Fuel-Apparent Fuel Transfer When The Crossfeed Valve Shows Closed - Wing Tank Fuel Imbalance Develops With All Pumps In Operation

TASK 28-23-00-810-803-A
Fuel-Apparent Fuel Transfer When The Crossfeed Valve Shows Closed - Wing Tank Fuel Imbalance Develops With All Pumps In Operation

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

1. Possible Causes

VALVE-FUEL CROSSFEED [10QM]
ACTUATOR-DEFUEL/TRANSFER VALVE [11QU]
VALVE-DEFUEL/TRANSFER [11QM]
VALVE-REFUEL, R WING TK [8QU]
VALVE-REFUEL, CTR TK [10QU]
VALVE-REFUEL, L WING TK [7QU]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 28-15-00-810-815-A	Unwanted Fuel Transfer (Migration) Between The Outer and Inner Cells of The Same Wing When The ECAM FUEL System Page ICTV Indications Show Correct
TSM TASK 28-23-00-810-801-A	Fuel-Crossfeed Valve Does Not Open (Close) or Opens (Closes) Slowly
TSM TASK 28-23-00-810-802-A	Fuel-Crossfeed Valve P/BSW-4QE, ON and/or OPEN legends do not come on
TSM TASK 28-23-00-810-804-A	Fuel-Crossfeed Valve status is not available or is shown incorrectly on the ECAM FUEL page
TSM TASK 28-25-00-810-810-A	Refuel Gallery - Uncommanded Fuel Transfer From One Wing To The Other Wing
AMM 28-23-00-720-001	Operational Test of Crossfeed Valve Using Individual Motors: ...
AMM 28-23-41-000-001	Removal of the Fuel Crossfeed Valve
AMM 28-23-41-400-001	Installation of the Fuel Crossfeed Valve
AMM 28-23-51-000-001	Removal of the Crossfeed Valve Actuator
AMM 28-23-51-400-001	Installation of the Crossfeed Valve Actuator
AMM 28-25-43-000-001	Removal of the Defuel/Transfer Valve
AMM 28-25-43-400-001	Installation of the Defuel/Transfer Valve
AMM 28-25-51-000-001	Removal of the Refuel Valve
AMM 28-25-51-000-002	Removal of the Refuel Valve
AMM 28-25-51-400-001	Installation of the Refuel Valve
AMM 28-25-51-400-002	Installation of the Refuel Valve
AMM 28-25-53-000-001	Removal of the Center-Tank Defuel/Transfer Valve-Actuator
AMM 28-25-53-400-001	Installation of the Center-Tank Defuel/Transfer Valve-Actuator
AMM 31-60-00-860-001	EIS Start Procedure

3. Fault Confirmation
Subtask 28-23-00-720-051-B ** ON A/C NOT FOR ALL

A. Test
(1) Do the applicable parts of the procedure for the operational test of the crossfeed valve using individual motors AMM 28-23-00-720-001 with reference to the notes that follow.

NOTE: For the fuel configuration use 2000kg(4400lb) approximately in each wing tank, and a similar amount in the center tank.
The fuel quantity is not critical but there must be sufficient ullage (space above the fuel surface) in each tank to receive fuel from the other tanks.

NOTE: Before you start the operational test make sure that the Inter-Cell Transfer Valves (ICTV) are closed and the outer cells are full.
If necessary, reset the FQIC (to close the ICTV), and operate all the pumps for twenty (20) minutes (to fill the outer cells).
The primary supply for the water scavenge/jet pump fills the outer cells.
When the outer cell fuel contents become stable, switch off the pumps.

NOTE: During the flow test with pump pressure and the crossfeed valve closed:

make sure that the cell contents are stable for twenty (20) minutes.

