Replacement of the Helical Coil Insert(s) on the High Pressure Compressor (HPC) Front Case [PW11]
TASK 72-35-01-920-801-A
Replacement of the Helical Coil Insert(s) on the High Pressure Compressor (HPC) Front Case
Use this procedure to repair loose or damaged helical coil insert(s) on the HPC.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Expendable Parts
D. Referenced Information
3. Job Set-up
Subtask 72-35-01-941-050-A ** ON A/C NOT FOR ALL
Subtask 72-35-01-920-050-A ** ON A/C NOT FOR ALL
Subtask 72-35-01-410-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:49:21 UTC
Replacement of the Helical Coil Insert(s) on the High Pressure Compressor (HPC) Front Case
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:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
1. Reason for the JobUse this procedure to repair loose or damaged helical coil insert(s) on the HPC.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1) | |
| 437AL, 438AR, 451AL, 452AR | |
| FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2) | |
| 447AL, 448AR, 461AL, 462AR | |
| FIG.ITEM | DESIGNATION | IPC-CSN |
|---|---|---|
| 2 | INSERT OPTION | EIPC 72-35-01-01-120 |
| 1 | INSERT OPTION | EIPC 72-35-01-01-130 |
| 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 |
Subtask 72-35-01-941-050-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 72-35-01-010-050-A ** ON A/C NOT FOR ALL (1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
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 72-35-01-040-050-A ** ON A/C NOT FOR ALL (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.
C. Deactivation of the Thrust Reverser for Ground Maintenance
Subtask 72-35-01-010-051-A ** ON A/C NOT FOR ALL 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). 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(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.
Subtask 72-35-01-920-050-A ** ON A/C NOT FOR ALL
A. Replacement of the Helical Coil Insert(s) on the High Pressure Compressor (HPC) Front Case
(2) Do a visual inspection of the helical coil threaded insert hole(s) for thread damage.
(3) Install the new EIPC 72-35-01-01-130 INSERT OPTION (1) or new EIPC 72-35-01-01-120 INSERT OPTION (2) by SPOP 415 (Ref. AMM TASK 70-24-00-910-803), except it is not permitted to drill or tap.
(4) Do a visual inspection of the repaired area(s).
(5) Examine the assembly for foreign objects, damage and correct assembly.
5. Close-upCAUTION:
WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.
(1) Remove the loose or damaged helical coil insert(s) from the HPC front case by SPOP 415 (Ref. AMM TASK 70-24-00-910-803). (2) Do a visual inspection of the helical coil threaded insert hole(s) for thread damage.
(3) Install the new EIPC 72-35-01-01-130 INSERT OPTION (1) or new EIPC 72-35-01-01-120 INSERT OPTION (2) by SPOP 415 (Ref. AMM TASK 70-24-00-910-803), except it is not permitted to drill or tap.
(4) Do a visual inspection of the repaired area(s).
(5) Examine the assembly for foreign objects, damage and correct assembly.
Subtask 72-35-01-410-050-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 72-35-01-440-050-A ** ON A/C NOT FOR ALL (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.
B. Do the reactivation of the thrust reverser system after ground maintenance (Ref. AMM TASK 78-30-00-440-805).
Subtask 72-35-01-410-051-A ** ON A/C NOT FOR ALL
Helical Coil Insert(s) on the High Pressure Compressor (HPC) Front Case