Installation of the Buffer Air Valve Solenoid [PW11]

TASK 75-26-04-400-801-A
Installation of the Buffer Air Valve Solenoid

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE 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.

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	1	PLIERS - JAWED, SOFT
No specific	Torque wrench: range to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )
No specific	Torque wrench: range to between 225 and 200 lbf.in (2.54 and 2.26 m.daN )
No specific	Torque wrench: range to between 375 and 340 lbf.in (4.24 and 3.84 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.P06-054)	Antigalling Compound

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 462AR

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
Buffer Air Valve Solenoid

3. Job Set-up
Subtask 75-26-04-941-051-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 75-26-04-010-052-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

Subtask 75-26-04-040-051-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 75-26-04-010-053-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Make sure that the right thrust reverser cowl-door is open (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

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

Subtask 75-26-04-420-050-A ** ON A/C NOT FOR ALL

A. Installation of the Buffer Air Valve Solenoid
(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.
(2) Install the buffer air valve solenoid (1) as follows. See

Buffer Air Valve Solenoid ** ON A/C NOT FOR ALL

(a) Apply Antigalling Compound (Material No.P06-054) to the threads of the four captive bolts.
(b) Install the solenoid (1) on the bracket on the Compressor Intermediate Case (CIC) with the four captive bolts.
(c) TORQUE the four captive bolts to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )

.
(3) Connect the two actuation air tubes (AA15) and (AA25) to the solenoid (1) as follows:
(a) Apply Antigalling Compound (Material No.P06-054) to the threads of the two tube adapters.
(b) Connect the two tubes (AA15) and (AA25) to the solenoid (1).
(c) Torque the tube (AA15) as follows:

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 TORQUE the B-nut to between 375 and 340 lbf.in (4.24 and 3.84 m.daN )

.
(d) Torque the tube (AA25) as follows:

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 TORQUE the B-nut to between 225 and 200 lbf.in (2.54 and 2.26 m.daN )

.
(4) Connect the (WC08) wiring harness (4094KS) connector (P21) to the solenoid receptacle (J21) as follows:

CAUTION: MAKE SURE THAT THE ELECTRICAL CONNECTOR AND RECEPTACLE ARE CLEAN WHEN YOU CONNECT THEM. DIRTY CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.

(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) Make sure that you can feel the ratchet feature.
(e) While you tighten, push the connector in and from side to side.
(f) Tighten the connector until the PLIERS - JAWED, SOFT slip on the connector ring.
(5) Examine the assembly for foreign objects, damage, and correct assembly.

5. Close-up
Subtask 75-26-04-410-050-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 right thrust reverser cowl-door (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
462AR

Subtask 75-26-04-440-050-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 75-26-04-410-051-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 WARNING NOTICE(S).
(3) 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 75-26-04-720-050-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 03:13:21 UTC