DOC AIRBUS | AMM A320FInspection of the Oil System [IAE]
TASK 79-00-00-200-010-A
Inspection of the Oil System
This TASK gives instruction to check the condition of the oil system via engine oil analysis, Magnetic Chip Detectors (MCDs) and oil filters.
2. Job Set-up Information
A. Work Zones and Access Panels
B. Referenced Information
3. Job Set-up
Subtask 79-00-00-869-053-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 03:39:56 UTC
Inspection of the Oil System
ZONE: 400
1. Reason for the JobThis TASK gives instruction to check the condition of the oil system via engine oil analysis, Magnetic Chip Detectors (MCDs) and oil filters.
2. Job Set-up Information
A. Work Zones and Access Panels
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 400 | POWER PLANT, NACELLES AND PYLONS |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 12-13-79-610-010-A | Drain the Engine Oil System |
| TASK 12-13-79-610-011-A | Check Oil Level and Replenish |
| TASK 12-13-79-610-012-A | Prime the Engine Oil System |
| TASK 12-32-79-600-010-A | Sampling of the Engine Oil for Analysis |
| TASK 29-11-51-000-010-A | Removal of the Engine Pump |
| TASK 29-11-51-400-010-A | Installation of the Engine Pump |
| TASK 71-00-00-710-043-A | Normal Engine Automatic-Start Procedure |
| TASK 71-00-00-710-047-A | Normal Engine Manual-Start Procedure |
| TASK 71-73-49-200-010-A | Inspection of the Oil, Hydraulic and Water Drain Tubes |
| TASK 72-50-50-100-010-B | Cleaning of No. 5 Bearing Oil Service Lines, Filter and Oil Jet |
| TASK 72-60-23-000-010-A | Removal of the Hydraulic Pump Drive Seal Assembly and Mating Ring |
| TASK 72-60-23-400-010-A | Installation of the Hydraulic Pump Drive Seal Assembly Mating Ring |
| TASK 75-22-00-200-010-A | General Visual Inspection of the No 4 Bearing Cooling Air Tubes for Damage and Security and of the No 4 Bearing Cooler and Associated Inlet in the Left ... |
| TASK 79-00-00-200-011-A | Inspection of the Magnetic Chip Detectors for Debris |
| TASK 79-00-00-200-012-A | Inspection of the Oil Filters |
| TASK 79-00-00-200-013-A | Check Master Magnetic Chip Detector for Evidence of Metallic Debris |
| TASK 79-20-00-200-010-A | General Visual Inspection of the Oil Distribution System Components, Tubes and Joints |
| TASK 79-21-44-000-010-A | Removal of the Pressure Oil Filter Element |
| TASK 79-21-44-400-010-A | Installation of the Pressure Oil Filter Element |
| TASK 79-22-44-000-010-A | Removal of the Scavenge Oil Filter Element |
| TASK 79-22-44-400-010-A | Installation of the Scavenge Oil Filter Element |
Oil Condition DiagnosticsSubtask 79-00-00-869-053-A ** ON A/C NOT FOR ALL
A. Not Applicable
4. ProcedureNOTE: Read this entire procedure before proceeding.
Subtask 79-00-00-210-064-A ** ON A/C NOT FOR ALL A. Examine the Magnetic Chip Detectors (MCDs)
(1) Examine the magnetic chip detectors (MMCD and MCDs) for debris (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011).
(2) Check the oil filters for contamination (Ref. AMM TASK 79-00-00-200-012).
Subtask 79-00-00-210-075-A ** ON A/C NOT FOR ALL (1) Examine the magnetic chip detectors (MMCD and MCDs) for debris (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011).
(2) Check the oil filters for contamination (Ref. AMM TASK 79-00-00-200-012).
NOTE: If any metallic debris is found, perform fault isolation (follow task AMM instructions).
B. Examine the Condition of the Engine Oil
(1) Visual inspection of oil:
(b) Check oil filters and MCDs for contamination (Ref. AMM TASK 79-00-00-200-012), (Ref. AMM TASK 79-00-00-200-011) and (Ref. AMM TASK 79-00-00-200-013) (if not previously done in subtask 79-00-00-210-064). If any metallic debris is found in the filters, perform fault isolation (follow AMM task instructions).
(c) (2) Chemical and physical testing of the oil
(a) TAN - TAN is an acronym for "total acid number" and gives an indication if oil has been exposed to elevated temperature.
(b) Kinematic Viscosity - A measure of oil resistance to flow. Oil must be within a certain range to do its job properly.
