Removal of Double Check Valve

TASK 52-36-13-000-001-A
Removal of Double Check Valve

WARNING: MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

FIN: 3717GM

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)- ADJUSTABLE
No specific	AR	CAP - BLANKING
No specific	AR	CONTAINER - HYDRAULIC FLUID RESISTANT
No specific	1	FLASHLIGHT
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
151AW, 242KF, 252BG

C. Referenced Information

REFERENCE	DESIGNATION
TASK 25-55-11-000-001-A	Removal of the Aft Cargo-Compartment Partition at FR47
TASK 25-55-11-000-002-A	Removal of the Ceiling Panels in the Aft Cargo-Compartment - FR47/FR59
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 52-30-00-860-001-A	Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 53-00-00-000-801-A-01	Removal of the Floor Panels in the Cabin from FR12 to FR70 (Alternative Removal Procedure - Dry Sealing Concept)
TASK 53-00-00-000-801-A-02	Removal of the Cabin Floor Panels from FR12 to FR70 (Alternative Removal Procedure with the Skyflex Option)
Double Check Valve 3717GM

3. Job Set-up
Subtask 52-36-13-010-050-A ** ON A/C NOT FOR ALL

A. Get Access
(1) Open the AFT cargo compartment door (referred to as cargo door) and install the actuator safety locks (Ref. AMM TASK 52-30-00-860-001).
(2) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the opened cargo door.
(3) Remove the ceiling panel 151AC to get access to the double check valve at FR47 (Ref. AMM TASK 25-55-11-000-002).

Subtask 52-36-13-010-050-B ** ON A/C NOT FOR ALL

A. Get Access
(1) Open the AFT cargo compartment door (referred to as cargo door) and install the actuator safety locks (Ref. AMM TASK 52-30-00-860-001).
(2) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the opened cargo door.
(3) Remove the partition panel 151AW to get access to the double check valve at FR47 (Ref. AMM TASK 25-55-11-000-001).

NOTE: Be careful, in the space between FR47 and FR47.2 there is no light and no floor panels. Therefore use a FLASHLIGHT.

Subtask 52-36-13-010-050-C ** ON A/C NOT FOR ALL

A. Get Access
(1) Open the AFT cargo compartment door (referred to as cargo door) and install the actuator safety locks (Ref. AMM TASK 52-30-00-860-001).
(2) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the opened cargo door.
(3) Remove the ceiling panel 151EC to get access to the double check valve at FR47 (Ref. AMM TASK 25-55-11-000-002).

Subtask 52-36-13-010-050-E ** ON A/C NOT FOR ALL

A. Get Access
(1) If an additional center tank (ACT) is installed, remove floor panels 242KF and 252BG to get access to the double check valve at FR47 (Ref. AMM TASK 53-00-00-000-801).
(2) If the ACT is not installed, continue as follows:
(a) Open the AFT cargo compartment door (referred to as cargo door) and safety it with the actuator safety locks (Ref. AMM TASK 52-30-00-860-001).
(b) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the opened cargo door.
(c) Remove the partition panel 151AW to get access to the double check valve at FR47 (Ref. AMM TASK 25-55-11-000-001).

NOTE: Be careful, in the space between FR47 and FR47.2 there is no light and no floor panels. Therefore use a FLASHLIGHT.

Subtask 52-36-13-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N30
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N31
** ON A/C ALL
122VU	DOORS/CARGO	1MJ	T12
123VU	Y HYD/ELEC/PUMP	3802GX	AB06
123VU	Y HYD/ELEC/ELEC PUMP/NORM	3801GX	AB03

Subtask 52-36-13-860-051-A

C. Aircraft Maintenance Configuration
(1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
(2) Make sure that the Yellow hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
(3) Depressurize the reservoir of the Yellow hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(4) Disconnect the isolation coupling of the Power Transfer Unit (PTU) (Ref. AMM TASK 29-23-00-860-001).
(5) Put the warning notices in position to tell persons not to pressurize the Yellow hydraulic system:

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

(6) Put the CONTAINER - HYDRAULIC FLUID RESISTANT below the double check valve 3717GM to collect hydraulic fluid.

4. Procedure
Subtask 52-36-13-020-050-A

A. Removal of the Double Check Valve

CAUTION: USE A SECOND WRENCH TO APPLY COUNTERTORQUE TO THE UNION WHEN YOU DISCONNECT/CONNECT HYDRAULIC LINES ON UNIONS. IF YOU DO NOT USE THE SECOND WRENCH, THERE IS A RISK THAT YOU WILL LOOSEN OR TIGHTEN THE UNION TOO MUCH.

(1) Cut and discard the tie-wraps (4) and remove the spray cover halves (3),(5) from the hydraulic connections of the double check valve (6).
(2) Loosen the nuts and disconnect the hydraulic pipes (1),(2),(10) from the double check valve (6).
(3) Put CAP - BLANKING on the open ends of the hydraulic pipes (1),(2),(10).
(4) Remove the nut (9) and the washer (8) to disconnect the double check valve (6) from the bracket (7).
(5) Remove the double check valve (6) from the bracket (7).
(6) Put blanking caps on the open ports of the double check valve (6).

[Rev.10 from 2021] 2026.04.02 06:28:11 UTC