Removal of the Check Valve

TASK 28-12-44-000-005-A
Removal of the Check 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.

FIN: 173QM1 ** ON A/C NOT FOR ALL
FIN: 173QM2 ** 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	AR	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
826

C. Referenced Information

REFERENCE	DESIGNATION
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 28-11-27-000-001-A	Removal of the Additional Center Tank (ACT)
TASK 28-11-37-000-001-A	Removal of the Inner Manhole-Cover ACT
TASK 28-25-00-650-001-A	Pressure Defuel
TASK 28-25-00-650-005-A	To Drain the Remaining Fuel from the Additional Center Tank (ACT)
Check Valve 173QM1 ** ON A/C NOT FOR ALL
Check Valves 173QM1 and 173QM2 ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-12-44-941-069-A ** ON A/C NOT FOR ALL

A. Safety Precautions

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.

(1) You must obey the fuel safety procedures (Ref. AMM TASK 28-10-00-910-001) when you do work in a fuel tank.
(2) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.

Subtask 28-12-44-650-066-A ** ON A/C NOT FOR ALL

B. Fuel Configuration (ACT1 Installed)
(1) Defuel ACT1 (Ref. AMM TASK 28-25-00-650-001).
(2) Drain the remaining fuel from the ACT (Ref. AMM TASK 28-25-00-650-005).

Subtask 28-12-44-650-067-A ** ON A/C NOT FOR ALL

C. Fuel Configuration (ACT1 and ACT2 Installed)
(1) Defuel the applicable ACT (Ref. AMM TASK 28-25-00-650-001).
(2) Drain the remaining fuel from the applicable ACT (Ref. AMM TASK 28-25-00-650-005).

Subtask 28-12-44-865-050-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	ACT1/REFUEL & SPLY	33QU	L29
121VU	ACT XFR VALVE MAN CTL	30QH	N29
121VU	ACT1/CTL & SPLY	9QH	P29
121VU	ACT PUMP SUPPLY	25QH	Q29
** ON A/C NOT FOR ALL
121VU	ACT2/REFUEL & SPLY	34QU	L28
121VU	ACT2/CTL & SPLY	10QH	P28

Subtask 28-12-44-010-060-A ** ON A/C NOT FOR ALL

E. Get Access (ACT1 Installed)
(1) Put an ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the aft cargo-compartment-door 826.
(2) Open the aft cargo-compartment door to get access to ACT1.
(3) Remove the manhole cover from the rear wall of ACT1 (Ref. AMM TASK 28-11-37-000-001), (Ref. AMM TASK 28-10-00-910-002).

Subtask 28-12-44-010-061-A ** ON A/C NOT FOR ALL

F. Get Access (ACT1 and ACT2 Installed)
(1) Put an ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the aft cargo-compartment-door 826.
(2) Open the aft cargo-compartment door to get access to the ACTs.
(3) To remove check valve 173QM1 from ACT1:
(a) Remove ACT2 (Ref. AMM TASK 28-11-27-000-001) for access to the manhole cover on the rear wall of ACT1.
(b) Remove the manhole cover from the rear wall of ACT1 (Ref. AMM TASK 28-11-37-000-001), (Ref. AMM TASK 28-10-00-910-002).
(4) To remove check valve 173QM2 from ACT2:
(a) Remove the manhole cover from the rear wall of ACT2 (Ref. AMM TASK 28-11-37-000-001), (Ref. AMM TASK 28-10-00-910-002).

4. Procedure
Subtask 28-12-44-020-055-A ** ON A/C NOT FOR ALL

A. Removal of Check Valve 173QM1

Check Valve 173QM1 ** ON A/C NOT FOR ALL

(1) Loosen the clamp (2) and move it along the pipe (1) away from the check valve (3).
(2) Remove the check valve (3) from the pipe (1) and remove the clamp (2).

Subtask 28-12-44-020-056-A ** ON A/C NOT FOR ALL

B. Removal of Check Valves 173QM1 and 173QM2

Check Valves 173QM1 and 173QM2 ** ON A/C NOT FOR ALL

(1) Loosen the clamp (2) and move it along the pipe (1) away from the check valve (3).
(2) Remove the check valve (3) from the pipe (1) and remove the clamp (2).

[Rev.10 from 2021] 2026.04.02 06:17:11 UTC