Cleaning of the Oil Cooler - Removed Oil Cooler (APS 3200)

TASK 49-91-44-100-002-A-01
Cleaning of the Oil Cooler - Removed Oil Cooler (APS 3200)

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

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

WARNING: WHEN YOU USE COMPRESSED AIR:

USE THE CORRECT PROTECTION (FACE SHIELD OR GOGGLES)
DO NOT POINT THE AIRFLOW AT YOURSELF OR OTHER PERSONS.

LOOSE PARTICLES AND/OR HIGH PRESSURE AIR CAN CAUSE INJURY.

WARNING: LOCK THE MECHANISM OF THE ACCESS DOOR 316AR WITH THE PIP PIN WHEN YOU OPEN THE ACCESS DOOR. THIS WILL PREVENT INJURY.

WARNING: MAKE SURE THAT THE SAFETY DEVICES AND THE WARNING NOTICES ARE IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

CAUTION: PUT PLASTIC CAPS OR PLUGS ON ALL FUEL AND/OR LUBRICATION SYSTEM COMPONENTS AND LINES. IF YOU USE TAPE, CLOTH, OR METAL CAPS ON THEM, YOU CAN DAMAGE THE APU.

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	1	AIR SOURCE 1.7 TO 2 BAR (25 TO 30 PSI) - FILTERED, DRY
No specific	1	CLEANING EQUIPMENT - STEAM
No specific	1	CONTAINER 10 L(2 1/2 USGAL)
No specific	1	LIGHT SOURCE - INSPECTION
No specific	1	OVEN - CURING, PORTABLE
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
No specific	AR	WATER - WARM, CLEAN

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08AJA9)	Aqueous Cleaner-Turbine Engine Gas Path - Legacy

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

D. Referenced Information

REFERENCE	DESIGNATION
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 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-00-00-860-005-A	APU Start by External Power
TASK 49-00-00-860-005-A-01	APU Start by Batteries
TASK 49-00-00-860-006-A	APU Shutdown by External Power
TASK 49-00-00-860-006-A-01	APU Shutdown by Batteries
TASK 49-20-00-600-002-A	Preservation/Storage/Return-to-Service of the APU (APS 3200)
TASK 49-91-44-000-003-A	Removal of the Oil Cooler (APS 3200)
TASK 49-91-44-400-003-A	Installation of the Oil Cooler (APS 3200)
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access

3. Job Set-up
Subtask 49-91-44-860-070-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) On panel 25VU, make sure that the APU MASTER SW pushbutton switch is in the OFF position.
(3) Put a WARNING NOTICE(S) 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 49-91-44-865-080-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 49-91-44-010-064-A ** ON A/C NOT FOR ALL

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

4. Procedure
Subtask 49-91-44-140-052-A ** ON A/C NOT FOR ALL

A. Cleaning of the Oil Cooler

NOTE: There are two procedures to clean the oil cooler, cleaning by immersion or cleaning with steam.

(1) Cleaning by immersion:
(a) Remove the oil cooler (Ref. AMM TASK 49-91-44-000-003).
(b) Put a PLUG - BLANKING on the oil inlet and outlet ports.
(c) Obey the manufacturer's instructions and prepare the cleaning agent.
(d) Put sufficient Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) into a CONTAINER 10 L(2 1/2 USGAL) to make sure that you can fully immerse the oil cooler.
(e) If the oil cooler has a large quantity of contamination, refer to the manufacturer's instructions and increase the temperature of the cleaning agent to the recommended temperature.
(f) Soak the oil cooler:

CAUTION: DO NOT LET THE OIL COOLER STAY IN THE CLEANING AGENT FOR MORE THAN FOUR HOURS. AFTER THIS TIME, THE CLEANING AGENT WILL CAUSE DAMAGE TO THE OIL COOLER COVERING.

