Removal of the Defuel/Transfer Valve

TASK 28-25-43-000-001-A
Removal of the Defuel/Transfer Valve

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

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: 142
ZONE: 148
FIN: 11QM

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	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	1	CONTAINER 10 L(2 1/2 USGAL)
No specific	AR	PLUG - BLANKING

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
142	WING CENTER BOX
148	MAIN GEAR WELL AND HYDRAULIC COMPARTMENT
148AZ

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 28-10-00-910-001-A	Safety Procedures When You Do Work in a Fuel Tank
TASK 28-10-00-910-002-A	Access to the Fuel Tanks and the Work Areas
TASK 28-25-00-650-001-A	Pressure Defuel
TASK 28-25-43-000-002-A	Removal of the Defuel/Transfer Valve - Drive Assembly
TASK 28-25-53-000-001-A	Removal of the Center-Tank Defuel/Transfer Valve-Actuator
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
TASK 57-17-11-000-001-A	Removal of Access Cover 147AZ(148AZ)
TASK 57-17-11-000-001-B	Removal of Access Cover 148AZ or/and the ACT-Equipment Support Door
Defuel/Transfer Valve of Center Tank

3. Job Set-up
Subtask 28-25-43-910-050-A

A. Safety Precautions

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

(1) You must obey the special fuel safety procedures when you work in the fuel tank (Ref. AMM TASK 28-10-00-910-001) (Ref. AMM TASK 28-10-00-910-002).

Subtask 28-25-43-650-050-A

B. Defuel the right wing and center tanks (Ref. AMM TASK 28-25-00-650-001).

Subtask 28-25-43-861-050-A

C. Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

Subtask 28-25-43-869-050-A

D. On the refuel/defuel control panel 800VU, make sure that:

the MODE SELECT switch is set to OFF
the OPEN warning light is off.

Subtask 28-25-43-862-050-A

E. De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).

Subtask 28-25-43-010-050-A

F. Removal for Access
(1) Open the main door of the right main gear (Ref. AMM TASK 32-12-00-010-001).
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the main door of the right main gear.
(3) Remove the manhole cover 148AZ (Ref. AMM TASK 57-17-11-000-001).
(4) Remove the valve actuator 11QU (Ref. AMM TASK 28-25-53-000-001).

4. Procedure
Subtask 28-25-43-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Defuel/Transfer Valve
(1) Put a CONTAINER 10 L(2 1/2 USGAL) below the valve (20).
(2) Remove the nuts (6), the washers (5) and the bolts (3) and disconnect the bonding strips (4) and (19).
(3) Remove the nuts (17) and the bolts (16).
(4) Remove the nuts (10) and the bolts (9).
(5) Loosen the nuts (13) (Ref. Detail C).
(6) Remove the screws (2).
(7) Engage the line (14) into the line (15) and the line (11) into the line (7).
(8) Remove the valve (20). Remove and discard the O-ring (21) and the O-rings (12).
(9) Put the PLUG-BLANKING in each disconnected line end.

Subtask 28-25-43-020-050-B ** ON A/C NOT FOR ALL

A. Removal of the Defuel/Transfer Valve
(1) Put a CONTAINER 10 L(2 1/2 USGAL) below the valve (20).
(2) Remove the nuts (6), the washers (5) and the bolts (3) and disconnect the bonding strips (4) and (19).
(3) Remove the nuts (17) and the bolts (16).
(4) Remove the nuts (10) and the bolts (9).
(5) Loosen the nuts (13) (Ref. Detail C).
(6) Remove the drive assembly (Ref. AMM TASK 28-25-43-000-002).
(7) Remove the screws (2).
(8) Engage the line (14) into the line (15) and the line (11) into the line (7).
(9) Remove the valve (20). Remove and discard the O-ring (21) and the O-rings (12).
(10) Put the PLUG-BLANKING in each disconnected line end.

[Rev.10 from 2021] 2026.04.02 06:17:40 UTC