(2) If the crossfeed valve does not open or close, do the procedure (Ref. TSM TASK 28-23-00-810-801).
(3) If the crossfeed valve P/BSW-4QE ON and/or OPEN legends do not operate as given in the test, do the procedure (Ref. TSM TASK 28-23-00-810-802).
(4) If the crossfeed valve symbol on ECAM FUEL system display page is not shown correctly, do the procedure (Ref. TSM TASK 28-23-00-810-804).
(5) If the fuel tank contents continue to increase and decrease when the crossfeed valve is (or appears to be) closed (shut), do Para. 4.A.

NOTE: The system is pressure tested with fuel supplied from the fuel pumps. The increase and decrease in the fuel tank contents shows that fuel continues to leak through a closed (shut) crossfeed valve or another unserviceable component in the engine supply system and/or refuel gallery.

Subtask 28-23-00-720-051-D ** ON A/C NOT FOR ALL

A. Test
(1) Do the applicable parts of the procedure for the operational test of the crossfeed valve using individual motors AMM 28-23-00-720-001 with reference to the notes that follow.

NOTE: For the fuel configuration use 2000kg(4400lb) approximately in each wing tank, and 1000kg(2200lb) or less in the center tank.
The fuel quantity is not critical but there must be sufficient ullage (space above the fuel surface) in each tank to receive fuel from the other tanks.

NOTE: During the flow test with pump pressure and the crossfeed valve closed:

make sure that the tank contents are stable for twenty (20) minutes.

4. Fault Isolation
Subtask 28-23-00-810-052-D ** ON A/C NOT FOR ALL

A. Procedure
(1) If necessary, release (out) the P/BSW-4QE.
(2) Get access to the actuator, crossfeed valve (5QE) AMM 28-23-51-000-001.
(3) Do a check of the crossfeed actuator-5QE and valve-10QM installation (interface) to make sure that they are installed correctly AMM 28-23-51-400-001.
(a) Make sure that the V-clamp, that attaches the actuator to the valve, is installed correctly.
1 If necessary, re-install AMM 28-23-51-400-001.
(b) Make sure that the see/feel indicator shows closed.
1 If the see/feel indicator shows:
a Open, do the procedure (Ref. TSM TASK 28-23-00-810-801).
b Closed, do step (4).
(4) Replace the VALVE-FUEL CROSSFEED [10QM] AMM 28-23-41-000-001, and AMM 28-23-41-400-001.
(5) Do the test given in Para. 3.A.
(6) If no fault is found:

set the aircraft maintenance configuration as follows to test the DEFUEL/XFR valve with fuel pump pressure:

NOTE: When an outer cell is full the incoming fuel passes through the spill pipe into the inner cell.

(8) On the panel 800VU, put the MODE SELECT SWITCH to the OFF position.
(a) Make sure the OPEN light goes off.
(b) On the center tank rear spar, make sure the DEFUEL/XFR ACTUATOR (11QU) see/feel indicator is in the closed position.
(9) On the FUEL page, make sure the left wing inner cell fuel content and the right wing inner cell fuel content become stable and stay stable for twenty (20) minutes.
(10) If the fuel continues to flow (leaks past the valve) when the DEFUEL/XFR valve is closed.
(a) Do a check and replace if necessary:
1 The ACTUATOR-DEFUEL/TRANSFER VALVE [11QU] AMM 28-25-53-000-001, and AMM 28-25-53-400-001.
2 The VALVE-DEFUEL/TRANSFER [11QM] AMM 28-25-43-000-001, and AMM 28-25-43-400-001.
(11) Do the test given in step (6) through to step (9) again.
(12) If no fault is found:

continue with the procedure which now tests the R refuel valve with left wing fuel pumps pressure.

(13) On the panel 800VU, put the MODE SELECT SWITCH to DEFUEL/XFR position.
(a) Make sure the OPEN light comes on.
(b) On the center tank rear spar, make sure the DEFUEL/XFR ACTUATOR (11QU) see/feel indicator is in the open position.
(14) On the FUEL page, make sure the left wing inner cell fuel content decreases and the right wing inner cell fuel content increases.
(15) On the panel 800VU, put the REFUEL VALVES switch for the RIGHT wing to the NORMAL position.
(16) On the FUEL page, make sure the left wing inner cell fuel content and the right wing inner cell fuel content become stable and stay stable for twenty (20) minutes.
(17) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, R WING TK (8QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, R WING TK [8QU] AMM 28-25-51-000-001, and AMM 28-25-51-400-001.

