NEO)
1 YJ002 YJ631–YJ632
NEWS AMERICA INCORPORATED (NWS)
1Y G 0 2 0
NOVAIR (NOO)
1 YC705
OMAN AIR (OMR)
1 YA366–YA367 YB551 YC171
OMNIFLYS (OML)
1Y G 0 7 7
PEGASUS AIRLINES (PGS)
1 YC391–YC392 YC406 YC410 YC412
YC414–YC415 YC572–YC573 YD025 YD391
PICTON II (UNU)
1Y G 0 0 6
POLYNESIAN AIRLINES (PLY)
1 YC147
PRIVATAIR (PTS)
1 YG018–YG019 YG064
QANTAS (QAN)
1 YC878–YC892
REPUBLIC OF CHINA AIR FORCE (CAF)
1 YC396

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
ROYAL AIR MAROC (RAM)
1 YA831–YA835 YC301–YC304
ROYAL JORDANIAN AIR FORCE (RYJ)
1Y G 0 3 9
ROYAL MALAYSIA AIR FORCE (MAF)
1Y G 0 6 1
ROYAL SAUDI AIR FORCE (RSA)
1 YD403 YG080
RYANAIR (RYR)
1 YC471–YC499 YJ801–YJ804
SAMSUNG TECHWIN CO. (SST)
1Y G 0 7 9
SAS (SAS)
1 YB001–YB006 YD041 YD046–YD055 YD081–YD084
YE001–YE020 YE051 YE101–YE109
SAS INSTITUTE INC. (SJS)
1Y G 0 4 1
SAUDI OGER (SAO)
1 YD401 YG073
SHANGHAI AIRLINES (SHA)
1 YA272 YA312–YA314 YA891–YA892 YC166–YC169
YJ871
SHARE JET (SJL)
1Y G 0 8 2
SHENZHEN AIRLINES (SHZ)
1 YA613 YA626 YA686–YA687 YA721–YA722
YA801–YA803 YA809 YC153–YC154 YC411
YC413
SIGAIR (SIG)
1Y G 0 3 4
SILVER ARROWS (SIQ)
1Y G 0 6 2
SKY AIRLINES (SYC)
1Y C 7 3 0
SOUTH AFRICAN AIRFORCE (SFF)
1Y G 0 7 6

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
SOUTH AFRICAN AIRWAYS (SAA)
1 YC708–YC715 YC720–YC725 YD023–YD024 YD481–YD483
SOUTHERN AIRCRAFT SERVICES (HUZ)
1Y G 0 0 9
SOUTHWEST AIRLINES (SWA)
1 YA001–YA099 YA101–YA128 YA271 YA301
STERLING EUROPEAN AIRLINES (STR)
1 YC101–YC104 YC751–YC752
SUN COUNTRY AIRLINES (SCA)
1 YC121 YC152 YC155–YC156
SUNEXPRESS (SNS)
1 YC453 YC455 YC702 YC706
YJ477–YJ479
SWIFLITE AIRCRAFT CORPORATION (OSF)
1Y G 0 7 8
TAROM - ROMANIAN AIR TRANSPORT (TRM)
1 YB161–YB162
TBN AVIATION AVV (TBE)
1Y G 0 2 9
TRACINDA CORP. (TRD)
1Y G 0 0 4
TRANSAERO AIRLINES (TRX)
1 YA251–YA252
TRANSAVIA AIRLINES (TAV)
1 YB521 YC071–YC082 YC091–YC094
TRAVEL SERVIS (TSF)
1 YC408 YC454 YC459 YD203
YJ474
TUI AIRLINES BELGIUM (TLB)
1 YD217
TUNISAIR (TUN)
1 YE151–YE157 YG030
TURKISH AIRLINES (THY)
1 YC501–YC526
TUTOR-SALIBA CORPORATION (TTS)
1Y G 0 7 0

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
UNITED STATES NAVY (USN)
1 YG501–YG506
US AIR FORCE (USF)
1 YG074 YG081 YG084 YG088
VARIG AIRLINES (VAR)
1 YA322–YA323 YA573 YC728–YC729
VIRGIN BLUE AIRLINES (VOZ)
1 YA336–YA345 YA544 YA546 YA649
YA658–YA659 YA685 YA688–YA691 YC421–YC422
YC921–YC922 YD201–YD202 YD251–YD254
WESTJET (WJI)
1 YB301–YB310 YB601–YB605
XIAMEN AIRLINES (XIA)
1 YA701–YA708
YEMENIA (YEM)
1 YC176–YC178
YONA AVIATION II, LLC (VRH)
1Y G 0 4 3
IDENTIFICATION BY VARIABLE NUMBER
Variable Group
YA001–YA099 1
YA101–YA128 1
YA201–YA211 1
YA221 1
YA231–YA242 1
YA251–YA256 1
YA271–YA272 1
YA291 1
YA301–YA302 1
YA311–YA314 1
YA321–YA323 1
YA336–YA345 1
YA351 1
YA356–YA357 1
YA366–YA367 1
YA371 1
YA501–YA536 1
YA541–YA552 1

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
YA571–YA578 1
YA601–YA615 1
YA621–YA622 1
YA626–YA629 1
YA635–YA636 1
YA641 1
YA645–YA650 1
YA656–YA659 1
YA671–YA672 1
YA681–YA691 1
YA701–YA708 1
YA721–YA722 1
YA731–YA734 1
YA751–YA756 1
YA801–YA803 1
YA809 1
YA811–YA814 1
YA831–YA835 1
YA841–YA858 1
YA881–YA882 1
YA891–YA892 1
YA961–YA970 1
YB001–YB006 1
YB101–YB120 1
YB151–YB153 1
YB161–YB162 1
YB171–YB172 1
YB181–YB183 1
YB201–YB207 1
YB271 1
YB276 1
YB301–YB310 1
YB501–YB502 1
YB521 1
YB551 1
YB561–YB566 1
YB601–YB605 1
YC001–YC030 1
YC051–YC082 1
Variable Group

