W DOC AIRBUS | TSM A320F

Fumes in the Cabin/Oil Smoke at the APU Exhaust (131-9(A))

TASK 49-00-81-810-874-A
Fumes in the Cabin/Oil Smoke at the APU Exhaust (131-9(A))

1. Possible Causes
  • plumbing/tubing
  • APU component interfaces
  • OIL COOLER
  • OIL PUMP ASSY
  • GEN-APU [8XS]
  • FUEL CONTROL UNIT P19
  • INLET GUIDE-VANE ACTUATOR P21
  • oil contamination inside cooling-fan discharge duct
  • unwanted material on the surfaces of the air intake system components
  • the oil level in the oil reservoir is above the FULL mark on the oil sight glas
  • APU [4005KM]
  • OIL COOLER (8079KM)
  • OIL PUMP ASSY (8080KM)
  • FUEL CONTROL UNIT (8022KM)
  • INLET GUIDE-VANE ACTUATOR (8014KM)
  • flexible seals on the air intake system
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
LIGHT SOURCE - ULTRA-VIOLET
 B. Consumable Materials
REFERENCE
DESIGNATION
No specific
overflow drain tool
 C. Referenced Information
REFERENCE
DESIGNATION
AMM 12-33-21-618-001
Pre-conditioning through the LP Ground Connection
AMM 21-00-00-100-001
Cleaning of Special Components in the Environmental Control System (ECS)
AMM 21-00-00-615-001
Decontamination of the Environmental Control System (ECS) when the Temperature is below 24 deg.C (APU)
AMM 21-00-00-615-002
Decontamination of the Environmental Control System (ECS) when the Temperature is above 24 deg.C (APU)
AMM 24-23-51-000-001
Removal of the APU Generator
AMM 24-23-51-400-001
Installation of the APU Generator
AMM 49-00-00-710-010
Operational Test of the APU
AMM 49-11-11-000-004
Removal of the Power Plant (APU) (131-9(A))
AMM 49-11-11-400-004
Installation of the Power Plant (APU) (131-9(A))
AMM 49-16-00-100-005
Cleaning of the APU Air Intake (131-9(A))
AMM 49-16-00-200-002
Detailed Inspection of APU Air Intake, Diffuser Elbow, Seals and Felt Metal (131-9(A))
AMM 49-23-51-000-004
Removal of the Inlet Guide Vane - Actuator (131-9(A))
AMM 49-23-51-400-004
Installation of the Inlet Guide Vane - Actuator (131-9(A))
AMM 49-32-11-000-003
Removal of the Fuel Control Unit (FCU) (131-9(A))
AMM 49-32-11-400-003
Installation of the Fuel Control Unit (FCU) (131-9(A))
AMM 49-51-51-000-004
Removal of the Load Control Valve (131-9(A))
AMM 49-51-51-400-004
Installation of the Load Control Valve (131-9(A))
AMM 49-52-51-000-002
Removal of the Cooling Fan (131-9(A))
AMM 49-52-51-400-002
Installation of the Cooling Fan (131-9(A))
AMM 49-90-00-600-007
Check Oil Level and Replenish (131-9(A))
AMM 49-91-41-200-002
Remove and Discard Oil Filter Elements (131-9(A))
AMM 49-91-42-200-004
Inspection of the Metal Chip Detector (131-9(A))
AMM 49-91-42-400-003
Installation of the Drain Plug (131-9(A))
AMM 49-91-44-000-004
Removal of the Oil Cooler (131-9(A))
AMM 49-91-44-000-802
Removal of the Oil-Cooler Transfer Tubes (131-9(A))
AMM 49-91-44-400-004
Installation of the Oil Cooler (131-9(A))
AMM 49-91-44-400-802
Installation of the Oil-Cooler Transfer Tubes (131-9(A))
AMM 49-91-45-000-003
Removal of Oil Lube Module (131-9(A))
AMM 49-91-45-400-003
Installation of Oil Lube Module (131-9(A))
AMM 49-91-49-000-003
Removal of De-Oil Solenoid (131-9(A))
AMM 49-91-49-400-003
Installation of De-Oil Solenoid (131-9(A))
AMM 49-93-16-000-003
Removal of Oil Level Switch (131-9(A))
AMM 49-93-16-400-003
Installation of Oil Level Switch (131-9(A))
3. Fault Confirmation
Subtask 49-00-81-710-196-A ** ON A/C NOT FOR ALL
A. If it is necessary to confirm the fault:
NOTE: Before you do the pre-conditioning with the APU, make sure that the external area around of the APU air intake and the diverter is clean.
Make sure that no exhaust gases from main engines and/or ground support equipment go into the APU air intake during the pre-conditioning.
NOTE: If the APU did operate during fluid de-icing operations, it can be that the APU Inlet and the APU compressors are contaminated.
Then do the cleaning and testing as given in the Para. 4.C. before you do the fault confirmation.
