DOC AIRBUS | TSM A320FHigh Oil Pressure
TASK 79-33-00-810-845-A
High Oil Pressure
1. Possible Causes
A. Referenced Information
3. Fault Confirmation
Subtask 79-33-00-710-115-A ** ON A/C NOT FOR ALL
Subtask 79-33-00-860-072-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:40:46 UTC
High Oil Pressure
1. Possible Causes
- SENSOR-PRESSURE, MAIN OIL [4071KS]
- PUMP-OIL, LUBRICATION AND SCAVENGE [6004EM]
- CHECK VALVE-LUBE TRIM [4049EM]
- VARIABLE OIL FLOW REDUCTION VALVE [4069KS]
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-834-A | General Troubleshooting Guidelines for Additional Troubleshooting Information |
| TSM TASK 71-00-00-810-835-A | Component and Harness Intermittent Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults |
| AMM 71-00-00-780-802 | Test No. 13 - Main Oil Pressure Test and Adjustment |
| AMM 73-21-00-710-806 | Test No.7 - EEC Operation Test (Self Test) |
| AMM 78-36-00-010-802 | Opening of the Thrust Reverser Cowl-Doors |
| AMM 78-36-00-410-802 | Closing of the Thrust Reverser Cowl-Doors |
| AMM 79-00-00-210-810 | Visual Inspection of the Engine Oil System |
| AMM 79-21-01-000-801 | Removal of the Lubrication and Scavenge Oil Pump |
| AMM 79-21-01-400-801 | Installation of the Lubrication and Scavenge Oil Pump |
| AMM 79-21-13-000-801 | Removal of the Lube Trim Check Valve |
| AMM 79-21-13-400-801 | Installation of the Lube Trim Check Valve |
| AMM 79-21-15-000-801 | Removal of the Variable Oil Reduction Valve (VORV) |
| AMM 79-21-15-400-801 | Installation of the Variable Oil Reduction Valve (VORV) |
| AMM 79-21-18-000-801 | Removal of the Last Chance Oil Strainer |
| AMM 79-21-18-400-801 | Installation of the Last Chance Oil Strainer |
| AMM 79-33-21-000-801 | Removal of the Main Oil Pressure (MOP) Sensor |
| AMM 79-33-21-400-801 | Installation of the Main Oil Pressure (MOP) Sensor |
Subtask 79-33-00-710-115-A ** ON A/C NOT FOR ALL
A. Do the EEC system interactive test and look for maintenance messages related to the main oil pressure sensor and the low oil pressure switch. Refer to FADEC self test AMM 73-21-00-710-806.
4. Fault IsolationNOTE: The Electronic Engine Control (EEC) has detected the engine oil pressure has exceeded its high pressure advisory limit. This may indicate a problem with the oil pressure delivery system or an in range oil pressure sensor failure.
- Refer to the general troubleshooting guidelines for additional troubleshooting information (Ref. TSM TASK 71-00-00-810-834).
- Refer to the component and harness intermittent troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-835).
WARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE AND ENGINE OIL CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
WARNING:
REFER TO THE MSDS FOR ALL MATERIAL USED AND THE MANUFACTURER'S SAFETY INSTRUCTIONS FOR ALL EQUIPMENT USED. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
CAUTION:
MAKE SURE YOU REMOVE ELECTRICAL POWER FROM THE EEC BEFORE YOU REMOVE THE ELECTRICAL CONNECTORS. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE EEC CAN OCCUR.
Subtask 79-33-00-810-098-A ** ON A/C NOT FOR ALL A. Do the steps that follow:
(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) If the maintenance messages related to the main oil pressure sensor and/or the low oil pressure switch are found, do the troubleshooting for those maintenance messages.
(a) If no problems are found, return the engine to service. Monitor the engine for reoccurring maintenance message.
(b) Fix any problems that are found.
1 Do the repair confirmation, refer to the Para. 4.B.
(3) Look to see if recent maintenance was performed on the oil system which required a main oil pressure check and adjustment.
(a) If recent maintenance was performed on the oil system and the main oil pressure check and adjustment was not performed, do a check of the main oil system AMM 71-00-00-780-802.
1 Adjust the oil metering plug selection as needed to the correct the oil pressure.
2 Do the repair confirmation, refer to the Para. 4.B.
(b) If recent maintenance was not performed on the oil system which required the main oil pressure to be checked and adjusted and prior to this fault, the main oil pressure was in normal range, replace SENSOR-PRESSURE, MAIN OIL [4071KS] if not already replaced AMM 79-33-21-000-801 and AMM 79-33-21-400-801.
