Special Detailed Inspection (TC) of Forward Engine Mount Pylon Bolts [PW11]

TASK 71-21-41-220-806-A
Special Detailed Inspection (TC) of Forward Engine Mount Pylon Bolts

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

WARNING: ALWAYS USE APPLICABLE GLOVES TO TOUCH HOT PARTS. HOT PARTS CAN CAUSE INJURY TO PERSONS.

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

ZONE: 400

1. Reason for the Job
Refer to the MPD TASK: 712123-01
SPECIAL DETAILED INSPECTION (TC) OF FORWARD ENGINE MOUNT PYLON BOLTS.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	Torque wrench: range to between 0.47 and 0.37 m.daN (41.59 and 32.74 lbf.in )
No specific	Torque wrench: range to between 40 and 32.8 m.daN (294.99 and 241.89 lbf.ft )
98D71203013000	1	TORQUE WRENCH SET PW

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.P05-005)	lint-free cotton cloth

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 71-21-41-000-807-A	Removal of the Forward Mount Bolt (One at a time)
TASK 71-21-41-400-807-A	Installation of the Forward Mount Bolt (One at a time)
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
Special Detailed Inspection (TC) of Forward Engine Mount Pylon Bolts

3. Job Set-up
Subtask 71-21-41-941-061-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 71-21-41-010-081-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.

Subtask 71-21-41-040-061-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser for Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 71-21-41-010-082-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR

4. Procedure
Subtask 71-21-41-220-052-A ** ON A/C NOT FOR ALL

A. Special Detailed Inspection (Torque Check) of the Forward Engine-Mount Bolts

NOTE: This procedure is written for only one external forward mount screw. Apply this procedure to each external forward mount screws.

NOTE: Do not loosen the screw before to make the torque check.

(1) Get access to the forward engine mount at 12 o'clock area (engine junction area).
(2) Clean any dirt or unwanted material from the forward engine mount with a lint-free cotton cloth (Material No.P05-005) .
(3) Torque check of the forward engine mount bolt (3):
(a) Remove the Locking Plates system of the forward Engine Mounts.
1 Remove the four screws (1) that attach the four locking plates (2) to the retainer.
2 Remove the four locking plates (2).
3 Visually examine the four screws (1), the four locking plates (2) and the retainer for indication of damage.

If there are scratches, marks and/or other damage, reject the parts.

(b) Measure the torque of the forward mount bolt (3).
1 TORQUE value of the bolt (3) must be to between 40 and 32.8 m.daN (294.99 and 241.89 lbf.ft )

.
2 Use the tool 98D71203013000 TORQUE WRENCH SET PW to torque the bolts.
3 If the bolts (3) turn or if the torque value is less than the required torque value, replace all four Forward engine mount bolts (one at a time) (Ref. AMM TASK 71-21-41-000-807) and (Ref. AMM TASK 71-21-41-400-807).
4 If the torque value is correct, do the following procedure:
a Install the locking plates (2) and attach them to the retainer brackets with the screws (1).
b TORQUE the screws (1) to between 0.47 and 0.37 m.daN (41.59 and 32.74 lbf.in )

5. Close-up
Subtask 71-21-41-410-075-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR

Subtask 71-21-41-440-058-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 71-21-41-410-076-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:33:11 UTC