Removal of the Pressure Relief Valve of the Green Hydraulic System

TASK 29-11-32-000-001-A
Removal of the Pressure Relief Valve of the Green Hydraulic System

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

ZONE: 147
FIN: 1063GM

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 3M (10 FT)
No specific	1	CONTAINER 1 L (1/4 USGAL)
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	2	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
147	MAIN GEAR WELL AND HYDRAULIC COMPARTMENT
197CB

C. Referenced Information

REFERENCE	DESIGNATION
TASK 20-23-21-911-001-A	Removal/Installation of the Bobbins from their Housings and Installation of O-rings, Square Seals, and Back-up Rings on the Bobbins
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-910-002-A	Safety Procedures of the Hydraulic System
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 29-23-00-860-001-A	Disconnection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
Pressure Relief Valve on HP Manifold with P/N series 1559A9900

3. Job Set-up
Subtask 29-11-32-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	HYDRAULIC/G HYD/PUMP ENG1/CTL	1701GK	H12
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/G HYD/PUMP ENG1/CTL	1701GK	R35
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/G HYD/PUMP ENG1/MONG	1702GK	R34
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/G HYD/PUMP ENG1/MONG	1702GK	R33

Subtask 29-11-32-010-050-A

B. Get Access
(1) Open the access door 197CB.
(2) Open one of the main doors of the main gear (Ref. AMM TASK 32-12-00-010-001).

Subtask 29-11-32-860-050-A

C. Aircraft Maintenance Configuration

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

(1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green hydraulic system:

In the cockpit on the overhead panel
On the ground service panel of the Green hydraulic system.

(3) Make sure that the Green hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
(4) Depressurize the reservoir of the Green hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(5) Put the ACCESS PLATFORM 3M (10 FT) in position at the main door of the main gear.
(6) Put a CONTAINER 1 L (1/4 USGAL) below the HP manifold of the Green hydraulic system.
(7) Disconnect the isolation coupling of the power transfer unit (PTU) (Ref. AMM TASK 29-23-00-860-001).

4. Procedure
Subtask 29-11-32-020-050-C

A. Removal of the Pressure Relief Valve

Pressure Relief Valve on HP Manifold with P/N series 1559A9900

(1) Remove the nut (9), the bolt (6) and the washer (7) and disconnect the bonding jumper (8).
(2) Hold the pressure relief valve (1) and remove the bolts (2) and the washers (3).
(3) Remove the pressure relief valve (1).
(4) Remove the bobbins (5) (Ref. AMM TASK 20-23-21-911-001).
(5) Install a PLUG - BLANKING in the ports of the pressure relief valve and the HP manifold. (1).

[Rev.10 from 2021] 2026.04.01 07:56:25 UTC