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
YC091–YC094 1
YC101–YC104 1
YC111–YC113 1
YC121 1
YC126–YC127 1
YC136–YC141 1
YC146–YC147 1
YC151–YC156 1
YC166–YC169 1
YC171 1
YC176–YC178 1
YC186 1
YC301–YC304 1
YC321–YC383 1
YC391–YC392 1
YC396 1
YC401–YC417 1
YC421–YC422 1
YC426–YC428 1
YC436–YC437 1
YC441–YC448 1
YC451–YC455 1
YC459 1
YC461–YC467 1
YC471–YC499 1
YC501–YC526 1
YC571–YC583 1
YC587–YC589 1
YC591–YC593 1
YC601–YC655 1
YC681–YC696 1
YC701–YC715 1
YC720–YC725 1
YC727–YC741 1
YC751–YC752 1
YC761–YC770 1
YC781–YC793 1
YC801–YC892 1
YC901–YC907 1
Variable Group

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
YC921–YC922 1
YC931–YC932 1
YC941–YC951 1
YC971–YC978 1
YC981–YC983 1
YD001–YD006 1
YD021–YD025 1
YD041–YD055 1
YD081–YD084 1
YD101–YD107 1
YD121–YD126 1
YD151–YD155 1
YD171–YD172 1
YD201–YD203 1
YD206–YD209 1
YD216–YD217 1
YD251–YD254 1
YD256–YD257 1
YD301–YD330 1
YD391 1
YD401–YD410 1
YD481–YD483 1
YD501–YD507 1
YD531–YD534 1
YD541–YD547 1
YD601–YD612 1
YE001–YE020 1
YE051 1
YE101–YE109 1
YE151–YE157 1
YE171–YE172 1
YE201–YE204 1
YE301–YE305 1
YG001–YG044 1
YG061–YG064 1
YG066–YG089 1
YG201 1
YG501–YG506 1
YG601–YG602 1
Variable Group

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
2. Spares Affected
Add marks on the aft surface of the hanger fitting and the center link assembly with “L”, “R” and
“AFT” to identify the correct position for installation. Change the part numbers on the hanger
fitting and the center link assembly. Refer to paragraph 3.B., Work Instructions, Part 2.
YJ001–YJ002 1
YJ471–YJ479 1
YJ501–YJ517 1
YJ631–YJ632 1
YJ671–YJ676 1
YJ801–YJ804 1
YJ871 1
Variable Group

