Installation of the ACT Pressure Holding Valve

TASK 28-28-48-400-001-A
Installation of the ACT Pressure Holding Valve

WARNING: BEFORE YOU DO WORK IN OR NEAR A FUEL TANK, MAKE SURE THAT YOU OBEY ALL THE SAFETY PROCEDURES. THIS WILL PREVENT INJURY TO PERSONS AND/OR DAMAGE TO THE AIRCRAFT.

WARNING: BE CAREFUL NOT TO GET AIRCRAFT FUEL IN YOUR MOUTH OR IN YOUR EYES. IF YOU GET FUEL ON YOUR SKIN OR ON YOUR CLOTHES, FLUSH IT IMMEDIATELY WITH WATER. IF NECESSARY, GET MEDICAL HELP. AIRCRAFT FUEL IS POISONOUS.

WARNING: DO NOT GET YOUR CLOTHES SOAKED WITH FUEL.

WARNING: MAKE SURE THAT YOU HAVE THE CORRECT FIRE FIGHTING EQUIPMENT AVAILABLE.

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	WARNING NOTICE(S)

B. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 28-00-00-910-001-A	Fuel Safety Procedures
TASK 28-10-00-910-001-A	Safety Procedures When You Do Work in a Fuel Tank
TASK 28-11-27-000-001-A	Removal of the Additional Center Tank (ACT)
TASK 28-11-27-400-001-A	Installation of the Additional Center Tank (ACT)
TASK 28-11-37-000-001-A	Removal of the Inner Manhole-Cover ACT
TASK 28-11-37-000-004-A	Removal of the Outer Manhole-Cover ACT
TASK 28-11-37-400-001-A	Installation of the Inner Manhole-Cover ACT
TASK 28-11-37-400-004-A	Installation of the Outer Manhole Cover ACT
TASK 28-25-00-650-005-A	To Drain the Remaining Fuel from the Additional Center Tank (ACT)

3. Job Set-up
Subtask 28-28-48-860-051-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Obey the fuel safety procedures (Ref. AMM TASK 28-00-00-910-001).
(2) Make sure that the ground service network is energized
(3) Make sure that the WARNING NOTICE(S) are in position on:

the refuel/defuel control panel 801VU,
the fuel control panel 40VU,
to tell persons not to operate the refuel/defuel system.

(4) Make sure that the applicable ACT is fully drained (Ref. AMM TASK 28-25-00-650-005).

NOTE: To install equipment inside of an ACT, first make sure that the ACT is removed from the aircraft.

(5) Make sure that the applicable Additional Center Tank (ACT) is removed (Ref. AMM TASK 28-11-27-000-001).
(6) Make sure that the applicable ACT Manhole Covers are removed (Ref. AMM TASK 28-11-37-000-004) (Ref. AMM TASK 28-11-37-000-001).

4. Procedure
Subtask 28-28-48-410-051-A ** ON A/C NOT FOR ALL

A. Preparation for Installation
(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.

Subtask 28-28-48-420-050-A ** ON A/C NOT FOR ALL

B. Installation of the Pressure Holding Valve

NOTE: This procedure must be done in the workshop only because of the possibility that the bladder tank can be damaged.

(1) Obey the safety procedures when you work in a fuel tank (Ref. AMM TASK 28-10-00-910-001).
(2) Install the pressure holding valve in the workshop.

5. Close-up
Subtask 28-28-48-410-050-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Install the ACT Manhole Covers (Ref. AMM TASK 28-11-37-400-001) (Ref. AMM TASK 28-11-37-400-004).
(2) Install the Additional Center Tank (ACT) in the AFT cargo compartment (Ref. AMM TASK 28-11-27-400-001).

Subtask 28-28-48-860-052-A ** ON A/C NOT FOR ALL

B. Put the aircraft back to the serviceable condition.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the WARNING NOTICE(S).
(3) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001)

[Rev.10 from 2021] 2026.04.02 06:17:59 UTC