4. Fault Isolation
Subtask 49-00-81-810-136-A ** ON A/C NOT FOR ALL
A. If you smell fumes in the cabin during the pre-conditioning with the APU and there is no oil smoke on the exhaust during the operation of the APU.
NOTE: Do the cleaning and testing as given in the Para. 4.B. after each repair step during the fault isolation.
If you fail to do this, the fault may continues.
  • examine the outer and inner surfaces and the flexible seals on the air intake diffuser and elbow and make sure that they are clean,
  • examine the surfaces of the air intake diverter and the air inlet duct and make sure that they are clean,
  • examine the surfaces and the flexible seals of the APU access doors and make sure that they are clean.
NOTE: Do the checks with a LIGHT SOURCE - ULTRA-VIOLET.
Make sure that there is no contamination of oil, fuel, grease, other unwanted material and/or remaining signs of contamination.
   (1) If there is contamination of oil, fuel or grease on the outer and/or inner surfaces of the air intake system components and/or the APU access doors:
  • identify the type of contamination and the area of the source,
  • examine the plumbing/tubing and the APU component interfaces in that area for leaks.
NOTE: If necessary, do the checks with a LIGHT SOURCE - ULTRA-VIOLET.
Do the check very carefully on the:
  • OIL COOLER ,
  • OIL PUMP ASSY ,
  • GEN-APU [8XS] ,
  • FUEL CONTROL UNIT P19 ,
  • INLET GUIDE-VANE ACTUATOR P21 .
NOTE: If you cannot identify the leak(s) when the APU does not operate:
  • start and operate the APU with no bleed air supply and no APU generator load AMM 49-00-00-710-010,
  • let the APU operate for 15 minutes for thermal stabilazation,
  • do a leak check on the APU with a black light lamp,
  • do the APU shutdown AMM 49-00-00-710-010,
  • immediately after the APU has stopped, examine the APU carefully with a black light lamp to identify the leak(s).
     (a) If there is presence of oil at the Load Compressor Cavity drain.
     (b) If there is a leak on the plumbing/tubing:
  • do the repair and replace the tubes, the connectors and the seals as necessary.
     (c) If there is oil leakage in the area of the cooling fan:
     (d) If there is oil leakage in the area of the oil cooler:
     (e) Remove the cooling-fan discharge-duct AMM 49-52-51-000-002 and examine if there is oil contamination inside the duct.
If there is oil contamination inside cooling-fan discharge duct and the inside of the APU inlet plenum is clean:
  • do a further inspection of the cooling fan.
     (f) If there is oil leakage in the area of the oil pump assy:
     (g) If there is oil leakage in the area of the APU generator:
     (h) If there is oil leakage in the area of the lupe pump filter and/or the generator scavenge filter:
     (i) If there is oil leakage at the magnetic chip detector:
     (j) If there is oil leakage at the oil-sump drain-plug housing:
     (k) If there is oil leakage at the oil level switch/gearbox interface:
     (l) If there is oil leakage at the de-oil solenoid/gearbox interface:
     (m) If there is fuel leakage in the area of the fuel control unit:
     (n) If there is fuel leakage in the area of the inlet guide-vane actuator:
   (2) If you find other unwanted material on the surfaces of the air intake system components :
  • identify the material and its source,
   (3) If there is no external contamination:
  • if the oil level in the oil reservoir is above the FULL mark on the oil sight glas , correct it with the overflow drain tool AMM 49-90-00-600-007.
NOTE: If the APU oil reservoir was filled above the FULL mark on the oil sight glass:
During APU operation the oil expands which could create an over-filled condition, resulting in leakage and possible oil smell in the cabin.
  • remove the APU Bleed-Air Duct Elbow AMM 49-11-11-000-004,
  • remove the Load Control Valve P12 AMM 49-51-51-000-004.
  • examine the removed components with a LIGHT SOURCE - ULTRA-VIOLET and make sure that you do not find signs of contamination.
     (a) If there are signs of contamination:
       1 If the fault continues:
Subtask 49-00-81-810-136-B ** ON A/C NOT FOR ALL
A. If you smell fumes in the cabin during the pre-conditioning with the APU and there is no oil smoke on the exhaust during the operation of the APU.
NOTE: Do the cleaning and testing as given in the Para. 4.B. after each repair step during the fault isolation.
If you fail to do this, the fault may continues.
  • examine the outer and inner surfaces and the flexible seals on the air intake diffuser and elbow and make sure that they are clean,
  • examine the surfaces of the air intake diverter and the air inlet duct and make sure that they are clean,
  • examine the surfaces and the flexible seals of the APU access doors and make sure that they are clean.
NOTE: Do the checks with a LIGHT SOURCE - ULTRA-VIOLET.
Make sure that there is no contamination of oil, fuel, grease, other unwanted material and/or remaining signs of contamination.
   (1) If there is contamination of oil, fuel or grease on the outer and/or inner surfaces of the air intake system components and/or the APU access doors:
  • identify the type of contamination and the area of the source,
  • examine the plumbing/tubing and the APU component interfaces in that area for leaks.
NOTE: If necessary, do the checks with a LIGHT SOURCE - ULTRA-VIOLET.
Do the check very carefully on the:
  • OIL COOLER (8079KM),
  • OIL PUMP ASSY (8080KM),
  • GEN-APU [8XS] ,
  • FUEL CONTROL UNIT (8022KM),
  • INLET GUIDE-VANE ACTUATOR (8014KM).
NOTE: If you cannot identify the leak(s) when the APU does not operate:
  • start and operate the APU with no bleed air supply and no APU generator load AMM 49-00-00-710-010,
  • let the APU operate for 15 minutes for thermal stabilazation,
  • do a leak check on the APU with a black light lamp,
  • do the APU shutdown AMM 49-00-00-710-010,
  • immediately after the APU has stopped, examine the APU carefully with a black light lamp to identify the leak(s).
     (a) If there is a presence of oil at the Load Compressor Cavity drain.
     (b) If there is a leak on the plumbing/tubing:
  • do the repair and replace the tubes, the connectors and the seals as necessary.
     (c) If there is oil leakage in the area of the cooling fan:
     (d) If there is oil leakage in the area of the oil cooler:
     (e) Remove the cooling-fan discharge-duct AMM 49-52-51-000-002 and examine if there is oil contamination inside the duct.
If there is oil contamination inside cooling-fan discharge duct and the inside of the APU inlet plenum is clean:
  • do a further inspection of the cooling fan.
     (f) If there is oil leakage in the area of the oil pump assy:
     (g) If there is oil leakage in the area of the APU generator:
     (h) If there is oil leakage in the area of the lupe pump filter and/or the generator scavenge filter:
     (i) If there is oil leakage at the magnetic chip detector:
     (j) If there is oil leakage at the oil-sump drain-plug housing:
     (k) If there is oil leakage at the oil level switch/gearbox interface:
     (l) If there is oil leakage at the de-oil solenoid/gearbox interface:
     (m) If there is fuel leakage in the area of the fuel control unit:
     (n) If there is fuel leakage in the area of the inlet guide-vane actuator:
   (2) If you find other unwanted material on the surfaces of the air intake system components :
  • identify the material and its source,
   (3) If there is no external contamination:
  • if the oil level in the oil reservoir is above the FULL mark on the oil sight glas , correct it with the overflow drain tool AMM 49-90-00-600-007.
NOTE: If the APU oil reservoir was filled above the FULL mark on the oil sight glass:
During APU operation the oil expands which could create an over-filled condition, resulting in leakage and possible oil smell in the cabin.
  • remove the APU Bleed-Air Duct Elbow AMM 49-11-11-000-004,
  • remove the Load Control Valve (8050KM) AMM 49-51-51-000-004.
  • examine the removed components with a LIGHT SOURCE - ULTRA-VIOLET and make sure that you do not find signs of contamination.
     (a) If there are signs of contamination:
       1 If the fault continues:
Subtask 49-00-81-710-197-A ** ON A/C NOT FOR ALL
B. Cleaning and Testing
   (1) If an external leak was identified on the APU:
  • do the repair,
  • clean the area,
  • start and operate the APU with no bleed air supply and no APU generator load AMM 49-00-00-710-010,
  • let the APU operate 15 minutes for thermal stabilization,
  • do a leak check on the APU with a black light lamp,
  • do the APU shutdown AMM 49-00-00-710-010,
  • immediately after the APU has stopped, examine the area carefully and make sure that there is no leak,
  • if there is a leak (the repair was not succesful), do the repair and/or replace as necessary.
  • if there is no leak (the repair was successful), continue as given subsequent.
If no external leak was identified on the APU, do the procedure as given subsequent.
   (2) If dirty, clean the APU compartment.
   (3) If dirty, clean the air intake diverter, the air inlet duct and the air intake diffuser and elbow AMM 49-16-00-100-005.
   (4) Do a check and make sure that the flexible seals on the air intake system are in correct condition AMM 49-16-00-200-002 and clean.
   (5) Clean the APU bleed air duct, the pneumatic ducts of the aircraft and the environmental control system AMM 21-00-00-615-001 or AMM 21-00-00-615-002 and AMM 21-00-00-100-001.
   (6) Do the pre-conditioning with the APU AMM 12-33-21-618-001 and make sure that you do not smell fumes in the cabin and/or there is no oil smoke at the APU exhaust.
   (7) Do a leak check and make sure that there is no fuel leak and/or no oil leak on the APU and/or the APU generator.
NOTE: Do the leak check with a LIGHT SOURCE - ULTRA-VIOLET.
[Rev.8 from Aug 2018] 2026.04.04 04:38:47 UTC
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