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
B. Concurrent Requirements
None.
C. Reason
Part 1 of this service bulletin was initially prepared to give instructions for operators to do a one-time
inspection of all airplanes that have had an engine change since the airplane was delivered. It is
necessary to do the inspection on all subsequent engine changes unless Part 2 marked engine
mounts are installed.
In September 2003, an operator told Boeing that an airplane was found with a center link installed
incorrectly on an aft engine mount. The operator also told Boeing that the airplane had not had an
engine change since the new airplane was received from Boeing. As a result, it is necessary for
airplanes that have not had an engine changed since the new airplane was received from Boeing to
do the Part 1 inspection on each of the aft engine mounts.
In October 2001, one operator told Boeing it was necessary to get clarification of manuals related to
engine mount assembly and installation. After the initial help from Boeing, the operator reported that
the aft engine mount center link assembly, P/N 310A2034-3, could have been reversed during
overhaul assembly and subsequently installed on airplanes. The operator inspected all airplanes that
had engine installations since the airplanes were delivered. Six reversed center links were found,
which were immediately corrected. No damage was reported after visual inspection of the aft mount
and local engine attachment was completed.
The operator found that no anomalies were reported during the aft engine mount installations or during
the engine installations. It was found that some increase in force was necessary to install the pawl pins
that attach the aft engine mount to the engine.
In December 2001, a second operator told Boeing about problems they had when they tried to close
the thrust reversers after engine replacement. Visual inspection showed gap differences between the
thrust reverser aft cowl and the primary exhaust sleeve on the two sides of the engine. The engine
was lowered and the subsequent inspection found a reversed center link assembly, part number
310A2034-7. After the center link was removed and installed correctly, the engine installation was
completed satisfactorily.
Although the center link has an apparent symmetrical shape, there is a 0.2175 inch difference in the
distances between the center bearing and each side bearing. Also, the two spherical bearings
installed at each end are not the same bore diameter. The center link can be installed 180 degrees
from the correct location (reversed) and still be attached to the engine with the pawl pins in the correct
location. More force can be necessary to install the pins.
The reversed center link condition changes the structural loading of the aft engine mount interface with
the engine. If not corrected, failure of the aft engine mount can occur. Also, the reversed center link
installation causes a 0.174 inch displacement of the engine turbine rear frame to the right. The thrust
reverser cowls are not easily closed if this condition exist.
Part 2 gives instructions to install the permanent marks on the aft engine mount, which, if installed,
releases operators from the inspection requirements given in Part 1 of this service bulletin. The
permanent marks identify the correct installation position of the hanger fitting assembly and the center
link assembly of the aft engine mount.
Boeing Service Related Problem (SRP) 737-SRP-71-0035 is related to this service bulletin.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
Revision 1: This revision was sent to inform operators of the changes shown below:
The information given in the ACTION section in the Service Bulletin Summary has changed.
The information given in Paragraph 1.D., Description section of the Service Bulletin has changed.
Information has been added and the compliance time has changed in the Service Bulletin Summary
and in Paragraph 2.E. of the Service bulletin.
Paragraph 3.B.2., Work Instructions, a NOTE has been added to inform operators that the best view
of center link can be found from the left side of the engine.
More information has been added to the Steps in Figure 2.
More information has been added to the Steps in Figure 4, a new STEP 3 has been added and the
initial STEP 7 has been deleted. The initial Steps 3 through 6 have been re-numbered.
Revision 2: This revision was sent to add airplanes to the effectivity and to change the inspection given
in the initial release and in Revision 1 of this service bulletin. The inspection, identified as Part 1, is
revised from a one-time inspection to an inspection of all subsequent engine installations. Part 2 is
added to give instructions to install permanent marks on the hanger fitting and the center link. The
permanent marks identify the correct position for installation of the hanger fitting and the center link of
the aft mount of the two engines. It is not necessary to do the Part 1 inspection after marked engine
mounts are installed.
The Spares Affected information given in Paragraph 1.A.2., is changed.
Figures 5, 6 and 7 are added to give the instructions to add the marks and change the part numbers
on the hanger fitting and the center link.
FAA Airworthiness Directive (AD) information has also been added.
Revision 3: This revision is sent to tell operators that for the airplanes that have not had an engine
change since the new airplane was received from Boeing, it is possible that some center links were
incorrectly installed in an aft engine mount before the airplane was delivered. Before this revision,
inspection of the aft engine mounts was necessary only for the airplanes that had an engine change
after the new airplane was received from Boeing. With the release of Revision 3 of this service
bulletin, the Part 1 Inspection is applicable to all airplanes given in the effectivity of this service bulletin.
1. On Summary section, Background, paragraph 1.C., Reason and paragraph 1.D., Description,
more information has been added to include the airplanes that have not had an engine change
since the new airplane was received from Boeing.
2. On Summary section, Background, paragraph 1.C., Reason and paragraph 1.J., References, a
new paragraph has been added to show the Boeing Service Related Problem information that is
related to this service bulletin.
3. On Summary section and paragraph 1.E., Compliance information, the paragraphs about Part 1
have been changed to include airplanes that have not had an engine change since the new
airplane was received from Boeing. The paragraphs about Part 2 have been changed to give
more information. All engine installed after 90 days has been changed to during all subsequent
engine changes done after 90 days.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
4. On paragraph 1.A., Planning Information, Effectivity, a group condition table has been added.
5. On paragraph 2.B., Industry Support Information, a warranty statement has been added for
airplanes that have not had an engine change since the new airplane was received from Boeing.
6. On paragraph 2.C.3., Parts Modified and Reidentified table and Figure 5 work instruction table,
Step 2, the part numbers for the hanger fitting 310A2031-23 and the hanger fitting assembly
310A2031-24 have been added.
7. On paragraph 3.B.,Part 1,2., the work instruction step has been changed to delete information
about airplanes that have had an engine change after the airplane was delivered and during
subsequent engine installations. The changed Step 2 make the step applicable to all airplanes
and the same compliance information is already shown in the Compliance paragraphs.
8. On paragraph 3.B.,Part 1,3.e. and Part 2,1., the work instruction steps have been added for
airplanes if do or not do the Part 1 and Part 2 Work Instructions at the same time.
9. On paragraph 3.B.,Part 1,4., the work instruction step has been added for airplanes that have
found the aft engine mounts correctly installed.
10. On paragraph 3.B.,Part 2,4., the work instruction step has been added to close access. The note
on the left, right and aft markings has been changed to a Caution note.
11. Figures 1 and 3 have been changed to show the left side view to agree with the note that said
the best view is from the left side. The view was shown from the right side of the aft engine
mount.
12. Figures 2 and 4 have been changed to delete the assembly and installation steps Steps 9 through
12. The same assembly and installation steps have been moved to the new Figures 8 and 9 for
airplanes that possibly do Part 1 Correction and Part 2 part mark work instructions at the same
time.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
D. Description
Part 1, open the engine thrust reversers and get access to the aft engine mount. Do an inspection of
the aft engine mount to make sure that the center link assembly is correctly installed. If the center link
assembly is incorrectly installed, correct the installation and report this to Boeing. It is necessary to do
the inspection on all subsequent engine changes unless the mount that is installed is marked as given
in Part 2 of this service bulletin.
Revision 1: No more work is necessary on airplanes examined as given in the initial release of this
service bulletin.
Revision 2: More work is necessary on airplanes that had inspections done as specified in Revision 1
of this service bulletin. It is necessary to do the Part 1 inspection unless the center link and hanger
fitting were marked as specified in the Part 2 part mark procedure. Part 2, get access and remove the
aft engine mount. Mark the aft surface of the hanger fitting with “L”, “R”, and “AFT” to identify the
correct location for installation. Mark the aft surface of the center link with “L”, “R” and “AFT” to identify
the correct location for installation. Install the aft engine mount.
Revision 3: More work is necessary for airplanes that have not had an engine change since the new
airplane was received from Boeing, do the Part 1 Inspection procedures unless the Part 1 Inspection
or the Part 2 Part Mark procedures have been done.
No more work is necessary on airplanes that have had an engine change since the new airplane was
received from Boeing, have done the Part 1 Inspection and Part 2 Part Marks procedures.
No airplanes have been added by Revision 3 of this service bulletin. The Revision 2 of this service
bulletin included the airplanes effectivity that could be affected by this service bulletin.
E. Compliance
Federal Aviation Administration (FAA) Airworthiness Directive AD 2003-03-01, Amendment
39-13025, is related to this service bulletin.
Part 1, For airplanes that have had an engine change since the new airplane was received from
Boeing, in 90 days or less from the initial release of SB 737-71A1462, Boeing recommends that
operators do a one-time inspection of the aft engine mount and make sure of the correct installation
of the center link assembly unless the mount is marked as given in the Part 2 of this service bulletin.
If a reversed center link is found, the condition must be corrected before the next flight. If only one
engine on an airplane has been replaced, it is only necessary to do an inspection of that engine.
Part 1: For airplanes that have not had an engine change since the new airplane was received from
Boeing, in 90 days or less from the Revision 3 release of SB 737-71A1462, Boeing recommends that
operators do a one-time inspection of the aft engine mount to make sure of the correct installation of
the center link assembly. If a reversed center link is found, the incorrect condition must be corrected
before the next flight. No more new inspection is necessary if the aft engine mounts were inspected
as shown in the initial, Revision 1 or Revision 2 of this service bulletin.
Part 1: For all subsequent engine changes on all airplanes, Boeing recommends operators do the Part
1 Inspection on each aft engine mount during each subsequent engine change until the marked aft
engine mount is installed.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
Part 2: For all airplanes that have had or have not had an engine change, Boeing recommends that
operators do Part 2 part mark procedures if the engine mount is removed by the Part 1 Work
Instructions, or during a subsequent usual engine maintenance task when the engine removal is
necessary.
Part 2: Boeing recommends that during the subsequent engine changes done after 90 days from the
release of SB 737-71A1462, Revision 2, install permanently marked aft engine mounts. All engine
changes done in 90 days or less from the release of SB 737-71A1462, Revision 2, that do not have
permanently marked aft engine mounts, must have an inspection done as given in the Part 1
Inspection.
F. Approval
This service bulletin was examined by the Federal Aviation Administration (FAA). The changes
specified in this service bulletin comply with the applicable Federal Aviation Regulations (14 CFR Part
25) and Joint Aviation Requirements (JAR-25) and are FAA/JAA approved. This service bulletin and
FAA/JAA approval were based on the airplane in it's original Boeing delivery configuration or as
modified by other FAA/JAA approved Boeing changes.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected
by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency
approval before incorporating this service bulletin.
Note: Joint Airworthiness Requirements (JAR) compliance status may be found in the Service Bulletin
Index, Part 1.
This service bulletin has been approved by the FAA. In addition, the Manager of the FAA Seattle
Aircraft Certification Office approves the action (i.e. inspection or modification) defined in this service
bulletin as an alternative method of compliance to the requirements of paragraphs (b) and (c) of
AD 2003-03-01. All provisions of AD 2003-03-01 that are not specifically referenced in the above
remain fully applicable and must be complied with.
The FAA has examined the marking, part marking and reinstallation specified in Part 2 of the work
Instructions of this service bulletin 737-71A1462. The FAA has approved the marking, partmarking
and reinstallation as an alternative method of compliance to the inspections required by
AD 2003-03-01 paragraph (f) provided future engine installations maintain all of the part marking
requirements required by Part 2 of the Work Instructions of this service bulletin.

