Fuel or Hydraulic or Oil Leakage Limits [CFML]

TASK 71-00-00-790-805-A
Fuel or Hydraulic or Oil Leakage Limits

ZONE: 400

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS

C. Referenced Information

REFERENCE	DESIGNATION
TASK 29-00-00-790-001-A	Check of the External Leaks of the Hydraulic Components
TASK 71-00-00-790-806-A	Drain Mast Leakage Identification Procedure
TASK 71-00-00-860-827-A	Start the Engine (Normal Automatic Start)
TASK 71-00-00-860-829-A	Engine Shutdown
TASK 72-00-00-200-818-A	Inspection/Check After the Engine has Exceeded the Operational Limits
TASK 72-00-00-200-823-A	Over Serviceable Limit Extension
TASK 72-63-43-000-801-A	Removal of the Rotating Seals of the Accessory Gearbox (AGB)
TASK 72-63-43-400-801-A	Installation of the Rotating Seals of the Accessory Gearbox (AGB)
TASK 73-11-05-000-801-A	Removal of the Main Fuel Pump
TASK 73-11-05-400-801-A	Installation of the Main Fuel Pump
TASK 75-11-05-000-801-A	Removal of the Starter Bleed/Booster Anti-Ice Valve
TASK 75-11-05-400-801-A	Installation of the Starter Bleed/Booster Anti-Ice Valve
TASK 75-21-05-000-801-A	Removal of the High Pressure Turbine (HPT) Active Clearance Control (ACC) Valve
TASK 75-21-05-400-801-A	Installation of the High Pressure Turbine (HPT) Active Clearance Control (ACC) Valve
TASK 75-22-05-000-801-A	Removal of the Low Pressure Turbine Active Clearance Control (LPT ACC) Valve
TASK 75-22-05-400-801-A	Installation of the Low Pressure Turbine Active Clearance Control (LPT ACC) Valve
TASK 75-23-05-000-801-A	Removal of the Left Modulated Turbine Cooling (MTC) Actuator
TASK 75-23-05-400-801-A	Installation of the Left Modulated Turbine Cooling (MTC) Actuator
TASK 75-31-05-000-801-A	Removal of the Left Variable Bleed Valve (VBV) Actuator
TASK 75-31-05-000-802-A	Removal of the Right Variable Bleed Valve (VBV) Actuator
TASK 75-31-05-400-801-A	Installation of the Left Variable Bleed Valve (VBV) Actuator
TASK 75-31-05-400-802-A	Installation of the Right Variable Bleed Valve (VBV) Actuator
TASK 75-32-05-000-801-A	Removal of the Right Variable Stator Vane (VSV) Actuator
TASK 75-32-05-000-802-A	Removal of the Left Variable Stator Vane (VSV) Actuator
TASK 75-32-05-400-801-A	Installation of the Right Variable Stator Vane (VSV) Actuator
TASK 75-32-05-400-802-A	Installation of the Left Variable Stator Vane (VSV) Actuator
TASK 75-33-05-000-801-A	Removal of the Transient Bleed Valve (TBV)
TASK 75-33-05-400-801-A	Installation of the Transient Bleed Valve (TBV)
TASK 79-00-00-200-806-A	Visual Inspection of the A, B and C Sumps, the Accessory Gearbox (AGB) and the Transfer Gearbox Sump Scavenge Screen Plugs for Debris
TASK 79-21-05-210-801-A	Visual Inspection of the Oil filter Cartridge
TSM 28-11-00-810-814	Fuel - Fuel Leak from Pylon Drain Ports
Check of Fuel Leak at the Aircraft Drain Mast Assembly

3. Job Set-up
Subtask 71-00-00-941-161-A

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put a WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch
The ENG/MASTER 1(2) control switch.

(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

4. Procedure
Subtask 71-00-00-790-072-A

A. Fuel or Hydraulic or Oil Leakage Limits

NOTE: Use a plastic container to collect leakage after run-up.

(1) Measure fuel leakage at the aircraft drain mast assembly:
(a) Static fuel leak check: with non-running engine (static fuel leak), do a check at the aircraft drain mast assembly:
1 If the fuel leakage rate is less than 60 drops per minute (180 ml/h or 3 cc/min), no maintenance action is necessary.

Check of Fuel Leak at the Aircraft Drain Mast Assembly

2 If the fuel leakage rate is more than 60 drops per minute (180 ml/h or 3 cc/min), do the dynamic fuel leak check.:

Check of Fuel Leak at the Aircraft Drain Mast Assembly

(b) Dynamic fuel leak check:
1 Start the Engine (Ref. AMM TASK 71-00-00-860-827).

