Removal of the Oil Cooler (131-9(A))

TASK 49-91-44-000-004-A
Removal of the Oil Cooler (131-9(A))

WARNING: DO NOT TOUCH THE APU UNTIL IT IS SUFFICIENTLY COOL TO PREVENT BURNS WHEN YOU DO THE MAINTENANCE TASK(S).

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 4M (13 FT)-ADJUSTABLE
No specific	AR	CONTAINER 10 L(2 1/2 USGAL)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-91-44-000-802-A	Removal of the Oil-Cooler Transfer Tubes (131-9(A))
TASK 52-41-00-010-001-A	Open the APU Doors for Access
Oil Cooler

3. Job Set-up
Subtask 49-91-44-860-062-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(2) On the panel 25VU, make sure that the APU MASTER SW p/bsw is OFF.
(3) Put a warning notice in the cockpit to tell persons not to start the APU.
(4) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).

Subtask 49-91-44-865-070-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-91-44-010-059-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position below the APU access doors 315AL and 316AR.
(2) Open the APU access doors 315AL 316AR and (Ref. AMM TASK 52-41-00-010-001).
(3) Set the LIGHT control SW 11LJ to the ON position.

4. Procedure
Subtask 49-91-44-020-053-A ** ON A/C NOT FOR ALL

A. Removal of the Oil Cooler
(1) Remove the clamp (3) and disconnect the air outlet duct (4) from the oil cooler (2).
(2) Put blanking plugs on the disconnected duct (4) and the oil cooler (2).
(3) Disconnect the oil-cooler transfer tubes from the oil cooler (2) (Ref. AMM TASK 49-91-44-000-802).
(4) Loosen the captive bolts (1).
(5) Hold the oil cooler (2) while you loosen the bolts (5) and the captive nuts (6).
(6) Remove the oil cooler (2) from the APU.
(7) Put the oil cooler (2) over the CONTAINER 10 L(2 1/2 USGAL) and drain.

[Rev.10 from 2021] 2026.04.01 01:33:28 UTC