Replacement of the Helical Coil Insert(s) on the High Pressure Turbine (HPT) Case [PW11]

TASK 72-51-01-920-801-A
Replacement of the Helical Coil Insert(s) on the High Pressure Turbine (HPT) Case

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.

ZONE: 400

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE

B. 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

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
1	INSERT OPTION	EIPC 72-52-01-01-120

D. Referenced Information

REFERENCE	DESIGNATION
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 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
Helical Coil Insert(s) on the HPT Case

3. Job Set-up
Subtask 72-51-01-941-050-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 72-51-01-010-050-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 1M (3 FT)-ADJUSTABLE in position.

Subtask 72-51-01-040-050-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 72-51-01-010-051-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 72-51-01-920-050-A ** ON A/C NOT FOR ALL

A. Replacement of the Helical Coil Insert(s) on the HPT Case

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

(1) Remove all external attachments that are necessary to help with the removal and installation of the helical coil inserts (1).
(2) Remove the loose or damaged helical coil insert(s) from the HPT case by SPOP 415 (Ref. AMM TASK 70-24-00-910-803).
(3) Do a visual inspection of the helical coil threaded insert hole(s) for thread damage.
(4) Install the new EIPC 72-52-01-01-120 INSERT OPTION (1) by SPOP 415 (Ref. AMM TASK 70-24-00-910-803).

Helical Coil Insert(s) on the HPT Case ** ON A/C NOT FOR ALL

(a) Installation of oversize inserts or twin inserts is not permitted.
(b) The top face of the first coil must be between 1.0 in. (25.40 mm) and 1.5 in. (38.10 mm) pitch below surface G. See sheet 1 of the figure:

Helical Coil Insert(s) on the HPT Case ** ON A/C NOT FOR ALL

(c) Break off the tang at the notch.
(5) Do a visual inspection of the repaired area(s).
(6) Install all the external attachments that were removed before the helical coil insert (1) removal and installation procedure.
(7) Examine the assembly for foreign objects, damage and correct assembly.

5. Close-up
Subtask 72-51-01-410-050-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 72-51-01-440-050-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 72-51-01-410-051-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Remove the access platform(s).
(2) 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
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:49:40 UTC