(18) If no fault is found:

continue with the procedure which now tests the C refuel valve with left wing fuel pumps pressure.

(19) On the panel 800VU, put the REFUEL VALVES switch for the CENTER tank to the OPEN position.
(20) On the FUEL page, make sure the left wing inner cell fuel content decreases and the center tank fuel content increases.
(21) On the panel 800VU, put the REFUEL VALVES switch for the CENTER tank to the NORMAL position.
(22) On the FUEL page, make sure the left wing inner cell fuel content and the center tank fuel content become stable and stay stable for twenty (20) minutes.
(23) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, CTR TK (10QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, CTR TK [10QU] AMM 28-25-51-000-002, and AMM 28-25-51-400-002.

(24) If no fault is found:

continue with the procedure which now tests the L refuel valve with right wing fuel pumps pressure.

(25) On the panel 40VU, release (out) the L TK PUMPS P/BSWs to switch off the left wing tank fuel pumps.
(a) Make sure the OFF legends come on.
(26) On the panel 40VU, push the P/BSW-FUEL/X FEED (4QE) in to release out (CLOSED).
(a) On the FUEL page, make sure the crossfeed valve shows closed.
(b) On the center tank rear spar, make sure the ACTUATOR-FUEL CROSSFEED VALVE (5QU) see/feel indicator is in the closed position.
(27) On the panel 800VU, put the REFUEL VALVES switch for the LEFT tank to the OPEN position.
(28) On the panel 40VU, push (in) the R TK PUMPS P/BSWs.
(a) Make sure the OFF legends go off, and the FAULT legends come on momentarily.
(29) On the FUEL page, make sure the right wing inner cell fuel content decreases and the left wing inner cell fuel content increases.
(30) On the panel 800VU, put the REFUEL VALVES switch for the LEFT wing to the NORMAL position.
(31) On the FUEL page, make sure the left wing inner cell fuel content and the right wing inner cell fuel content become stable and stay stable for twenty (20) minutes.
(32) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, L WING TK (7QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, L WING TK [7QU] AMM 28-25-51-000-001, and AMM 28-25-51-400-001.

(33) If an (unexplained) fuel transfer/migration (still) continues, do the procedures:

Subtask 28-23-00-810-052-E ** ON A/C NOT FOR ALL

set the aircraft maintenance configuration as follows to test the DEFUEL/XFR valve with fuel pump pressure:

(a) If necessary, do the EIS start procedure (ECAM only) AMM 31-60-00-860-001.
(b) On the ECAM Control panel 11VU, push (in) the FUEL P/BSW.
1 Make sure the FUEL System Display page is shown on the lower ECAM Display Unit (DU).
(c) On the panel 40VU, push (in) the P/BSW-FUEL/X FEED (4QE).
1 On the FUEL page, make sure the crossfeed valve shows open.
2 On the center tank rear spar, make sure the ACTUATOR-FUEL CROSSFEED VALVE (5QU) see/feel indicator is in the open position.
(d) On panel 800VU, put the MODE SELECT SWITCH to the DEFUEL/XFR position.
1 Make sure the OPEN light comes on.
2 On the center tank rear spar, make sure the DEFUEL/XFR ACTUATOR (11QU) see/feel indicator is in the open position.
(e) On the panel 800VU, put the REFUEL VALVES switch for the RIGHT wing to the OPEN position.
(f) On the panel 40VU, push (in) the L TK PUMPS P/BSWs.
1 Make sure the OFF legends go off, and the FAULT legends come on momentarily.
(7) On the FUEL page, make sure the left wing tank fuel content decreases and the right wing tank fuel content increases.
(8) On the panel 800VU, put the MODE SELECT SWITCH to the OFF position.
(a) Make sure the OPEN light goes off.
(b) On the center tank rear spar, make sure the DEFUEL/XFR ACTUATOR (11QU) see/feel indicator is in the closed position.
(9) On the FUEL page, make sure the left wing tank fuel content and the right wing tank fuel content become stable and stay stable for twenty (20) minutes.
(10) If the fuel continues to flow (leaks past the valve) when the DEFUEL/XFR valve is closed.
(a) Do a check and replace if necessary:
1 The ACTUATOR-DEFUEL/TRANSFER VALVE [11QU] AMM 28-25-53-000-001, and AMM 28-25-53-400-001.
2 The VALVE-DEFUEL/TRANSFER [11QM] AMM 28-25-43-000-001, and AMM 28-25-43-400-001.
(11) Do the test given in Para. 4.A. Step (3) to Step (6).
(12) If no fault is found:

