Installation of the Forward Engine Mount Bolts One at a Time [IAE]

TASK 71-21-12-400-010-A
Installation of the Forward Engine Mount Bolts One at a Time

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 400
FIN: 1500KM ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.40 and 0.27 m.daN (35.40 and 23.89 lbf.in )
No specific	Torque wrench: range to between 0.45 and 0.39 m.daN (39.82 and 34.51 lbf.in )
No specific	Torque wrench: range to between 17.99 and 11.99 m.daN (132.67 and 88.42 lbf.ft )
No specific	Torque wrench: range to between 47.45 and 43.39 m.daN (349.93 and 319.99 lbf.ft )
98D71203001000	1	CHEST,TORQUE SET-ENGINE R I

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.V02-147)	lockwire
(Material No.V02-272)	safety cable kit
(Material No.V02-273)	safety cable kit
(Material No.V02-274)	safety cable kit
(Material No.V02-275)	safety cable kit
(Material No.V02-276)	safety cable kit
(Material No.V02-277)	safety cable kit
(Material No.V02-278)	safety cable
(Material No.V02-279)	safety cable kit
(Material No.V02-280)	safety cable ferrule
(Material No.V02-281)	safety cable ferrule
(Material No.V10-078)	anti-seize compound

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 70-23-11-911-013-A	General Torque Tightening Techniques
TASK 70-40-11-911-014-A	Locking Devices General Information
TASK 70-40-11-911-016-A	General Instructions for Uses of Safety Cable
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 71-13-00-410-010-A	Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-30-00-440-012-A	Re-activation of the Thrust Reverser Hydraulic Control Unit (HCU) after Ground Maintenance
TASK 78-32-00-010-010-A	Opening of the Thrust Reverser Halves
TASK 78-32-00-410-010-A	Closing of the Thrust Reverser Halves
Forward Engine Mount Bolts

3. Job Set-up
Subtask 71-21-12-860-051-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.

Subtask 71-21-12-010-062-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Make sure that the fan cowl doors are open (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL, 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL, 448AR.
(2) Make sure that the thrust reverser halves are open (Ref. AMM TASK 78-32-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
451AL, 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL, 462AR.

Subtask 71-21-12-040-056-A ** ON A/C NOT FOR ALL

C. Make sure that the hydraulic control unit is deactivated (Ref. AMM TASK 78-30-00-040-012).

4. Procedure
Subtask 71-21-12-420-052-A ** ON A/C NOT FOR ALL

A. Installation of the Forward Engine Mount bolts

Forward Engine Mount Bolts ** ON A/C NOT FOR ALL

(1) Lubricate the bolts (1) and (16), the washers (2) and (15) and the nuts (3) and (14) with anti-seize compound (Material No.V10-078) .

NOTE: There is no retainer for the forward center bolt. Lockwire is used to safety the bolt head.

(2) Install the bolts (16), the washers (15), the retainers (10) and the nuts (14).
(3) Put the nut (3) and retainer (4) in position.
(4) Install the washer (5) and nut (6).
(5) TORQUE the nut (6) to between 0.45 and 0.39 m.daN (39.82 and 34.51 lbf.in )

.
(a) Apply torque stripe to the nut (6).
(6) Install the bolt (1) and washer (2) on the middle front engine mount.
(7) Tighten the bolts (1) and (16) with a standard wrench.

NOTE: You must install the washers (15) and (2) with the recessed side against the bolt head.

(8) Hold the nut (14) stable with a wrench and torque the bolts (1) and (16) to between 17.99 and 11.99 m.daN (132.67 and 88.42 lbf.ft )

CAUTION: MAKE SURE THAT THE TORQUE WRENCH DOES NOT TOUCH THE FORWARD ENGINE MOUNT DURING TIGHTENING TO NOT CHANGE THE TORQUE APPLIED TO THE BOLTS.

(9) Use the 98D71203001000 CHEST,TORQUE SET-ENGINE R I to torque the forward mount bolts:
(a) TORQUE the forward mount bolts to the final torque value to between 47.45 and 43.39 m.daN (349.93 and 319.99 lbf.ft )

(Ref. AMM TASK 70-23-11-911-013).

NOTE: The given torque values take into account the length of the torque wrench.

(10) Use the Torque wrench to torque the four forward mount bolts (16).
(11) Use the Torque wrench and Load Reducer to torque the center bolt (1) of the forward mount.

NOTE: The use of the load reducer (P/N GA184A) with the torque wrench (P/N TQFRM14) changes the value of the torque selected. You must set a value between 13 m.daN (95.87 lbf.ft) and 14 m.daN (103.24 lbf.ft) on the wrench to get the torque required for the forward center mount bolt.

NOTE: After you tighten the engine mount bolts to final torque, make sure that the surfaces between the pylon and the forward engine mount are in contact.

(12) Installation of the safety cable.

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(a) Install safety cable kit (Material No.V02-275) (Ref. AMM TASK 70-40-11-911-016) on center bolt (1).
Alternate: Use lockwire (Material No.V02-147) (Ref. AMM TASK 70-40-11-911-014), safety cable kit (Material No.V02-272) , safety cable kit (Material No.V02-273) , safety cable kit (Material No.V02-274) , safety cable kit (Material No.V02-276) , safety cable kit (Material No.V02-277) , safety cable (Material No.V02-278) ,
safety cable kit (Material No.V02-279) , safety cable ferrule (Material No.V02-280) or safety cable ferrule (Material No.V02-281) (Ref. AMM TASK 70-40-11-911-016).

NOTE: You can use lockwire diameters ranging from 0.8 mm to 1.2 mm (0.031 to 0.047 in.) to safety the bolt.

(13) Install the retainers (9) and (11) with bolt (7), washers (8) and (12) and nut (13).
(14) TORQUE the bolts (7) to between 0.40 and 0.27 m.daN (35.40 and 23.89 lbf.in )

(Ref. AMM TASK 70-23-11-911-013).
(15) Apply torque stripe to the nuts (13) and (14).

5. Close-up
Subtask 71-21-12-410-059-A ** ON A/C NOT FOR ALL

A. Close the thrust reverser cowl doors (Ref. AMM TASK 78-32-00-410-010):
(1) FOR [1000EM1] (ENGINE-1)
451AL, 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL, 462AR.

Subtask 71-21-12-440-054-A ** ON A/C NOT FOR ALL

B. Activate the thrust reverser hydraulic control unit (HCU) (Ref. AMM TASK 78-30-00-440-012).

Subtask 71-21-12-410-060-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL, 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL, 448AR.
(3) Remove the WARNING NOTICE(S).
(4) On panel 114VU, remove the locking tool from the flap and slat control lever.

[Rev.10 from 2021] 2026.04.01 12:56:27 UTC