(c) Hydraulic fluid - Whether introduced accidentally into the oil system or by way of a hydraulic pump leak, it can have a significant negative impact on viscosity.
(d) Water contamination - Elevated water contamination in the oil can result in corrosion of certain alloys leading to harmful deposits.
(a) Obtain an oil sample for analysis (Ref. AMM TASK 12-32-79-600-010). A sample of 8 oz (0.23 kg) should be sufficient.
1 Examine No.4 bearing air cooler (ACAC) and tubes for blockage/damage (Ref. AMM TASK 75-22-00-200-010)
2 Examine the Air Cooled Oil Cooler (ACOC) for cracks, leaks, duct blockage or loose connections (Ref. AMM TASK 79-20-00-200-010).
3 4 Check No.4 bearing compartment scavenge valve (Ref. AMM TASK 79-20-00-200-010), including HPC stage 10 make-up air connections at scavenge valve.
5 Examine Fuel Cooled Oil Cooler (FCOC) for leaks (Ref. AMM TASK 79-20-00-200-010).
6 After oil sample is taken, double flush oil system per step B.(5).
(4) Submit oil sample for the following testing:
(a) Total Acidity Number (TAN) given as mg KOH /g. TAN limit is no more than 2.0 mg KOH/g.
(b) Kinematic viscosity. Limits are +25 percent/-10 percent compared to new oil of same brand, type and weight. See inspection method at 104 deg.F (40.00 deg.C), ASTM D445/MIL PRF-23669.
(c) Hydraulic fluid contamination. Limit contamination is less than or equal to 0.1 percent (Ref. ASTM- D1091).
(d) Water contamination. Limit contamination is less than 1000 ppm water (Ref. Karl Fisher test, ASTMD-6304-04ae1).
(5) Double flush the oil system as follows:
(a) Completely drain the oil system (Ref. AMM TASK 12-13-79-610-010).
(b) Check oil filters for contamination (Ref. AMM TASK 79-00-00-200-012) and disposition any findings (follow task AMM instructions).
(c) Clean or replace the pressure filter (Ref. AMM TASK 79-21-44-000-010), (Ref. AMM TASK 79-21-44-400-010) and (Ref. AMM TASK 79-00-00-200-012).
(d) Replace the scavenge filter (Ref. AMM TASK 79-22-44-000-010) and (Ref. AMM TASK 79-22-44-400-010).
(e) Clean any viscous deposits from the filter housing and ports.
(f) Examine the MCDs (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011) and disposition any findings (follow task AMM instructions). Clean off the MCDs and re-install.
(g) Fill the oil system with the new engine oil (Ref. AMM TASK 12-13-79-610-010), (Ref. AMM TASK 12-13-79-610-011) and (Ref. AMM TASK 12-13-79-610-012).
(i) Completely drain the oil system (Ref. AMM TASK 12-13-79-610-010).
(j) Inspect the MCDs and disposition any findings (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011). Clean the MCDs and re-install.
1 Inspect the pressure filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012).
2 Inspect the scavenge filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012).
(m) Inspect the scavenge and pressure filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012). If actionable findings are present, repeat double flush per 4.B.(5)(a) to 4.B.(5)(m). If no actionable findings, reinstall filters and continue to 4.B.(5)(n).
(n) Inspect the (MCDs) and disposition any findings (Ref. AMM TASK 79-00-00-200-013), (Ref. AMM TASK 79-00-00-200-011). If actionable findings are present, repeat double flush per step 4.B.(5)(b) to 4.B.(5)(m). If no actionable findings, re-install MCDs and continue to step 4.B.(5)(o).
(o) Fill the oil system to a maximum level within 30 minutes of engine shutdown.
(6) Oil sample laboratory results
(b) If TAN exceeds limit:
1 Examine No.5 bearing compartment and oil service tubes (Ref. AMM TASK 72-50-50-100-010)).
2 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
1 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
1 Examine the hydraulic pump drain pad line for blockage and clean if necessary (Ref. AMM TASK 71-73-49-200-010). Check for hydraulic fluid leakage. If not present, continue to 4.B.(6)(d).3_.
2 Remove/Replace the hydraulic pump (Ref. AMM TASK 29-11-51-000-010) and (Ref. AMM TASK 29-11-51-400-010) and hydraulic pump drive gear shaft seal (Ref. AMM TASK 72-60-23-000-010) and (Ref. AMM TASK 72-60-23-400-010), NMSB 72-0288.