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G. Manpower
PART 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY INSTALLATION INITIAL
INSPECTION
Task
Number of
Persons Task-Hours Elapsed Hours
Open Thrust Reversers 2 1.5 0.75
Inspect Center Link Assembly 1 0.50 0.50
Close Thrust Reversers 2 1.5 0.75
TOTAL FOR INITIAL INSPECTION ON EACH ENGINE 3.5 2.0
PART 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY INSTALLATION CORRECTION
Task
Number of
Persons Task-Hours Elapsed Hours
Remove Engine Cowl Panels 2 1.5 0.75
Change Aft Engine Mount:
— Remove Engine
— Remove and Inspect Aft Engine
Mount, Center and Right Link
Assemblies
— Install Aft Engine Mount, Center
and Right Link Assemblies
— Install Engine
43 1 . 0 7 . 5
Install Engine Cowl Panels 2 3.0 1.5
Do Thrust Reversers and Engine
Test
23 . 0 1 . 5
TOTAL FOR INSTALLATION CORRECTION ON EACH
ENGINE
37.0 10.5
TOTAL FOR CONCURRENT INITIAL INSPECTION AND
INSTALLATION CORRECTION ON EACH ENGINE
40.5 12.5
PART 2 : AFT ENGINE MOUNT, HANGER FITTING AND CENTER LINK ASSEMBLY, APPLY
IDENTIFICATION MARKS
Task
Number of
Persons Task-Hours Elapsed Hours
Mark Center Link Assembly and
Hangar Fitting
11 . 5 1 . 5
TOTAL FOR EACH ENGINE (a) 1.5 1.5
(a) Does not include engine mount removal and installation times. See Part 1 for the engine,
engine mount removal and installation times.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
H. Weight and Balance Changes
None.
I. Electrical Load Data
Not applicable.
J. References
1. Existing Data:
a. 737 Maintenance Manual (AMM) Subject 71-00-02, 71-11-02, 71-21-03, 78-31-00
b. 737 Structural Repair Manual (SRM) Subject 51-40-04
c. Component Maintenance Manual (CMM) 71-21-37
d. Boeing Document D6-19567, Service Bulletin Index
e. FAA Airworthiness Directive AD 2003-03-01, Amendment 39-13025
f. Boeing Service Related Problem (SRP) 737-SRP-71-0035
2. Data supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
These drawings were used to prepare this service bulletin. These drawings are not necessary to
make the specified changes, and are not supplied with this service bulletin. These drawings may
not be applicable to all airplane configurations or operators.
4. Process Data:
Boeing Process specifications referred to on the drawings are not given in this service bulletin
since these procedures are frequently used as standard shop practices.
Drawing Number Title
310A2030 AFT ENGINE MOUNT INSTL, CFM56-7
310A2031 HANGER ASSY - AFT ENGINE MOUNT, CFM56-7
310A2034 LINK ASSY - CENTER, AFT ENGINE MOUNT, CFM56-7

