Installation of the Engine Fuel/Oil Heat Exchanger Bypass Valve [PW11]

TASK 79-21-09-400-801-A
Installation of the Engine Fuel/Oil Heat Exchanger Bypass Valve

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.

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

ZONE: 400
FIN: 4019KS ** ON A/C NOT FOR ALL

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)
No specific	1	PLIERS - JAWED, SOFT
No specific	Torque wrench: range to between 90 and 80 lbf.in (1.02 and 0.90 m.daN )

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
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
2	FACE SEAL	EIPC 79-21-09-01-090

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-720-811-A	Test No. 3A - Idle Power Test
TASK 71-00-00-860-832-A	Procedure to Prevent Engine Motoring and to Stop the Electrical Supply to the EEC
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 73-25-34-400-802-A	Installation of the Engine Interface Unit (EIU)
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
TASK 79-00-00-610-801-A	Check and Fill the Engine Oil
Engine Fuel/Oil Heat Exchanger Bypass Valve

3. Job Set-up
Subtask 79-21-09-941-051-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Make sure that you did the procedure to prevent engine motoring and to stop the electrical supply to the Electronic Engine Control (EEC)
(Ref. AMM TASK 71-00-00-860-832).

Subtask 79-21-09-010-052-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Make sure that the fan cowl doors are open (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) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.

Subtask 79-21-09-040-051-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser System 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) Make sure that you did the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 79-21-09-010-053-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Make sure that the left thrust reverser cowl-doors are open (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL

4. Procedure
Subtask 79-21-09-420-050-A ** ON A/C NOT FOR ALL

A. Installation of the Engine Fuel/Oil Heat Exchanger Bypass Valve
(1) Removal of the protection covers

CAUTION: REMOVE THE PROTECTION COVERS FROM THE OPENINGS AS NECESSARY TO PREVENT ENGINE DAMAGE.

(a) Make sure that you remove all the necessary COVER - PROTECTION to prevent damage to the engine.

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

(2) Install the valve (1) on the fuel/oil manifold as follows:

Engine Fuel/Oil Heat Exchanger Bypass Valve ** ON A/C NOT FOR ALL

(a) Inspect the current face seal (2) for reusability as follows:
1 There is no raised material on the metal surface.
2 Rubber that is not bonded to the seal plate is not permitted.
3 Rubber that is missing is not permitted.
4 Inspect the rubber seal for separation from the seal plate.
5 Rubber that is cut or damaged is not permitted.
6 Make sure the rubber material is above the metal surface.
(b) Align and install the EIPC 79-21-09-01-090 FACE SEAL (2) on the fuel/oil manifold.
(c) Install the valve (1) on the fuel/oil manifold with the six bolts (3) and washers (4).
(d) TORQUE the six bolts (3) to between 90 and 80 lbf.in (1.02 and 0.90 m.daN )

equally in an opposite pattern until the same torque indication holds.
(3) Connect the wiring harness (WC10) connector (P52) to the bypass valve receptacle (J52) as follows:

Engine Fuel/Oil Heat Exchanger Bypass Valve ** ON A/C NOT FOR ALL

(a) Examine, align and engage the connector.
(b) Push lightly inward on the connector while you tighten the coupling ring.
(c) Use the PLIERS - JAWED, SOFT to tighten the connector against the receptacle.
(d) While you tighten, push the connector in and from side to side.
(e) Make sure that you can feel the ratchet feature.
(f) Tighten the connector until the PLIERS - JAWED, SOFT slip on the connector ring.

Subtask 79-21-09-612-050-A ** ON A/C NOT FOR ALL

B. Fill the engine with oil (Ref. AMM TASK 79-00-00-610-801).

5. Close-up
Subtask 79-21-09-410-050-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 left thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL

Subtask 79-21-09-440-050-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 79-21-09-410-051-A ** ON A/C NOT FOR ALL

C. Close Access
(1) 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
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
(4) Make sure that all the circuit breakers shown in the paragraph Procedure of the engine interface unit installation are closed. If they are not, close them in the recommended sequence
(Ref. AMM TASK 73-25-34-400-802).

Subtask 79-21-09-710-050-A ** ON A/C NOT FOR ALL

D. Test
(1) Do the test No. 3 - Idle Power Test (Ref. AMM TASK 71-00-00-720-811).

[Rev.10 from 2021] 2026.04.01 03:41:42 UTC