Removal of the Buffer Air Valve Solenoid [PW11]

TASK 75-26-04-000-801-A
Removal of the Buffer Air Valve Solenoid

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.

ZONE: 400
FIN: 4056KS ** 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	AR	PLIERS - JAWED, SOFT

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, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
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 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
Buffer Air Valve Solenoid

3. Job Set-up
Subtask 75-26-04-941-050-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do 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 75-26-04-010-050-A ** ON A/C NOT FOR ALL

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

Subtask 75-26-04-040-050-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser 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) Do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 75-26-04-010-051-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the right thrust reverser cowl-door (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
462AR.

4. Procedure
Subtask 75-26-04-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Buffer Air Valve Solenoid
(1) Find the buffer air valve solenoid (1) attached to the Compressor Intermediate Case (CIC) at the 5 o'clock position.
(2) Remove the buffer air valve solenoid (1) from the CIC as follows:
(a) Disconnect the (WC08) wiring harness (4094KS) connector (P21) from the buffer air valve solenoid (1) with the PLIERS - JAWED, SOFT.
(b) Disconnection of the two actuation air tubes:

CAUTION: USE A SECOND WRENCH TO HOLD THE MATING PARTS WHEN YOU LOOSEN OR TIGHTEN THE TUBE OR HOSE NUTS. IF YOU DO NOT OBEY THIS CAUTION, YOU CAN TWIST OR CAUSE DAMAGE TO THE TUBES OR HOSES.

1 While you hold the adapters with the wrench, disconnect the two actuation air tubes (AA15) and (AA25) from the buffer air valve solenoid (1).
(c) Loosen the four captive bolts.
(d) Remove the buffer air valve solenoid (1) from the bracket.

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

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

[Rev.10 from 2021] 2026.04.01 03:13:19 UTC