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
K. Publications Affected
L. Interchangeability and Intermixability of Parts
Accomplishment of this service bulletin does not affect interchangeability or intermix ability of parts.
Publication Chapter-Section
737 Maintenance Manual 71-21
737 Power Plant Build-Up Manual 71-00
737 Illustrated Parts Catalog 71-21
Component Maintenance Manual 71-21

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
2. MATERIAL INFORMATION
A. Material - Price and Availability
None.
B. Industry Support Information
For operators of airplanes that have not had an engine change since the new airplane was received
from Boeing:
Boeing warranty remedies are available for 737 airplanes in warranty as of October 9, 2003. For
inspection man-hour reimbursement for airplanes in warranty as of that date, send a warranty claim
to Boeing Commercial Airplanes Group - Warranties. If the condition described in this service bulletin
is found during the inspection for airplanes in warranty as of that date and additional man-hours are
required, send a warranty claim to Boeing Commercial Airplanes Group - Warranties.
For operators of airplanes that have had an engine change since the new airplane was received from
Boeing:
Boeing warranty remedies are not available for the inspection given in this service bulletin.
C. Parts Necessary For Each Airplane
1. Kits/Parts:
None.
2. Parts and Materials Supplied by the Operator:
None.
3. Parts Modified and Reidentified:
The parts shown below are changed as shown in this service bulletin. The quantity (QTY) is the
number of parts changed on each airplane. Components or subassembly parts are indented. The
quantity of the indented part is the number of parts used on the next higher assembly.
Existing Part
Number QTY Name New Part Number Notes
310A2031-22 1 Hanger Fitting Assembly 310A2031-24 (a) (b) (c)
310A2031-23 1 Hanger Fitting 310A2031-25 (a) (b) (c)
310A2034-3 1 Center Link Assembly 310A2034-14 (a) (b) (c)
310A2034-7 1 Center Link Assembly 310A2034-13 (a) (b) (c)
310A2034-8 1 Center Link Assembly 310A2034-14 (a) (b) (c)
(a) Make the change given in this service bulletin.
(b) This is the part number after the change given in this service bulletin.
(c) This part is used in production.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
4. Parts Removed and Not Replaced:
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But,
maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be
necessary. Examine operator tool supply to make sure all necessary tools are available.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
3. ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
CAUTION: KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL
PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED
MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES
CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE
SPARKS OR OTHER ELECTRICAL DAMAGE.
Note:
1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
2. The work instructions are divided into two parts. Part 1 gives instructions to do an
inspection and if necessary, correct the installation of the aft engine mounts. Part 2 gives
instructions to mark the hanger fitting and the center link assembly of the aft mounts of the
two engines.
3. Obey all of the warnings and cautions given in the specified manual sections.
4. Unless shown differently, these dimensions and tolerances are used:
— Linear dimensions are in inches
— Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus or
minus 0.03 inch.
— Angular tolerance is plus or minus 2 degrees
— Torque limits to tighten nuts and bolts are given in 737 Structural Repair Manual
(SRM) 51-40-04.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
B. WORK INSTRUCTIONS
PART 1: Inspection and correction of aft engine mounts
1. Open the thrust reversers. Refer to 737 AMM 78-31-00/201.
2. Do a detailed inspection of the aft engine mount on each engine position. Make sure that the
center link assembly is correctly installed. See Figure 1 for Center Link Assembly, part number
310A2034-3 (without pockets) and Figure 3 for Center Link Assembly, part numbers
310A2034-7 or -8 (with pockets).
Note:
1. Airplanes can have two different types of center links installed. Refer to Figure 1 or
Figure 3.
2. The best view of the center link assembly is from left side of the engine.
3. If an incorrectly installed center link assembly is found, remove and install it correctly and do the
items below before the next flight. See Figure 2 for Center Link Assembly, part number
310A2034-3 (without pockets) or Figure 4 for Center Link Assembly, part numbers 310A2034-7
or -8 (with pockets).
a. Do a detailed inspection on the mount lugs of the engine turbine rear frame.
Do an inspection of the engine mounting lugs and the adjacent engine turbine rear frame
area for cracks, yielding, buckling, and wear damage. Contact CFMI for more instructions
if damaged hardware is found.
b. Do a detailed inspection of the aft engine mount hardware.
(1) Do an inspection of the parts specified below for cracks, yielding, buckling and wear
damage. See Figure 2 or Figure 4.
(a) Center link Assembly 310A2034-( ).
(b) Right link Assembly 310A2035-( ).
(c) Aft mount hanger assembly 310A2031-( ), at the interfaces with the center link and
right link.
(d) 310A2037-( ) link pins that are removed during disassembly.
(2) If any damage is found, contact the Boeing Field Service Representative for more
instructions.
c. Record the installed engine information on the form that is supplied in Appendix A of this
service bulletin. See Appendix A.
d. Give the completed Appendix A form to your Boeing Field Service Representative and your
CFMI Representative.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
e. Do steps (1) or (2) shown below.
(1) Do the Part 2 work instructions to add the permanent part marks on the center link
assembly and the hanger fitting before the engine installation. See the Part 2 Work
Instructions.
(2) If the Part 2 Work Instructions is not done, do these steps shown below.
Note: The Part 2 part mark procedures can be done at the same time during a
subsequent usual engine maintenance task that makes the engine removal
necessary.
(a) Assemble and install the aft engine mounts and install the engines. Refer to
Figure 8 for Center Link Assembly, part number 310A2034-3 (without pockets) or
Figure 9 for Center Link Assembly, part numbers 310A2034-7 or -8 (with pockets).
(b) Close the thrust reversers. Refer to 737 AMM 78-31-00/201.
(c) Install the fan cowl panels. Refer to 737 AMM 71-11-02/401.
(d) Do the operational test of the thrust reversers. Refer to 737 AMM 78-31-00/501.
(e) Do the tests of the installed engine. Refer to 737 AMM 71-00-02/401.
(f) Put the airplane back to a serviceable condition.
4. If a correctly installed center link assembly is found, do these steps shown below.
a. Close the thrust reversers. Refer to 737 AMM 78-31-00/201.
b. Do the operational test of the thrust reversers. Refer to 737 AMM 78-31-00/501.
c. Put the airplane back to a serviceable condition.

