Removal of the Compressor Inlet Gasket

TASK 21-52-21-000-002-A
Removal of the Compressor Inlet Gasket

WARNING: MAKE SURE THAT AIR IS NOT SUPPLIED TO THE AIR CONDITIONING SYSTEM FROM THE MAIN ENGINE, THE APU OR A GROUND SOURCE. HOT COMPRESSED AIR CAN CAUSE INJURY TO PERSONNEL.

WARNING: BE CAREFUL WHEN YOU REMOVE OR INSTALL THIS EQUIPMENT. THIS EQUIPMENT IS HEAVY (MORE THAN 12 KG (26.5 lb)) AND CAN CAUSE INJURY AND/OR DAMAGE.

NOTE: This procedure is applicable for the air-cycle machine with part numbers 1263A0000-02/-03, 757A0000-08/-09/-10 and 1263C0000-01.

FIN: 10HM1
FIN: 11HM1

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	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [10HM1] (MACHINE-AIR CYCLE)
191KB
FOR [11HM1] (MACHINE-AIR CYCLE)
192KB

C. Referenced Information

REFERENCE	DESIGNATION
TASK 21-52-21-000-001-A	Removal of the Air Cycle Machine
TASK 21-52-23-000-002-A	Removal of the Pipe Assembly between the Anti-Ice Valve (if installed), the Bypass Valve and the Air Cycle Machine
TASK 21-61-53-000-001-A	Removal of the Turbine Bypass Valve
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 53-35-13-000-002-A	Removal of the Quick-Release Access Panels from the Belly Fairing Structure
Compressor Inlet Gasket on Part Number 1263A
Compressor Inlet Gasket on Part Number 757A
Compressor Inlet Gasket on Part Number 1263C

3. Job Set-up
Subtask 21-52-21-861-053-A

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 21-52-21-865-055-A

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 10HM1 (MACHINEAIR CYCLE)
49VU	AIR COND/TEMP CTL/SYS 1 CHAN B/28VDC	52HH	D08
** ON A/C NOT FOR ALL
122VU	AIR COND/PACK TEMP/CTL SYS1/1/115VAC	1HH	X22
122VU	AIR COND/PACK TEMP/CTL SYS1/1/28VDC	3HH	X21
122VU	AIR COND/PACK TEMP CTL SYS2/1/28VDC	4HH	Y19
122VU	AIR COND/PACK TEMP CTL SYS2/1/115VAC	2HH	Y18
** ON A/C NOT FOR ALL
122VU	AIR COND/TEMP CTL SYS 1/CHAN A/115VAC	49HH	X22
122VU	AIR COND/TEMP CTL SYS 1/CHAN A/28VDC	51HH	X21
122VU	AIR COND/TEMP CTL SYS 1/CHAN B/115VAC	50HH	Y18
** ON A/C NOT FOR ALL
FOR FIN: 11HM1 (MACHINEAIR CYCLE)
122VU	AIR COND/PACK TEMP/CTL SYS1/2/115VAC	21HH	W22
122VU	AIR COND/PACK TEMP/CTL SYS1/2/28VDC	23HH	W21
122VU	AIR COND/PACK TEMP CTL SYS2/2/28VDC	24HH	Y21
122VU	AIR COND/PACK TEMP CTL SYS2/2/115VAC	22HH	Y20
** ON A/C NOT FOR ALL
122VU	AIR COND/TEMP CTL SYS 2/CHAN A/115VAC	53HH	W22
122VU	AIR COND/TEMP CTL SYS 2/CHAN A/28VDC	55HH	W21
122VU	AIR COND/TEMP CTL SYS 2/CHAN B/28VDC	56HH	Y21
122VU	AIR COND/TEMP CTL SYS 2/CHAN B/115VAC	54HH	Y20

Subtask 21-52-21-941-051-A

C. Safety Precautions
(1) On AIR COND panel 30VU:
(a) Make sure that:

The APU BLEED pushbutton switch is released (the ON legend is off)
The ENG 1 BLEED and the ENG 2 BLEED pushbutton switches are released (the OFF legends are on).

(b) Put a WARNING NOTICE(S) in position to tell persons not to operate these pushbutton switches.
(2) On the HP ground connector, put the WARNING NOTICE(S) in position to tell persons not to supply the ground air.

Subtask 21-52-21-010-052-A

D. Get Access
(1) Remove these access panels from the belly fairing structure (Ref. AMM TASK 53-35-13-000-002):
(a) FOR [10HM1] (MACHINE-AIR CYCLE)

191KB.

(b) FOR [11HM1] (MACHINE-AIR CYCLE)

192KB.

(2) Remove the clamp from the pipe assembly between the compressor inlet duct and the primary heat exchanger (Ref. AMM TASK 21-52-21-000-001).
(3) If installed, remove the pipe assembly between the anti-ice valve, the bypass valve and the air cycle machine (Ref. AMM TASK 21-52-23-000-002).
(4) Remove bypass valve 10HH (11HH) (Ref. AMM TASK 21-61-53-000-001).

4. Procedure
Subtask 21-52-21-020-053-A

A. Removal of the Compressor Inlet Gasket

CAUTION: WHEN YOU REMOVE THE SCREWS, MAKE SURE THAT YOU DO NOT CAUSE DAMAGE TO THE SCREWLOCKS. IF YOU CAUSE DAMAGE TO THE SCREWLOCKS, YOU MUST REMOVE THE UNIT AND SEND IT TO AN APPROVED REPAIR STATION.

(1) For part number 1263A0000-02/-03:

Compressor Inlet Gasket on Part Number 1263A

(a) Remove the screws (5) and the washers (4).
(b) Remove the compressor inlet duct (3).
(c) Remove and discard the compressor inlet gasket (2).
(2) For part number 757A0000-08/-09/-10:

Compressor Inlet Gasket on Part Number 757A

(a) Remove the nuts (10) and the screws (6).
(b) Remove the compressor inlet duct (9).
(c) Remove and discard the packing (8).
(3) For part number 1263C0000-01:

Compressor Inlet Gasket on Part Number 1263C

(a) Remove the screws (5) and (7) and the washers (4) and (6).
(b) Remove the compressor inlet duct (3).
(c) Remove and discard the compressor inlet gasket (2).

[Rev.10 from 2021] 2026.04.02 06:11:27 UTC