Fuel/Oil Leaks from the Overboard Drains on Engine 1

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1. Possible Causes
· FMU ( 4000KC )
· PUMPS-LP/HP FUEL (2001EM1)
· ACTUATOR-MASTER, LPC BLEED ( 4021KS )
· LPC bleed-slave actuator
· ACTUATOR-VSV ( 4022KS )
· VALVE-FUEL DIVERTER AND RETURN ( 4018KS )
· ACTUATOR-ACC ( 4027KS )
· IDG ( 4000XU )
· ACOC ( 6002EM )
· STARTER ( 100KM )
· PUMP VARIABLE DTS ( 1030GK )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 24-21-51-000-040 Removal of the Integrated Drive Generator - IDG 1(2)
Ref. AMM 24-21-51-400-040 Installation of the Integrated Drive Generator - IDG 1(2)
Ref. AMM 29-11-51-000-040 Removal of the Green Engine Pump
Ref. AMM 29-11-51-400-040 Installation of the Green Engine Pump
Ref. AMM 71-00-00-710-046 Test No.2 : Wet Motor Leak Check
Ref. AMM 73-12-41-000-010 Removal of the Low Pressure (LP)/High Pressure (HP) Fuel Pump
Ref. AMM 73-12-41-400-010 Installation of the Low Pressure (LP)/High Pressure (HP) Fuel Pump
Ref. AMM 73-13-42-000-010 Removal of the Fuel Diverter and Return Valve
Ref. AMM 73-13-42-400-010 Installation of the Fuel Diverter and Return Valve
Ref. AMM 73-22-52-000-010 Removal of the Fuel Metering Unit (FMU)
Ref. AMM 73-22-52-400-010 Installation of the Fuel Metering Unit (FMU)
Ref. AMM 75-24-52-000-010 Removal of the High Pressure Turbine/Low Pressure Turbine (HPT/
LPT) Valve Actuator
Ref. AMM 75-24-52-400-010 Installation of the High Pressure Turbine/Low Pressure Turbine (HPT/
LPT) Valve Actuator
REFERENCE DESIGNATION
Ref. AMM 75-31-42-000-010 Removal of the Low Pressure Compressor (LPC) Bleed-Master Actuator
Ref. AMM 75-31-42-400-010 Installation of the Low Pressure Compressor (LPC) Bleed-Master Actuator
Ref. AMM 75-31-43-000-010 Removal of the Low Pressure Compressor (LPC) Bleed-Slave Actuator
Ref. AMM 75-31-43-400-010 Installation of the Low Pressure Compressor (LPC) Bleed-Slave Actuator
Ref. AMM 75-32-41-000-010 Removal of the Variable Stator Vane (VSV) Actuator
Ref. AMM 75-32-41-400-010 Installation of the Variable Stator Vane (VSV) Actuator
Ref. AMM 79-21-42-000-010 Removal of the Air Cooled Oil Cooler
Ref. AMM 79-21-42-400-010 Installation of the Air Cooled Oil Cooler
Ref. AMM 80-13-41-000-010 Removal of the Starter
Ref. AMM 80-13-41-400-010 Installation of the Starter
3. Fault Confirmation
Subtask 71-70-00-710-050-A
A. Test
Not applicable, the fault is evident.
4. Fault Isolation
Subtask 71-70-00-810-050-A
A. Do the leak check, test No. 2 Ref. AMM 71-00-00-710-046 .
(1) Make an inspection of the fuel and lubrication system lines, fittings and accessories for external leaks.
(a) If there is external leak, repair the defective items.
(2) If the leak check always shows fuel/oil leaks from the overboard drain
NOTE: If you can identify the leak source and you are sure it is:
- fuel: only the steps 4.A.(2)(a) through 4.A.(2)(g) are applicable
- oil: only the steps 4.A.(2)(h) through 4.A.(2)(k) are applicable.
(a) Replace the FMU ( 4000KC ) , Ref. AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(b) If the fault continues:
· replace the PUMPS-LP/HP FUEL (2001EM1) , Ref. AMM 73-12-41-000-010 and Ref.
AMM 73-12-41-400-010 .
(c) If the fault continues:
· replace the ACTUATOR-MASTER, LPC BLEED ( 4021KS ) , Ref. AMM 75-31-42-000-010
and Ref. AMM 75-31-42-400-010 .
(d) If the fault continues:
· replace the LPC bleed-slave actuator , Ref. AMM 75-31-43-000-010 and Ref.
AMM 75-31-43-400-010 .
(e) If the fault continues:
· replace the ACTUATOR-VSV ( 4022KS ) , Ref. AMM 75-32-41-000-010 and Ref.
AMM 75-32-41-400-010 .
(f) If the fault continues:
· replace the VALVE-FUEL DIVERTER AND RETURN ( 4018KS ) , Ref.
AMM 73-13-42-000-010 and Ref. AMM 73-13-42-400-010 .
(g) If the fault continues:
· replace the ACTUATOR-ACC ( 4027KS ) , Ref. AMM 75-24-52-000-010 and Ref.
AMM 75-24-52-400-010 .
(h) If the fault continues:
· replace the IDG ( 4000XU ) , Ref. AMM 24-21-51-000-040 and Ref. AMM 24-21-51-400-040 .
(i) If the fault continues:
· replace the ACOC ( 6002EM ) , Ref. AMM 79-21-42-000-010 and Ref.
AMM 79-21-42-400-010 .
(j) If the fault continues:
· replace the STARTER ( 100KM ) , Ref. AMM 80-13-41-000-010 and Ref.
AMM 80-13-41-400-010 .
(k) If the fault continues:
· replace the PUMP VARIABLE DTS ( 1030GK ) , Ref. AMM 29-11-51-000-040 and Ref.
AMM 29-11-51-400-040 .
Subtask 71-70-00-710-051-A
B. Do the leak check, test No. 2 Ref. AMM 71-00-00-710-046 . [Rev.6 from Feb 2017] 2026.04.04 04:35:08 UTC