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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
PART 2: Mark the hanger fitting and center link
1. If the Part 2 is not done at the same time with Part 1 or with other usual engine maintenance tasks
that make the engine removal necessary, do these steps below at each engine position.
a. Open the thrust reversers. Refer to 737 AMM 78-31-00/201.
b. Remove and keep the fan cowl panels. Refer to 737 AMM 71-11-02/401.
c. Remove and keep the engine. Refer to 737 AMM 71-00-02/401.
d. Remove and disassemble the aft engine mount. Refer to 737 AMM 71-00-02/401,
737 AMM 71-21-03 and 737 CMM 71-21-37.
2. Add marks on the aft face of the hanger fitting and change the part number. See Figure 5.
3. Add marks on the aft face of the center link assembly and change the part number. See Figure
6 or Figure 7.
Note: Airplanes can have two different types of center links installed.
4. Do these steps below to install the aft engine mounts, engines and close access.
CAUTION: MAKE SURE THAT THE “L”, “R”, AND “AFT” MARKINGS ARE ON THE NEAR
SIDE WHEN SEE FROM THE AFT SIDE OF THE ENGINE MOUNT. MAKE SURE
THAT THE MARKINGS ON THE CENTER LINK ASSEMBLY AGREE WITH THE
“L”, “R”, AND “AFT” MARKINGS THAT ARE ON THE HANGER FITTING WHEN
THE CENTER LINK ASSEMBLY IS INSTALLED ON THE HANGER FITTING.
a. Assemble and install the aft engine mounts and install the engines. Refer to Figure 8 for
Center Link Assembly, part number 310A2034-3 (without pockets) or Figure 9 for Center
Link Assembly, part numbers 310A2034-7 or -8 (with pockets).
b. Close the thrust reversers. Refer to 737 AMM 78-31-00/201.
c. Install the kept fan cowl panels. Refer to 737 AMM 71-11-02/401.
d. Do the tests of the installed engine. Refer to 737 AMM 71-00-02/401.
e. Do the operational test of the thrust reversers. Refer to 737 AMM 78-31-00/501.
5. Put the airplane back to a serviceable condition.

### Page 39

FIGURE 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) INSTALLATION
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) INSTALLATION
INSPECTION
ASSEMBLY
CENTER LINK
AFT ENGINE MOUNT
LEFT THRUST
LINK
FWD
SEE B
A
ASEE
V88902
(SHEET 1 OF 2)

### Page 40

FIGURE 1: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) INSTALLATION
INSPECTION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Inspect Center Link
Assembly
310A2034-3 1 Make sure that the loader
relief slots are seen on the
aft face of link.Center Bearing S302T001-822 1
Note:
1. The best view of the center link assembly is from the left side of the engine.
2. The loader relief slots are located 180 degrees apart and are used to install the
spherical bearing in the bearing race.
RELIEF SLOTS
LOADER
A-A
FWD 1
B
V88891
(SHEET 2 OF 2)

### Page 41

FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
INSPECTION
CENTER LINK
ASSEMBLY
AFT ENGINE MOUNT
FRAME LUGS
TURBINE REAR
LEFT THRUST LINK
FWD
ASEE
A
1
SEE B
V88901
(SHEET 1 OF 4)

### Page 42

FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
LINK PINS
TURBINE
REAR FRAME
FWD
B
3
8
2 CSEE
2
V88889
(SHEET 2 OF 4)

### Page 43

FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
LINK PIN
LINK PIN
ASSEMBLY
CENTER LINK
ASSEMBLY
RIGHT LINK
FWD
6 7
6 7
4 5
C
4 5
8
N45757
(SHEET 3 OF 4)

### Page 44

FIGURE 2: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 44 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Remove/
Lower
Engine - 1 Refer to 737 AMM
71-00-02/401.
2 Remove/
Keep
Aft Engine mount 310A2030-6 or -11 1 Refer to 737 AMM
71-21-03/401.
Link Pins 310A2037-( ) 4
3 Inspect Link Pins 310A2037-( ) 4 Check for cracks, yielding,
buckling and wear damage.
4 Remove/
Keep
Center Link
Assembly
310A2034-3 1 Refer to 737 CMM
71-21-37/301.
Link Pin 310A2037-( ) 1
5 Inspect Center Link
Assembly
310A2034-3 1 Check for cracks, yielding,
buckling and wear damage.
Link Pin 310A2037-( ) 1
6 Remove/
Keep
Right Link
Assembly
310A2035-5, -7 or -8 1 Refer to 737 CMM
71-21-37/301.
Link Pin 310A2037-( ) 1
7 Inspect Right Link
Assembly
310A2035-5, -7 or -8 1 Check for cracks, yielding,
buckling and wear damage.
Link Pin 310A2037-( ) 1
8 Inspect Aft Engine Mount 310A2030-6 or -11 1 Check for cracks, yielding,
buckling and wear damage.
Engine Rear
Frame
--
Note: Do a detailed inspection of the aft engine mount and engine turbine rear frame
interface for damage before the center link and right link assemblies are installed.
(SHEET 4 OF 4)

