Removal of the Priority Valve of the Blue Hydraulic System

TASK 29-12-33-000-001-A
Removal of the Priority Valve of the Blue 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.

FIN: 2064GM

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	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
195BB

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
Priority Valve on HP Manifold with P/N series D29070173
Priority Valve on HP Manifold with P/N series 1554A9900

3. Job Set-up
Subtask 29-12-33-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	HYD/HYD PWR/B WARN/& CTL	2702GJ	C12
121VU	HYDRAULIC/LOW/LVL/IND	1832GQ	N32
121VU	HYDRAULIC/HYD/QTY/IND	1831GQ	P35
123VU	B HYD/ELEC PUMP	2701GJ	AB09

Subtask 29-12-33-010-051-A

B. Open the access panel 195BB.

Subtask 29-12-33-860-050-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 Blue hydraulic system:

In the cockpit on the hydraulic section 40VU of the overhead panel
On the ground service panel of the Blue hydraulic system.

(3) Make sure that the Blue hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
(4) Depresssurize the reservoir of the Blue hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(5) Put a CONTAINER 1 L (1/4 USGAL) below the HP manifold of the Blue hydraulic system.

4. Procedure
Subtask 29-12-33-020-050-A

A. Removal of the Priority Valve
(1) Hold the priority valve (1) and remove the bolts (2) and the washers (3).
(2) Remove the priority valve (1).
(3) Remove the bobbins (5) (Ref. AMM TASK 20-23-21-911-001).
(4) Install the PLUG - BLANKING in the ports of the priority valve (1) and in the HP manifold.

[Rev.10 from 2021] 2026.04.01 00:19:05 UTC