3 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
1 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
(1) Visual inspection of oil:
NOTE: The color of new oil can be different between oil brands. Some oil brands are dark when delivered as new. In general, the oil color will get darker with engine operation. If oil appears opaque (non-transparent), it may be a sign that suspended carbon particles are present in the oil. This is not cause for rejection.
(a) Does oil appear to be thicker or thinner (viscosity) than new oil (of same brand or type)? This could be a sign of oil contamination by hydraulic fluid or fuel or excessive heat causing physical property changes in the oil. (b) Check oil filters and MCDs for contamination (Ref. AMM TASK 79-00-00-200-012), (Ref. AMM TASK 79-00-00-200-011) and (Ref. AMM TASK 79-00-00-200-013) (if not previously done in subtask 79-00-00-210-064). If any metallic debris is found in the filters, perform fault isolation (follow AMM task instructions).
(c) (2) Chemical and physical testing of the oil
(a) TAN - TAN is an acronym for "total acid number" and gives an indication if oil has been exposed to elevated temperature.
(b) Kinematic Viscosity - A measure of oil resistance to flow. Oil must be within a certain range to do its job properly.
(c) Hydraulic fluid - Whether introduced accidentally into the oil system or by way of a hydraulic pump leak, it can have a significant negative impact on viscosity.
(d) Water contamination - Elevated water contamination in the oil can result in corrosion of certain alloys leading to harmful deposits.
WARNING:
DO NOT REMOVE THE FILLER CAP OF THE OIL TANK IMMEDIATELY AFTER ENGINE OPERATION. LET THE OIL PRESSURE DECREASE FOR A MINIMUM OF 5 MINUTES AFTER THE ENGINE SHUTDOWN. IF YOU OPEN THE FILLER CAP WHEN THERE IS PRESSURE IN THE TANK, THE OIL CAN BURN YOU DANGEROUSLY.
(3) Taking an oil sample(a) Obtain an oil sample for analysis (Ref. AMM TASK 12-32-79-600-010). A sample of 8 oz (0.23 kg) should be sufficient.
NOTE: Oil sample should be taken within 12 flight hours of initial observation of unusual oil condition, provided no oil system fault indications (Electronic Centralized Aircraft Monitoring-ECAM) are displayed. If oil system-related ECAM message is displayed, follow related AMM/TSM instructions before proceeding with this task.
NOTE: It is recommended that an equal quantity of new (unused) oil of same brand or type also be submitted to allow for direct comparison to aid with interpretation of results.
(b) When the oil sample is taken, also perform the following:1 Examine No.4 bearing air cooler (ACAC) and tubes for blockage/damage (Ref. AMM TASK 75-22-00-200-010)
2 Examine the Air Cooled Oil Cooler (ACOC) for cracks, leaks, duct blockage or loose connections (Ref. AMM TASK 79-20-00-200-010).
3 4 Check No.4 bearing compartment scavenge valve (Ref. AMM TASK 79-20-00-200-010), including HPC stage 10 make-up air connections at scavenge valve.
5 Examine Fuel Cooled Oil Cooler (FCOC) for leaks (Ref. AMM TASK 79-20-00-200-010).
6 After oil sample is taken, double flush oil system per step B.(5).
(4) Submit oil sample for the following testing:
(a) Total Acidity Number (TAN) given as mg KOH /g. TAN limit is no more than 2.0 mg KOH/g.
(b) Kinematic viscosity. Limits are +25 percent/-10 percent compared to new oil of same brand, type and weight. See inspection method at 104 deg.F (40.00 deg.C), ASTM D445/MIL PRF-23669.
(c) Hydraulic fluid contamination. Limit contamination is less than or equal to 0.1 percent (Ref. ASTM- D1091).
(d) Water contamination. Limit contamination is less than 1000 ppm water (Ref. Karl Fisher test, ASTMD-6304-04ae1).
(5) Double flush the oil system as follows:
(a) Completely drain the oil system (Ref. AMM TASK 12-13-79-610-010).
(b) Check oil filters for contamination (Ref. AMM TASK 79-00-00-200-012) and disposition any findings (follow task AMM instructions).
(c) Clean or replace the pressure filter (Ref. AMM TASK 79-21-44-000-010), (Ref. AMM TASK 79-21-44-400-010) and (Ref. AMM TASK 79-00-00-200-012).
(d) Replace the scavenge filter (Ref. AMM TASK 79-22-44-000-010) and (Ref. AMM TASK 79-22-44-400-010).
