DOC AIRBUS | AMM A320FLeak Test of the APU Fuel-Line Shroud
TASK 28-22-00-790-001-A
Leak Test of the APU Fuel-Line Shroud
1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Job Set-up
Subtask 28-22-00-941-052-A
Subtask 28-22-00-790-050-A
Subtask 28-22-00-080-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.02 06:17:31 UTC
Leak Test of the APU Fuel-Line Shroud
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 | AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY |
| No specific | 1 | CAP - BLANKING |
| No specific | 1 | GAGE - REGULATOR PRESSURE, WITH SHUTOFF VALVE (1BAR TO |
| No specific | 1 | GAGE 5 BAR (75 PSI) - PRESSURE |
| No specific | AR | PLUG - BLANKING |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 28-00-00-910-001-A | Fuel Safety Procedures |
| TASK 28-22-00-710-001-A | Operational Test of the APU Fuel-Pump System on Ground to Purge the Fuel Line |
| TASK 32-12-00-010-001-A | Open the Main Gear Doors for Access |
| TASK 32-12-00-410-001-A | Close the Main Gear Doors after Access |
APU Fuel-Line Shroud - Drain Line ConnectionSubtask 28-22-00-941-052-A
A. Safety Precautions
(1) Obey the fuel safety procedures (Ref. AMM TASK 28-00-00-910-001).
(2) It is not permitted to pressurize the APU fuel-line shroud with a fluid.
Use air or nitrogen to pressurize the shroud for the leak test.
(3) Put the warning notices in position:
Subtask 28-22-00-860-050-A (1) Obey the fuel safety procedures (Ref. AMM TASK 28-00-00-910-001).
(2) It is not permitted to pressurize the APU fuel-line shroud with a fluid.
Use air or nitrogen to pressurize the shroud for the leak test.
(3) Put the warning notices in position:
- on the refuel/defuel control panel 800VU, to tell persons not to refuel the aircraft,
- on the FUEL section of the overhead panel 40VU, to tell persons not to operate the fuel system,
- on the APU section of the overhead panel 25VU, to tell persons not to operate the APU.
B. Aircraft Maintenance Configuration
(1) Open the RH main gear door (Ref. AMM TASK 32-12-00-010-001).
(2) Make sure that the APU fuel line is filled with fuel (Ref. AMM TASK 28-22-00-710-001).
Subtask 28-22-00-480-051-A ** ON A/C NOT FOR ALL (1) Open the RH main gear door (Ref. AMM TASK 32-12-00-010-001).
(2) Make sure that the APU fuel line is filled with fuel (Ref. AMM TASK 28-22-00-710-001).
C. Installation of the Test Equipment
(2) Loosen the nut (7) and disconnect the drain line (2) from the APU drain mast (6).
(4) Put a CAP - BLANKING on the disconnected line end of the APU drain mast (6).
(5) Assemble the test equipment:
(a) Connect the AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY to the GAGE 5 BAR (75 PSI) - PRESSURE and to the GAGE - REGULATOR PRESSURE, WITH SHUTOFF VALVE (1BAR TO.
(b) Make sure that the test equipment is in a good condition and that the pressure gages are approved and calibrated.
(6) Connect the test equipment to the disconnected line end of the drain line (2).
Subtask 28-22-00-480-051-B ** ON A/C NOT FOR ALL 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.
(1) On the APU drain mast, remove the bolt (5) and the washer (4) from the clamps (3) and (1). (2) Loosen the nut (7) and disconnect the drain line (2) from the APU drain mast (6).
NOTE: If you find signs of fuel leaks on the disconnected drain line, do an inspection on the APU fuel-line and do repair or do replace the applicable APU fuel-line components.
(3) Clean the component interfaces and the adjacent area.(4) Put a CAP - BLANKING on the disconnected line end of the APU drain mast (6).
(5) Assemble the test equipment:
(a) Connect the AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY to the GAGE 5 BAR (75 PSI) - PRESSURE and to the GAGE - REGULATOR PRESSURE, WITH SHUTOFF VALVE (1BAR TO.
(b) Make sure that the test equipment is in a good condition and that the pressure gages are approved and calibrated.
(6) Connect the test equipment to the disconnected line end of the drain line (2).
C. Installation of the Test Equipment
(b) Put the PLUG-BLANKING in each disconnected line end.
(2) On the APU drain mast, remove the bolt (5) and the washer (4) from the clamps (3) and (1).
(3) Loosen the nut (7) and disconnect the drain line (2) from the APU drain mast (6).
(5) Put a CAP - BLANKING on the disconnected line end of the APU drain mast (6).
(6) Assemble the test equipment:
(a) Connect the AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY to the GAGE 5 BAR (75 PSI) - PRESSURE and to the GAGE - REGULATOR PRESSURE, WITH SHUTOFF VALVE (1BAR TO.
(b) Make sure that the test equipment is in a good condition and that the pressure gages are approved and calibrated.
(7) Connect the test equipment to the disconnected line end of the drain line (2).
4. ProcedureWARNING:
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.
(1) On the right side of the Main Landing Gear (MLG) bay, disconnect the ACT cavity drain-line from the APU fuel-line shroud: NOTE: You must do this to prevent a pressurization of the cavity in the Additional Center Tank (ACT) during the test.
(a) Loosen the nuts (9) and remove the drain line elbow (10) from the T-connection (8). (b) Put the PLUG-BLANKING in each disconnected line end.
(2) On the APU drain mast, remove the bolt (5) and the washer (4) from the clamps (3) and (1).
(3) Loosen the nut (7) and disconnect the drain line (2) from the APU drain mast (6).
NOTE: If you find signs of fuel leaks on the disconnected drain line, do an inspection on the APU fuel-line and do repair or do replace the applicable APU fuel-line components.
(4) Clean the component interfaces and the adjacent area.(5) Put a CAP - BLANKING on the disconnected line end of the APU drain mast (6).
(6) Assemble the test equipment:
(a) Connect the AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY to the GAGE 5 BAR (75 PSI) - PRESSURE and to the GAGE - REGULATOR PRESSURE, WITH SHUTOFF VALVE (1BAR TO.
(b) Make sure that the test equipment is in a good condition and that the pressure gages are approved and calibrated.
(7) Connect the test equipment to the disconnected line end of the drain line (2).
Subtask 28-22-00-790-050-A
A. Leak Test of the APU Fuel-Line Shroud
(1) Do this test:
5. Close-up(1) Do this test:
| ACTION | RESULT |
|---|---|
| 1.Make sure that the shut-off valves B and C are closed and open the shut-off valve A. Start the ground air-pressure generator and slowly increase the pressure to 20 psi (1.3790 bar). |
|
| 2.Close the shut-off valve A and stop the ground air-pressure generator. |
|
| 3.Monitor the pressure gage 2 and make sure that the air pressure in the APU fuel-line shroud remains at 20 psi (1.3790 bar) for 15 minutes. |
NOTE: Leaks are not permitted. If the pressure decreases during the 15 minutes, do a leak check with the soap solution. When you find the leak(s), do the repair/replace as necessary. After the repair/replacement you must do the complete test again. |
| 4.After 15 minutes, open the shut-off valve C and release the air pressure from the APU fuel-line shroud to the ambient air. |
|
| 5.After the pressure in the APU fuel-line shroud has decreased completely, open the shut-off valve B and release the air pressure from the air supply line to the ambient air. |
|
Subtask 28-22-00-080-050-A ** ON A/C NOT FOR ALL
A. Removal of the Test Equipment
(1) On the pressure gages, make sure that the air pressure is released from the fuel-line shroud.
(2) Disconnect the test equipment from the line end of the drain line (2).
(3) Remove the blanking cap from the line end of the APU drain mast (6).
(4) Make sure that the line end connections (2) and (6) are clean and a good condition.
(5) Connect the line end of the drain line (2) to the APU drain mast (6).
(6) Put the clamps (1) and (3) in position and install the washer (4) and the bolt (5).
(7) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
Subtask 28-22-00-080-050-B ** ON A/C NOT FOR ALL (1) On the pressure gages, make sure that the air pressure is released from the fuel-line shroud.
(2) Disconnect the test equipment from the line end of the drain line (2).
(3) Remove the blanking cap from the line end of the APU drain mast (6).
(4) Make sure that the line end connections (2) and (6) are clean and a good condition.
(5) Connect the line end of the drain line (2) to the APU drain mast (6).
(6) Put the clamps (1) and (3) in position and install the washer (4) and the bolt (5).
(7) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
A. Removal of the Test Equipment
(1) On the pressure gages, make sure that the air pressure is released from the fuel-line shroud.
(2) Disconnect the test equipment from the line end of the drain line (2).
(3) Remove the blanking cap from the line end of the APU drain mast (6).
(4) Make sure that the line end connections (2) and (6) are clean and a good condition.
(5) Connect the line end of the drain line (2) to the APU drain mast (6).
(6) Put the clamps (1) and (3) in position and install the washer (4) and the bolt (5).
(7) Connect the ACT cavity drain-line to the APU fuel-line shroud:
(a) Remove the PLUG-BLANKING from each disconnected line end.
(b) Put the drain line elbow (10) in position on the T-connection (8).
(c) Tighten the nuts (9).
(8) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
Subtask 28-22-00-860-051-A (1) On the pressure gages, make sure that the air pressure is released from the fuel-line shroud.
(2) Disconnect the test equipment from the line end of the drain line (2).
(3) Remove the blanking cap from the line end of the APU drain mast (6).
(4) Make sure that the line end connections (2) and (6) are clean and a good condition.
(5) Connect the line end of the drain line (2) to the APU drain mast (6).
(6) Put the clamps (1) and (3) in position and install the washer (4) and the bolt (5).
(7) Connect the ACT cavity drain-line to the APU fuel-line shroud:
(a) Remove the PLUG-BLANKING from each disconnected line end.
(b) Put the drain line elbow (10) in position on the T-connection (8).
(c) Tighten the nuts (9).
(8) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
B. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the RH main gear door (Ref. AMM TASK 32-12-00-410-001).
(3) Remove the warning notices.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the RH main gear door (Ref. AMM TASK 32-12-00-410-001).
(3) Remove the warning notices.