### Page 45

FIGURE 3: AFT ENGINE MOUNT, CENTER LINK (WITH POCKETS) INSTALLATION INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 3: AFT ENGINE MOUNT, CENTER LINK (WITH POCKETS) INSTALLATION INSPECTION
ASSEMBLY
CENTER LINK
AFT ENGINE MOUNT
LEFT THRUST
LINK
FWD
SEE B
A
ASEE
V88902
(SHEET 1 OF 2)

### Page 46

FIGURE 3: AFT ENGINE MOUNT, CENTER LINK (WITH POCKETS) INSTALLATION INSPECTION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Inspect Center Link
Assembly
310A2034-7 or -8 1 Make sure that the loader
relief slots are at the aft
face of the center link
assembly.Center Bearing S302T001-702 or -822 1
Note:
1. The best view of the center link is from the left side of the engine.
2. The center link assembly 310A2034-7 has the center bearing part numbers
S302T001-702 or S302T001-822 installed.
3. The center link assembly 310A2034-8 has the center bearing part number
S302T001-822 installed.
2 Inspect Center Link
Assembly
310A2034-7 or -8 1 Make sure that the larger
of the two pockets is on
the left side.
A-A
FWD
POCKET
SMALL
RELIEF SLOTS
LOADER
LARGE
POCKET
1
2
B
V86799
(SHEET 2 OF 2)

### Page 47

FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
INSPECTION
LEFT THRUST LINK
TURBINE REAR
FRAME LUGS
AFT ENGINE MOUNT
ASSEMBLY
CENTER LINK
FWD
SEE B
1
A
ASEE
V86781
(SHEET 1 OF 4)

### Page 48

FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
REAR FRAME
TURBINE
LINK PINS
FWD
2 3
CSEE2
8
B
V86800
(SHEET 2 OF 4)

### Page 49

FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
LINK PIN
LINK PIN
ASSEMBLY
CENTER LINK
ASSEMBLY
RIGHT LINK
FWD
6 7
6 7
4 5
4 5
C
8
N45582
(SHEET 3 OF 4)

### Page 50

FIGURE 4: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) REMOVAL AND
INSPECTION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 50 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Remove/
Lower
Engine - 1 Refer to 737 AMM
71-00-02/401.
2 Remove/
Keep
Aft Engine mount 310A2030-11 or -12 1 Refer to 737 AMM
71-21-03/401.
Link Pins 310A2037-( ) 4
3 Inspect Link Pins 310A2037-( ) 4 Check for cracks, yielding,
buckling and wear damage.
4 Remove/
Keep
Center Link
Assembly
310A2034-7 or -8 1 Refer to 737 CMM
71-21-37/301.
Link Pin 310A2037-( ) 1
5 Inspect Center Link
Assembly
310A2034-7 or -8 1 Check for cracks, yielding,
buckling and wear damage.
Link Pin 310A2037-( ) 1
6 Remove/
Keep
Right Link
Assembly
310A2035-5, -7 or -8 1 Refer to 737 CMM
71-21-37/301.
Link Pin 310A2037-( ) 1
7 Inspect Right Link
Assembly
310A2035-5, -7 or -8 1 Check for cracks, yielding,
buckling and wear damage.
Link Pin 310A2037-( ) 1
8 Inspect Aft Engine Mount 310A2030-11 or -12 1 Check for cracks, yielding,
buckling and wear damage.
Engine Turbine
Rear Frame
--
Note: Do a detailed inspection of the aft engine mount and engine turbine rear frame
interface for damage before the center link and right link assemblies are installed.
(SHEET 4 OF 4)

### Page 51

FIGURE 5: HANGER FITTING, ADD IDENTIFICATION MARKS
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 5: HANGER FITTING, ADD IDENTIFICATION MARKS
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine mount.
STEP TASK NAME PART NUMBER QTY NOTE
1 Mark Hanger
Fitting
310A2031-23 1 Mark aft face with “L”, “R” and “AFT”.
Use the vibro-engraving method.
Refer to BSOPM 20-50-10
Note:
1. The left “L” and right “R” letters height are 0.375 inch high.
2. The “AFT” letters height: are 1.0 inch high.
2 Identify Hanger
Fitting
Assembly
310A2031-24 1 Change the part number from the
310A2031-22 to 310A2031-24.
Recommend to use a rubber stamp
method and the part number location is
optional. Refer to BSOPM 20-50-10.
Hanger
Fitting
310A2031-25 1 Change the part number from the
310A2031-23 to 310A2031-25. Use
the vibro-engraving method. Refer to
BSOPM 20-50-10.
0.85
1.35 (2 PLACES)
1.95
2.45
(2 PLACES)
0.25
0.55
0.85
1.35
HANGER FITTING
2
1
(SHEET 1 OF 1)

### Page 52

FIGURE 6: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS), ADD IDENTIFICA-
TION MARKS
August 29, 2002
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BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 6: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS), ADD
IDENTIFICATION MARKS
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Mark Center Link
Assembly
310A2034-3 1 Mark aft face with “L”, “R” and “AFT”.
Use the vibro-engraving method.
Refer to BSOPM 20-50-10
Note: Make the left “L”, right ”R” and “AFT” letters 0.375 inch high.
2 Identify Center Link
Assembly
310A2034-14 1 Change the part number from
310A2034-3 to 310A2034-14.
Use the vibro-engraving method or
electrochemical etching method.
Refer to BSOPM 20-50-10.
BEARING
DIAMETER
1.00
0.39
0.69
0.05
0.25
0.05
0.25
0.56
0.86
1
WITHOUT POCKETS
CENTER LINK ASSEMBLY
2
0.10 MINIMUM
BEARING
DIAMETER
1.18
0.10 MINIMUM
MINIMUM
0.10
1
W21580
(SHEET 1 OF 1)

