Replacement of the Helical Coil Insert(s) on the Main Gear Box (MGB) Assembly [PW11]

TASK 72-61-01-960-806-A
Replacement of the Helical Coil Insert(s) on the Main Gear Box (MGB) Assembly

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

CAUTION: THIS AIRCRAFT MAINTENANCE MANUAL REPAIR LETS YOU REPLACE ONLY THE ORIGINAL EQUIPMENT MANUFACTURER'S HELICAL COIL INSERT(S). IF THERE IS DAMAGE TO THE HOLE(S) AND AN OVERSIZED INSERT IS NECESSARY, THEN YOU MUST NOT DO THE REPAIR ON-WING. YOU MUST REMOVE AND REPAIR THE PART AS PER THE APPLICABLE CLEANING, INSPECTION & REPAIR MANUAL.

CAUTION: MAKE SURE THAT NO HELICAL COIL INSERT(S) OR DEBRIS GOES (GO) INTO THE ENGINE DURING THIS REPAIR PROCEDURE. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE ENGINE PARTS CAN OCCUR.

ZONE: 400

1. Reason for the Job
Use this repair procedure to remove and replace loose or damaged helical coil inserts on the Main Gear Box (MGB) assembly.
2. Job Set-up Information
A. 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

B. Referenced Information

REFERENCE	DESIGNATION
TASK 24-21-51-000-803-A	Removal of the Integrated Drive Generator - IDG 1(2)
TASK 24-21-51-400-803-A	Installation of the Integrated Drive Generator - IDG 1(2)
TASK 29-11-51-000-805-A	Removal of the Green Engine Driven Pump
TASK 29-11-51-400-805-A	Installation of the Green Engine-Driven Pump
TASK 29-13-51-000-806-A	Removal of the Yellow Engine Driven Pump
TASK 29-13-51-400-806-A	Installation of the Yellow Engine-Driven Pump
TASK 70-24-00-910-803-A	SPOP 415 - Installation of Helical Coil Threaded Inserts
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 71-71-01-000-802-A	Removal of the Engine Drain Mast
TASK 71-71-01-400-802-A	Installation of the Engine Drain Mast
TASK 71-71-49-000-801-A	Removal of the Engine Drain Tubes and Pylon Drain Hoses
TASK 71-71-49-400-801-A	Installation of the Engine Drain Tubes and Pylon Drain Hoses
TASK 72-62-01-000-801-A	Removal of the Angle Gearbox
TASK 72-62-01-400-801-A	Installation of the Angle Gearbox
TASK 73-11-01-000-801-A	Removal of the Integrated Fuel Pump and Control (IFPC)
TASK 73-11-01-400-801-A	Installation of the Integrated Fuel Pump and Control (IFPC)
TASK 73-11-02-000-801-A	Removal of the Fuel Manifold
TASK 73-11-02-400-801-A	Installation of the Fuel Manifold
TASK 73-13-02-000-801-A	Removal of the Fuel Return Pump
TASK 73-13-02-400-801-A	Installation of the Fuel Return Pump
TASK 73-21-05-000-801-A	Removal of the Permanent Magnet Alternator (PMA) Rotor
TASK 73-21-05-400-801-A	Installation of the Permanent Magnet Alternator (PMA) Rotor
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
TASK 79-21-01-000-801-A	Removal of the Lubrication and Scavenge Oil Pump
TASK 79-21-01-400-801-A	Installation of the Lubrication and Scavenge Oil Pump
TASK 79-21-02-000-801-A	Removal of the Oil Control Module
TASK 79-21-02-400-801-A	Installation of the Oil Control Module
TASK 79-21-15-000-801-A	Removal of the Variable Oil Reduction Valve (VORV)
TASK 79-21-15-400-801-A	Installation of the Variable Oil Reduction Valve (VORV)
TASK 80-11-01-000-801-A	Removal of the Starter
TASK 80-11-01-400-801-A	Installation of the Starter
Replacement of the Helical Coil Insert(s) on the Main Gear Box (MGB) Assembly

3. Job Set-up
Subtask 72-61-01-941-059-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 72-61-01-010-072-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.

Subtask 72-61-01-040-058-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser for Ground 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 ground maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 72-61-01-010-073-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

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

Subtask 72-61-01-960-051-A ** ON A/C NOT FOR ALL

A. Replacement of the Helical Coil Insert(s) on the Main Gear Box (MGB) Assembly
(1) Find the MGB attached to the engine at the 6 o'clock position.
(2) Remove all the external attachments that prevent the removal and the installation of the helical coil insert(s):
(a) Remove the engine drain mast (Ref. AMM TASK 71-71-01-000-802).
(b) Remove the drain tubes (FB02), (DR01), (DR11), (DR21), (DR22), (DR41), (DR51), (DR121) and (DR131) (Ref. AMM TASK 71-71-49-000-801).
(c) Remove the Integrated Drive Generator (IDG) (Ref. AMM TASK 24-21-51-000-803).
(d) Remove the Engine Driven Pump (EDP) (Ref. AMM TASK 29-11-51-000-805) and (Ref. AMM TASK 29-13-51-000-806).
(e) Remove the Integrated Fuel Pump and Control (IFPC) (Ref. AMM TASK 73-11-01-000-801).
(f) Remove the fuel return pump (Ref. AMM TASK 73-13-02-000-801).
(g) Remove the fuel oil manifold (Ref. AMM TASK 73-11-02-000-801).
(h) Remove the lubrication and scavenge oil pump (Ref. AMM TASK 79-21-01-000-801).
(i) Remove the Variable Oil Reduction Valve (VORV) (Ref. AMM TASK 79-21-15-000-801).
(j) Remove the oil control module (Ref. AMM TASK 79-21-02-000-801).
(k) Remove the Permanent Magnet Alternator (PMA) (Ref. AMM TASK 73-21-05-000-801).
(l) Remove the starter (Ref. AMM TASK 80-11-01-000-801).
(m) Remove the Angle Gearbox (AGB) (Ref. AMM TASK 72-62-01-000-801).
(3) Remove and discard the loose and/or damaged helical coil-insert(s) (1), (2), (3) or (4) from the MGB by SPOP 415 (Ref. AMM TASK 70-24-00-910-803).
(4) Do a visual inspection of the helical coil insert(s) (1), (2), (3) or (4) hole(s) for thread damage.
(a) No damage is permitted.
(5) Install a new helical coil insert(s) (1), (2), (3) or (4) on the MGB assembly by SPOP 415 (Ref. AMM TASK 70-24-00-910-803).
(a) Oversized inserts or twinserts are not permitted.
(b) For the location and identification of helical coil-insert part numbers, see the Table 1.

Index Number	Part Number
(1)	NAS1130-4FL20
(2)	NAS1130-6FL20
(3)	NAS1130-3L20
(4)	NAS1130-06L20

Table - Helical Coil-Insert Part Numbers

(6) Do a visual inspection of the installed helical coil insert(s) (1), (2), (3) or (4) to make sure that it(they) is(are) installed as specified in SPOP 415 (Ref. AMM TASK 70-24-00-910-803).
(7) Install all the external attachments that you removed at the step 4.A.(2):
(a) Install the Angle Gearbox (AGB) (Ref. AMM TASK 72-62-01-400-801).
(b) Install the starter (Ref. AMM TASK 80-11-01-400-801).
(c) Install the Permanent Magnet Alternator (PMA) (Ref. AMM TASK 73-21-05-400-801).
(d) Install the oil control module (Ref. AMM TASK 79-21-02-400-801).
(e) Install the Variable Oil Reduction Valve (VORV) (Ref. AMM TASK 79-21-15-400-801).
(f) Install the lubrication and scavenge oil pump (Ref. AMM TASK 79-21-01-400-801).
(g) Install the fuel oil manifold (Ref. AMM TASK 73-11-02-400-801).
(h) Install the fuel return pump (Ref. AMM TASK 73-13-02-400-801).
(i) Install the Integrated Fuel Pump and Control (IFPC) (Ref. AMM TASK 73-11-01-400-801).
(j) Install the Engine Driven Pump (EDP) (Ref. AMM TASK 29-11-51-400-805) and (Ref. AMM TASK 29-13-51-400-806).
(k) Install the Integrated Drive Generator (IDG) (Ref. AMM TASK 24-21-51-400-803).
(l) Install the drain tubes (FB02), (DR01), (DR11), (DR21), (DR22), (DR41), (DR51), (DR121) and (DR131) (Ref. AMM TASK 71-71-49-400-801).
(m) Install the engine drain mast (Ref. AMM TASK 71-71-01-400-802).
(8) Examine the assembly for the foreign objects, damage and correct assembly.

5. Close-up
Subtask 72-61-01-410-070-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 72-61-01-440-057-A ** ON A/C NOT FOR ALL

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

Subtask 72-61-01-410-071-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 WARNING NOTICE(S).
(3) Remove all the fixtures, tools, test and support equipment used during this procedure.

[Rev.10 from 2021] 2026.04.01 02:50:07 UTC