continue with the procedure which now tests the R refuel valve with left wing fuel pumps pressure.

(13) On the panel 800VU, put the MODE SELECT SWITCH to DEFUEL/XFR position.
(a) Make sure the OPEN light comes on.
(b) On the center tank rear spar, make sure the DEFUEL/XFR ACTUATOR (11QU) see/feel indicator is in the open position.
(14) On the FUEL page, make sure the left wing tank fuel content decreases and the right wing tank fuel content increases.
(15) On the panel 800VU, put the REFUEL VALVES switch for the RIGHT wing to the NORMAL position.
(16) On the FUEL page, make sure the left wing tank fuel content and the right wing tank fuel content become stable and stay stable for twenty (20) minutes.
(17) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, R WING TK (8QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, R WING TK [8QU] AMM 28-25-51-000-001, and AMM 28-25-51-400-001.

(18) If no fault is found:

continue with the procedure which now tests the C refuel valve with left wing fuel pumps pressure.

(19) On the panel 800VU, put the REFUEL VALVES switch for the CENTER tank to the OPEN position.
(20) On the FUEL page, make sure the left wing tank fuel content decreases and the center tank fuel content increases.
(21) On the panel 800VU, put the REFUEL VALVES switch for the CENTER tank to the NORMAL position.
(22) On the FUEL page, make sure the left wing tank fuel content and the center tank fuel content become stable and stay stable for twenty (20) minutes.
(23) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, CTR TK (10QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, CTR TK [10QU] AMM 28-25-51-000-002, and AMM 28-25-51-400-002.

(24) If no fault is found:

continue with the procedure which now tests the L refuel valve with right wing fuel pumps pressure.

(25) On the panel 40VU, release (out) the L TK PUMPS P/BSWs to switch off the left wing tank fuel pumps.
(a) Make sure the OFF legends come on.
(26) On the panel 40VU, release (out) the P/BSW-FUEL/X FEED (4QE).
(a) On the FUEL page, make sure the crossfeed valve shows closed.
(b) On the center tank rear spar, make sure the ACTUATOR-FUEL CROSSFEED VALVE (5QU) see/feel indicator is in the closed position.
(27) On the panel 800VU, put the REFUEL VALVES switch for the LEFT tank to the OPEN position.
(28) On the panel 40VU, push (in) the R TK PUMPS P/BSWs.
(a) Make sure the OFF legends go off, and the FAULT legends come on momentarily.
(29) On the FUEL page, make sure the right wing tank fuel content decreases and the left wing tank fuel content increases.
(30) On the panel 800VU, put the REFUEL VALVES switch for the LEFT wing to the NORMAL position.
(31) On the FUEL page, make sure the left wing tank fuel content and the right wing tank fuel content become stable and stay stable for twenty (20) minutes.
(32) If the fuel continues to flow (leaks past the valve) when the VALVE-REFUEL, L WING TK (7QU) is closed, do a check and replace if necessary:

the VALVE-REFUEL, L WING TK [7QU] AMM 28-25-51-000-001, and AMM 28-25-51-400-001.

[Rev.8 from Aug 2018] 2026.04.04 04:28:40 UTC