1 Soak the oil cooler in the cleaning agent for a maximum of four hours.
(g) Shake the oil cooler to remove all remaining air.
(h) Flush the cleaning agent through the cooler matrix to make the cleaning procedure faster.
(i) Remove the oil cooler from the cleaning tank and drain it fully.
(j) Flush the oil cooler with WATER - WARM, CLEAN.
(k) Remove the PLUG - BLANKING from the oil inlet and outlet ports and flush the oil cooler with WATER - WARM, CLEAN continuously for no less than three minutes.
(l) Do a visual inspection as given in Para. (3).
(2) Cleaning with steam:

CAUTION: KEEP THE WAND TIP 30 CENTIMETERS (12 INCHES) AWAY FROM THE OIL COOLER MATRIX. THE STEAM PRESSURE FROM THE WAND CAN BEND THE MATRIX VANES AND REMOVE THE PROTECTIVE COATING.

(a) Remove the oil cooler (Ref. AMM TASK 49-91-44-000-003).
(b) Put a PLUG - BLANKING on the oil inlet and outlet ports.
(c) Obey the manufacturer's instructions and prepare the steam cleaning solution.
(d) If the oil cooler has a large quantity of contamination, add a small quantity of Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) to the water to help remove it.
(e) Flush the air sections with the CLEANING EQUIPMENT - STEAM at a pressure value of between 20 psi (1.38 bar) and 30 psi (2.07 bar).
(f) Remove the PLUG - BLANKING from the oil inlet and outlet ports.
(g) Flush the oil sections fully at a pressure value of between 30 psi (2.07 bar) and 50 psi (3.45 bar) for 15 minutes in each direction of flow. Continue until the steam cleaning solution that flows out of the sections is clean.
(h) Flush the oil cooler with WATER - WARM, CLEAN until the steam cleaning solution is fully removed.
(3) Visual inspection of the oil cooler:
(a) Point a LIGHT SOURCE - INSPECTION through the matrix and make sure that the oil cooler is clean.
1 If you find contamination, do the cleaning procedure again unless the total time that you soaked the oil cooler was four hours.
a If you cannot clean the oil cooler fully, return the oil cooler to the workshop.
2 If you do not find contamination, dry the oil cooler.
(4) Dry the oil cooler:

CAUTION: DO THE DRYING PROCEDURE MAXIMUM FOUR HOURS AFTER THE WET CLEANING PROCEDURE TO PREVENT CORROSION.

(a) Remove as much water as possible from the oil cooler with AIR SOURCE 1.7 TO 2 BAR (25 TO 30 PSI) - FILTERED, DRY.
(b) If you install the oil cooler on an APU that will be in storage:

WARNING: USE THERMAL GLOVES WHEN YOU MOVE OR TOUCH HOT OR COLD PARTS. HOT OR COLD PARTS CAN CAUSE INJURY.

1 Dry the oil cooler in a OVEN - CURING, PORTABLE at a temperature of 149 deg.C (300 deg.F) for a minimum of 30 minutes or until no more steam comes from the oil cooler.
2 Remove the oil cooler from the OVEN - CURING, PORTABLE and while hot, blow compressed air with an AIR SOURCE 1.7 TO 2 BAR (25 TO 30 PSI) - FILTERED, DRY through it to fully dry it.
3 If necessary, dry the oil cooler again until it is fully dry.
4 Install the oil cooler (Ref. AMM TASK 49-91-44-400-003).
5 Do the preservation/storage procedure of the APU (Ref. AMM TASK 49-20-00-600-002).
(c) If you install the oil cooler on an APU installed in the aircraft:
1 Blow compressed air with and AIR SOURCE 1.7 TO 2 BAR (25 TO 30 PSI) - FILTERED, DRY through the oil cooler to dry it.
2 Install the oil cooler (Ref. AMM TASK 49-91-44-400-003).
3 Start and operate the APU for 15 minutes to fully dry the oil cooler (Ref. AMM TASK 49-00-00-860-005).
4 Stop the APU (Ref. AMM TASK 49-00-00-860-006).

5. Close-up
Subtask 49-91-44-410-061-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
(2) Make sure that the work area is clean and clear of tools and other items.
(3) Set LIGHT control switch 11LJ to the OFF position.
(4) Close APU access doors 315AL and 316AR (Ref. AMM TASK 52-41-00-410-001).
(5) Remove the access platform(s).

Subtask 49-91-44-865-081-A ** ON A/C NOT FOR ALL

B. Remove the safety clip(s) and the tag(s) and close 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 49-91-44-860-071-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(2) Put the aircraft back to its initial configuration.
(3) Remove the WARNING NOTICE(S).

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