### Page 53

FIGURE 7: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS), ADD IDENTIFICATION
MARKS
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 53 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 7: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS), ADD IDENTIFICATION
MARKS
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
1 Mark Center Link
Assembly
310A2034-7 or -8 1 Mark aft face with “L”, “R” and “AFT”. Use
the vibro-engraving method. Refer to
BSOPM 20-50-10
Note: 1. Make sure that the 1.00 inch inside diameter bearing and the larger of the two pockets
located on the left side.
2. Make the right ”R” and “AFT” letters 0.375 inch high.
3. Make the left “L” letter 0.20 inch high.
2 Change Center Link
Assembly
310A2034-13 or -14 1 Change the part number by a vibro-
engraving method or electrochemical
etching method. Refer to BSOPM 20-50-10
Note: 1. Change the part number on either location.
2. Change the part number from 310A2034-7 to 310A2034-13. Change the part
number from 310A2034-8 to 310A2034-14.
BEARING
1.00 DIAMETER
1
WITH POCKETS
CENTER LINK ASSEMBLY
2 0.10 MINIMUM
BEARING
DIAMETER
1.18
0.10 MINIMUM
MINIMUM
0.10
1
SMALL POCKET
LARGE POCKET
0.03 MINIMUM
0.03 MINIMUM
0.03 MINIMUM POCKET RADIUS
MINIMUM FROM
LOCATE 0.05
(SHEET 1 OF 1)

### Page 54

FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
INSTALLATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 54 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
INSTALLATION
LINK PIN
LINK PIN
ASSEMBLY
CENTER LINK
RELIEF SLOTS
LOADER
ASSEMBLY
RIGHT LINK
1.00 BEARING
A-A
A
A
FWD
2
2
1
1
ASEE
385917
AFT ENGINE MOUNT
(SHEET 1 OF 4)

### Page 55

FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
INSTALLATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 55 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
LINK PINS
FWD
A
3
3 BSEE
AFT ENGINE MOUNT
385918
(SHEET 2 OF 4)

### Page 56

FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
INSTALLATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 56 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
CENTER LINK
ASSEMBLY
AFT ENGINE MOUNT
FRAME LUGS
TURBINE REAR
LEFT THRUST LINK
FWD
B
4
SEE C
C
385869
(SHEET 3 OF 4)

### Page 57

FIGURE 8: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITHOUT POCKETS) AND ENGINE
INSTALLATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 57 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below is for each engine.
STEP TASK NAME PART NUMBER QTY NOTE
CAUTION: MAKE SURE THAT THE 1.00 INCH INSIDE DIAMETER BEARING IS LOCATED ON THE
LEFT SIDE AND THE LOADER RELIEF SLOTS ARE LOCATED ON THE AFT FACE OF
THE CENTER LINK WHEN SEE FROM THE AFT SIDE OF THE CENTER LINK
DURING INSTALLATION.
CAUTION: IF THE PARTS ARE MARKED, MAKE SURE THAT THE “L”, “R”, AND “AFT” MARKINGS
ARE ON THE NEAR SIDE WHEN SEE FROM THE AFT SIDE OF THE ENGINE MOUNT.
MAKE SURE THAT THE MARKINGS ON THE CENTER LINK ASSEMBLY AGREE WITH
THE “L”, “R”, AND “AFT” MARKINGS THAT ARE ON THE HANGER FITTING WHEN THE
CENTER LINK ASSEMBLY IS INSTALLED ON THE HANGER FITTING.
1I n s t a l l
(Kept)
Center Link
Assembly
310A2034-3 1 Refer to 737 CMM
71-21-37/701.
Link Pin 310A2037-( ) 1
2I n s t a l l
(Kept)
Right Link
Assembly
310A2035-5, -7 or -8 1 Refer to 737 CMM
71-21-37/701.
Link Pin 310A2037-( ) 1
3I n s t a l l
(Kept)
Aft Engine Mount 310A2030-6 or -11 1 Refer to 737 AMM
71-21-03/401.
Link Pins 310A2037-( ) 4
4I n s t a l l
(Kept)
Engine - 1 Refer to 737 AMM
71-00-02/401.
(SHEET 4 OF 4)

### Page 58

FIGURE 9: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) AND ENGINE INSTAL-
LATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 58 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
FIGURE 9: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) AND ENGINE
INSTALLATION
SMALL POCKET
LINK PIN
LINK PIN
ASSEMBLY
CENTER LINK
RELIEF SLOTS
LOADER
ASSEMBLY
RIGHT LINK
LARGE POCKET
1.00 BEARING
A-A
AFT ENGINE MOUNT
A
A
FWD
2
2
1
1
ASEE
385931
(SHEET 1 OF 4)

### Page 59

FIGURE 9: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) AND ENGINE INSTAL-
LATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 59 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
LINK PINS
AFT ENGINE MOUNT
FWD
3
3
A
BSEE
385934
(SHEET 2 OF 4)

### Page 60

FIGURE 9: AFT ENGINE MOUNT, CENTER LINK ASSEMBLY (WITH POCKETS) AND ENGINE INSTAL-
LATION
August 29, 2002
Revision 3 May 20, 2004 737-71A1462
BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. 60 of 62
BOEING SERVICE BULLETIN 737-71A1462
ALERT ALERT
CENTER LINK
ASSEMBLY
AFT ENGINE MOUNT
FRAME LUGS
TURBINE REAR
LEFT THRUST LINK
FWD
B
4
SEE C
C
385936
(SHEET 3 OF 4)

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