1 Do the main oil pressure test and adjustment procedure AMM 71-00-00-780-802.
a If the oil pressure was within the normal range and the oil metering plug did not need adjustment, do the repair confirmation, refer to the Para. 4.B.
b If the oil pressure was not within the normal range, continue with the subsequent troubleshooting steps before making an adjustment to the oil metering plug.
(4) If the fault continues after oil pressure sensor replacement, do a visual inspection of the oil tubes for damage (large dents) which can restrict the oil flow on the pressure side of the oil system AMM 79-00-00-210-810.
(a) If damage was found and was causing restricted oil flow, repair or replace as necessary.
1 Do the repair confirmation, refer to the Para. 4.B.
2 If the fault continues:
(5) Replace PUMP-OIL, LUBRICATION AND SCAVENGE [6004EM] AMM 79-21-01-000-801 and AMM 79-21-01-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(6) Replace the CHECK VALVE-LUBE TRIM [4049EM] AMM 79-21-13-000-801 and AMM 79-21-13-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(7) Inspect the last chance oil strainers for debris or obstruction AMM 79-21-18-000-801 and AMM 79-21-18-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(8) Replace VARIABLE OIL FLOW REDUCTION VALVE [4069KS] AMM 79-21-15-000-801 and AMM 79-21-15-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(9) If the fault continues or the correct oil pressure can not be obtained with an oil metering plug class change, remove the engine from service and investigate the cause of the high oil pressure.
Subtask 79-33-00-710-116-A ** ON A/C NOT FOR ALL (1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) If the maintenance messages related to the main oil pressure sensor and/or the low oil pressure switch are found, do the troubleshooting for those maintenance messages.
(a) If no problems are found, return the engine to service. Monitor the engine for reoccurring maintenance message.
(b) Fix any problems that are found.
1 Do the repair confirmation, refer to the Para. 4.B.
(3) Look to see if recent maintenance was performed on the oil system which required a main oil pressure check and adjustment.
(a) If recent maintenance was performed on the oil system and the main oil pressure check and adjustment was not performed, do a check of the main oil system AMM 71-00-00-780-802.
1 Adjust the oil metering plug selection as needed to the correct the oil pressure.
2 Do the repair confirmation, refer to the Para. 4.B.
(b) If recent maintenance was not performed on the oil system which required the main oil pressure to be checked and adjusted and prior to this fault, the main oil pressure was in normal range, replace SENSOR-PRESSURE, MAIN OIL [4071KS] if not already replaced AMM 79-33-21-000-801 and AMM 79-33-21-400-801.
1 Do the main oil pressure test and adjustment procedure AMM 71-00-00-780-802.
a If the oil pressure was within the normal range and the oil metering plug did not need adjustment, do the repair confirmation, refer to the Para. 4.B.
b If the oil pressure was not within the normal range, continue with the subsequent troubleshooting steps before making an adjustment to the oil metering plug.
(4) If the fault continues after oil pressure sensor replacement, do a visual inspection of the oil tubes for damage (large dents) which can restrict the oil flow on the pressure side of the oil system AMM 79-00-00-210-810.
(a) If damage was found and was causing restricted oil flow, repair or replace as necessary.
1 Do the repair confirmation, refer to the Para. 4.B.
2 If the fault continues:
- Go to the next step.
(5) Replace PUMP-OIL, LUBRICATION AND SCAVENGE [6004EM] AMM 79-21-01-000-801 and AMM 79-21-01-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(6) Replace the CHECK VALVE-LUBE TRIM [4049EM] AMM 79-21-13-000-801 and AMM 79-21-13-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(7) Inspect the last chance oil strainers for debris or obstruction AMM 79-21-18-000-801 and AMM 79-21-18-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(8) Replace VARIABLE OIL FLOW REDUCTION VALVE [4069KS] AMM 79-21-15-000-801 and AMM 79-21-15-400-801.
(a) Do the repair confirmation, refer to the Para. 4.B.
(9) If the fault continues or the correct oil pressure can not be obtained with an oil metering plug class change, remove the engine from service and investigate the cause of the high oil pressure.
B. Repair Confirmation
(1) Do a check of the main oil pressure AMM 71-00-00-780-802.
(a) If the main oil pressure check is OK, perform a flight cycle.
(b) If the problem does not come back on the subsequent flight, the problem has been fixed.
5. Close-up(1) Do a check of the main oil pressure AMM 71-00-00-780-802.
(a) If the main oil pressure check is OK, perform a flight cycle.
(b) If the problem does not come back on the subsequent flight, the problem has been fixed.
Subtask 79-33-00-860-072-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.