(e) Clean any viscous deposits from the filter housing and ports.
(f) Examine the MCDs (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011) and disposition any findings (follow task AMM instructions). Clean off the MCDs and re-install.
(g) Fill the oil system with the new engine oil (Ref. AMM TASK 12-13-79-610-010), (Ref. AMM TASK 12-13-79-610-011) and (Ref. AMM TASK 12-13-79-610-012).
NOTE: A half-full tank is sufficient enough to flush the oil system, use approximately 20 US quarts of oil.
(h) Operate the engine at ground idle for 10 minutes (Ref. AMM TASK 71-00-00-710-043), (Ref. AMM TASK 71-00-00-710-047).(i) Completely drain the oil system (Ref. AMM TASK 12-13-79-610-010).
(j) Inspect the MCDs and disposition any findings (Ref. AMM TASK 79-00-00-200-013) and (Ref. AMM TASK 79-00-00-200-011). Clean the MCDs and re-install.
1 Inspect the pressure filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012).
2 Inspect the scavenge filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012).
NOTE: If any metallic debris is found on the MCDs or oil filters, perform fault isolation (follow task AMM instructions).
(k) Fill the oil system with new engine oil (Ref. AMM TASK 12-13-79-610-010), (Ref. AMM TASK 12-13-79-610-011) and (Ref. AMM TASK 12-13-79-610-012).CAUTION:
DO NOT DRY-MOTOR THE ENGINE. RUN THE ENGINE TO GET CORRECT OIL LEVEL INDICATIONS. IF YOU DO NOT OBEY THESE INSTRUCTIONS, OVER-SERVICING CAN OCCUR.
(l) Do an engine ground idle oil system leak check (Ref. AMM TASK 71-00-00-710-043) and (Ref. AMM TASK 71-00-00-710-047).(m) Inspect the scavenge and pressure filter and disposition any findings (Ref. AMM TASK 79-00-00-200-012). If actionable findings are present, repeat double flush per 4.B.(5)(a) to 4.B.(5)(m). If no actionable findings, reinstall filters and continue to 4.B.(5)(n).
(n) Inspect the (MCDs) and disposition any findings (Ref. AMM TASK 79-00-00-200-013), (Ref. AMM TASK 79-00-00-200-011). If actionable findings are present, repeat double flush per step 4.B.(5)(b) to 4.B.(5)(m). If no actionable findings, re-install MCDs and continue to step 4.B.(5)(o).
(o) Fill the oil system to a maximum level within 30 minutes of engine shutdown.
(6) Oil sample laboratory results
NOTE: It is recommended that a maximum fly-on of 24 flight hours be observed while waiting for oil sample results, provided no oil system fault indications (ECAM) are displayed. If oil system-related ECAM message is displayed follow related AMM/TSM instructions before proceeding with this task.
(a) If the results from all 4 of the oil tests are within limits, the engine may continue in service with re-oil sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.(b) If TAN exceeds limit:
1 Examine No.5 bearing compartment and oil service tubes (Ref. AMM TASK 72-50-50-100-010)).
2 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
- If repeat analysis still shows TAN above limit, remove engine for shop visit.
- If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
1 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
- If repeat analysis still shows viscosity out of limits, remove engine for shop visit.
- If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
1 Examine the hydraulic pump drain pad line for blockage and clean if necessary (Ref. AMM TASK 71-73-49-200-010). Check for hydraulic fluid leakage. If not present, continue to 4.B.(6)(d).3_.
2 Remove/Replace the hydraulic pump (Ref. AMM TASK 29-11-51-000-010) and (Ref. AMM TASK 29-11-51-400-010) and hydraulic pump drive gear shaft seal (Ref. AMM TASK 72-60-23-000-010) and (Ref. AMM TASK 72-60-23-400-010), NMSB 72-0288.
3 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
- If repeat analysis still shows hydraulic fluid contamination above limit, remove engine for shop visit.
- If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
1 Repeat oil sample per step 4.B.(3)(a) and tests per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
a If all results are within limits, perform sample per step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
b If results are not within limits, double flush per step 4.B.(5) and repeat sample per step 4.B.(3)(a) and analysis per step 4.B.(4) and step 4.B.(6) within 50-75 hours flight time.
- If repeat analysis still shows water contamination above limit, remove engine for shop visit.
- If all results are within limits, perform sample step 4.B.(3)(a) and analysis again per step 4.B.(4) and step 4.B.(6) after 600 flight hour interval.
NOTE: