DOC AIRBUS | AMM A320FLeak Check of the Pb Sense Line [IAE]
TASK 73-22-49-790-010-A
Leak Check of the Pb Sense Line
1. Reason for the Job
This procedure outlines how to check for leaks in the Pb sense lines
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 73-22-49-941-051-A ** ON A/C NOT FOR ALL
Subtask 73-22-49-020-053-A ** ON A/C NOT FOR ALL
Subtask 73-22-49-410-051-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 03:01:09 UTC
Leak Check of the Pb Sense Line
1. Reason for the Job
This procedure outlines how to check for leaks in the Pb sense lines
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | NITROGEN COMPRESSED SOURCE 5 BAR (72.5 PSI) - (DRY) |
| No specific | 1 | PLUG - BLANKING (AS15829 TYPE) |
| No specific | 1 | PLUG - BLANKING, PRESSURE |
| No specific | AR | WARNING NOTICE(S) |
| No specific | Torque wrench: range to between 44 and 36 lbf.in (0.50 and 0.41 m.daN )  | |
| No specific | Torque wrench: range to between 45 and 36 lbf.in (0.51 and 0.41 m.daN ) | |
| No specific | Torque wrench: range to between 150 and 142 lbf.in (1.70 and 1.60 m.daN ) | |
| No specific | Torque wrench: range to between 177 and 159 lbf.in (2.00 and 1.80 m.daN ) | |
| No specific | Torque wrench: range to between 310 and 283 lbf.in (3.50 and 3.20 m.daN ) | |
| IAE1R19786 | 1 | CONNECTOR |
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.V02-126) | lockwire |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 70-23-11-911-013-A | General Torque Tightening Techniques |
| TASK 71-13-00-010-010-A | Opening of the Fan Cowls 437AL(447AL),438AR(448AR) |
| TASK 71-13-00-410-010-A | Closing of the Fan Cowls 437AL(447AL),438AR(448AR) |
PB Sense LineSubtask 73-22-49-941-051-A ** ON A/C NOT FOR ALL
A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize FADEC 1(2).
Subtask 73-22-49-010-051-A ** ON A/C NOT FOR ALL (1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize FADEC 1(2).
B. Get Access
(1) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR.
4. Procedure(1) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR.
Subtask 73-22-49-020-053-A ** ON A/C NOT FOR ALL
A. Remove the Pb sense line pipe
(1) Remove and discard the lockwire from the connectors.
(2) Disconnect the connector nut (1) from the P3/T3 sensor.
(3) Disconnect the connector nut (3) from the tube (2).
For Pre SB 75-0081
(4) Remove the bolt (7) and the washer (6) from the clip point 5433.
For Post SB 75-0081
(5) Remove the nut (12), the bolt (8) and the spacer (10) from the clip point 6108.
End of SB 75-0081.
(6) Remove the nut (14), bolt (19), washer (18) and spacer (15) from the clip point 6066.
(7) Remove the pipe (2).
Subtask 73-22-49-020-057-A ** ON A/C NOT FOR ALL (1) Remove and discard the lockwire from the connectors.
(2) Disconnect the connector nut (1) from the P3/T3 sensor.
(3) Disconnect the connector nut (3) from the tube (2).
For Pre SB 75-0081
(4) Remove the bolt (7) and the washer (6) from the clip point 5433.
For Post SB 75-0081
(5) Remove the nut (12), the bolt (8) and the spacer (10) from the clip point 6108.
End of SB 75-0081.
(6) Remove the nut (14), bolt (19), washer (18) and spacer (15) from the clip point 6066.
(7) Remove the pipe (2).
B. Disconnect the Tube at the Electronic Engine Control (EEC)
(1) Remove the lockwire from the tube nut.
(2) Disconnect the tube at the EEC unit.
(3) Put a PLUG - BLANKING, PRESSURE in the tube to prevent air leakage. No air leakage is permitted.
Subtask 73-22-49-420-052-A ** ON A/C NOT FOR ALL (1) Remove the lockwire from the tube nut.
(2) Disconnect the tube at the EEC unit.
(3) Put a PLUG - BLANKING, PRESSURE in the tube to prevent air leakage. No air leakage is permitted.
C. Preparation for the pressure test
(1) Install the IAE1R19786 CONNECTOR to the pipe (4).
(2) Connect the nitrogen supply to the connector.
PRE SBE 73-0198
(3) Blank off the vented traps.
(a) Blank off the vented traps using clips and bolts as shown in figure.
(b) TORQUE the nut (6) to between 44 and 36 lbf.in (0.50 and 0.41 m.daN ).
END OF PRE SBE 73-0198
POST SBE 73-0198
(4) Install the blanking plug.
(a) Remove the vented plug assembly and install the PLUG - BLANKING (AS15829 TYPE).
(b) TORQUE the blanking plug to between 310 and 283 lbf.in (3.50 and 3.20 m.daN ).
END OF POST SBE 73-0198
(5) Coat the sense line joints, including the flexible tube that connects to the EEC, with snoop leak detection fluid.
Subtask 73-22-49-720-050-A ** ON A/C NOT FOR ALL (1) Install the IAE1R19786 CONNECTOR to the pipe (4).
(2) Connect the nitrogen supply to the connector.
PRE SBE 73-0198
(3) Blank off the vented traps.
(a) Blank off the vented traps using clips and bolts as shown in figure.
(b) TORQUE the nut (6) to between 44 and 36 lbf.in (0.50 and 0.41 m.daN )
. END OF PRE SBE 73-0198
POST SBE 73-0198
(4) Install the blanking plug.
(a) Remove the vented plug assembly and install the PLUG - BLANKING (AS15829 TYPE).
(b) TORQUE the blanking plug to between 310 and 283 lbf.in (3.50 and 3.20 m.daN )
. END OF POST SBE 73-0198
(5) Coat the sense line joints, including the flexible tube that connects to the EEC, with snoop leak detection fluid.
NOTE: Make sure that the upper flexible section of the sense line is coated on the flexible portion and the unions.
D. Test
(2) Continue to pressurize the sense lines for two minutes.
(4) Release the pressure from the sense line.
(5) Check the security of the unions or any leaking joints. Torque the connector to the recommended range (Ref. AMM TASK 70-23-11-911-013).
(6) If connectors are found under-tightened, torque to the recommended range and repeat the leak check.
(7) If a leak is found in the flexible line or on a rigid tube, replace the defective parts and repeat the leak check.
(8) If a joint continues to leak, replace the tubes both sides of the leaking joint and inform IAE Technical Services stating the location.
(10) Remove the nitrogen supply and the connector IAE1R19786 from the tube (4).
PRE SBE 73-0198
(11) Loosen the nut (6) and remove the bolts and the blanking clips from the vented traps.
END OF PRE SBE 73-0198
POST SBE 73-0198
(12) Remove the blanking plug (AS15829) and install the vented plug assembly. TORQUE the vented plug assembly to between 310 and 283 lbf.in (3.50 and 3.20 m.daN ).
END OF POST SBE 73-0198
Subtask 73-22-49-420-053-A ** ON A/C NOT FOR ALL CAUTION:
DO NOT BLOW AIR OR NITROGEN GAS THROUGH THE SENSING LINES TO THE ELECTRONIC ENGINE CONTROL UNIT (EEC). UNWANTED MATERIALS CAN CAUSE CONTAMINATION AND DAMAGE TO THE EEC.
(1) Carefully open the regulator valve of the NITROGEN COMPRESSED SOURCE 5 BAR (72.5 PSI) - (DRY) and gradually increase the pressure to 75 psi and check for leaks. (2) Continue to pressurize the sense lines for two minutes.
NOTE: If necessary, re-apply snoop leak detection fluid to confirm a leak.
(3) If a leak is detected, identify the leaking joint/s. If possible photograph the joint and the tube clipping arrangement both sides of the joint. (4) Release the pressure from the sense line.
(5) Check the security of the unions or any leaking joints. Torque the connector to the recommended range (Ref. AMM TASK 70-23-11-911-013).
(6) If connectors are found under-tightened, torque to the recommended range and repeat the leak check.
(7) If a leak is found in the flexible line or on a rigid tube, replace the defective parts and repeat the leak check.
(8) If a joint continues to leak, replace the tubes both sides of the leaking joint and inform IAE Technical Services stating the location.
NOTE: If replacement parts are not available before the aircraft returns to service, arrange for their replacement at the next convenient point when spare parts become available.
(9) Clean the snoop leak detection fluid from the tubes. (10) Remove the nitrogen supply and the connector IAE1R19786 from the tube (4).
PRE SBE 73-0198
(11) Loosen the nut (6) and remove the bolts and the blanking clips from the vented traps.
END OF PRE SBE 73-0198
POST SBE 73-0198
(12) Remove the blanking plug (AS15829) and install the vented plug assembly. TORQUE the vented plug assembly to between 310 and 283 lbf.in (3.50 and 3.20 m.daN )
. END OF POST SBE 73-0198
E. Install the Pb sense line tube
(1) Connect the tube (2) to the P3/T3 sensor and to the tube (4) (do not tighten at this point).
Pre SB 75-0081
(2) Install the clip 5433, the bolt (7) and the washer (6).
(3) TORQUE the bolt (7) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN ).
Post SB 75-0081
(4) Install the clip 6108, the bolt (8), the spacer (10) and the nut (12).
(5) TORQUE the bolt (8) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN ).
End of SB 75-0081.
(6) Install the clip 6066, the bolt (19), the washer (18), the spacer (15) and the nut (14).
(7) TORQUE the bolt (19) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN ).
(8) TORQUE the tube connectors (1) and (3) to between 177 and 159 lbf.in (2.00 and 1.80 m.daN ).
(9) Safety the tube connectors with corrosion resistant steel lockwire.
Subtask 73-22-49-420-056-A ** ON A/C NOT FOR ALL (1) Connect the tube (2) to the P3/T3 sensor and to the tube (4) (do not tighten at this point).
Pre SB 75-0081
(2) Install the clip 5433, the bolt (7) and the washer (6).
(3) TORQUE the bolt (7) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN )
. Post SB 75-0081
(4) Install the clip 6108, the bolt (8), the spacer (10) and the nut (12).
(5) TORQUE the bolt (8) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN )
. End of SB 75-0081.
(6) Install the clip 6066, the bolt (19), the washer (18), the spacer (15) and the nut (14).
(7) TORQUE the bolt (19) to between 45 and 36 lbf.in (0.51 and 0.41 m.daN )
. (8) TORQUE the tube connectors (1) and (3) to between 177 and 159 lbf.in (2.00 and 1.80 m.daN )
. (9) Safety the tube connectors with corrosion resistant steel lockwire.
F. Install the Tube at the Electronic Engine Control (EEC)
(1) Remove the PLUG - BLANKING, PRESSURE from the tube and connect the tube to the EEC.
(2) TORQUE the tube connector to between 150 and 142 lbf.in (1.70 and 1.60 m.daN ) (Ref. AMM TASK 70-23-11-911-013).
(3) Safety the tube connector with lockwire (Material No.V02-126) .
5. Close-up(1) Remove the PLUG - BLANKING, PRESSURE from the tube and connect the tube to the EEC.
(2) TORQUE the tube connector to between 150 and 142 lbf.in (1.70 and 1.60 m.daN )
(Ref. AMM TASK 70-23-11-911-013). (3) Safety the tube connector with lockwire (Material No.V02-126) .
Subtask 73-22-49-410-051-A ** ON A/C NOT FOR ALL