2 Let the engine become stable at minimum idle for five minutes.
3

Check of Fuel Leak at the Aircraft Drain Mast Assembly

a If the fuel leakage rate is less than 60 drops per minute (180 ml/h or 3 c c/min), no maintenance action is necessary.
b If the fuel leakage rate is more than 60 drops per minute (180 ml/h or 3 cc/min), but less than 90 drops per minute (270 ml/h or 4.5 cc/min), do a corrective action within 25 cycles not interfering with revenue service operation.
c If the fuel leakage rate is more than 90 drops per minute (270 ml/h or 4. 5 cc/min), do a leakage test (Ref. AMM TASK 71-00-00-790-806) to identify the defective element.
4 Stop the engine (Ref. AMM TASK 71-00-00-860-829)
(2) Measure oil leakage at the drain mast assembly:
(a) If the oil leakage rate at the drain mast assembly is less than seven drops per minute (20 ml/h or 1 cc/3 min), no maintenance action is necessary.
(b) If the oil leakage rate at the drain mast assembly is more than seven drops per minute (20 ml/h or 1 cc/3 min), do the following steps:
1 Start the engines (Ref. AMM TASK 71-00-00-860-827)
2 Let the engine become stable at minimum idle for five minutes.
3 Slowly increase the power of the non-tested engine to 60 percent N1.
4 Slowly accelerate the tested engine and stabilize at 70 percent N1 for five minutes.
5 Slowly decrease the power of the two engines to minimum idle and let th em become stable for five minutes.
6 Stop the engines (Ref. AMM TASK 71-00-00-860-829)
7 Measure the individual leakage quantities collected from each plastic container.
(3) Measure hydraulic leakage at the drain mast assembly: (Ref. AMM TASK 29-00-00-790-001)
(4) Measure the individual leak quantities and look for the items that follow:

NOTE: Whenever the serviceable limits for the following are exceeded, refer to the overserviceable limit extension if necessary (Ref. AMM TASK 72-00-00-200-823).

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.The oil source
A.A-sump	60 ml/h (20 drops/min) NOTE: To confirm the oil leak rate, CFM recommends to measure the average oil leak during a five minutes ground idle.	Continued in service limit: Between 20 drops/min and 40 drops/min, the engine can continue in operation for 100 cycles, if the oil consumption and oil rate are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). For leaks greater than 60 ml/h (20 drops/min) but less than 120 ml/h (40 drops/min), perform the following maintenance inspections within 100 cycles: Scavenge screen inspection (Ref. AMM TASK 79-00-00-200-806) Oil filter inspection (Ref. AMM TASK 79-21-05-210-801) Make sure that the oil consumption rate and oil pressure are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). If the troubleshooting did not decrease the leak rate below 20 drops/min or if the leak rate is more than 40 drops/min, Contact CFM for further instruction.
B.B-sump NOTE: B-sump drain is linked to B-sump and auxiliary tubes.	60 ml/h (20 drops/min) NOTE: To confirm the oil leak rate, CFM recommends to measure the average oil leak during a five minutes ground idle.	Continued in service limit: Between 20 drops/min and 40 drops/min, the engine can continue in operation for 100 cycles, if the oil consumption and oil rate are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). For leaks greater than 60 ml/h (20 drops/min) but less than 120 ml/h (40 drops/min), perform the following maintenance inspections within 100 cycles: Scavenge screen inspection (Ref. AMM TASK 79-00-00-200-806) Oil filter inspection (Ref. AMM TASK 79-21-05-210-801): Make sure that the oil consumption rate and oil pressure are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). If the troubleshooting did not decrease the leak rate below 20 drops/min or if the leak rate is more than 40 drops/min, contact CFM for further instruction.
C.C-sump	60 ml/h (20 drops/min) NOTE: Leak rate measured after shutdown.	Continued in service limit: Between 20 drops/min and 40 drops/min the engine can continue in operation for 100 cycles, if the oil consumption and oil rate are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). For leaks greater than 60 ml/h (20 drops/min) but less than 120 ml/h (40 drops/min), perform the following maintenance inspections within 100 cycles: Scavenge screen inspection (Ref. AMM TASK 79-00-00-200-806) Oil filter inspection (Ref. AMM TASK 79-21-05-210-801) Make sure that the oil consumption rate and oil pressure are within serviceable limits (Ref. AMM TASK 72-00-00-200-818). If the troubleshooting did not decrease the leak rate below 20 drops/min or if leak rate is more than 40 drops/min, contact CFM for further instruction.
D.Accessory Gearbox (AGB) rotating seal - Fuel pump pad	20 ml/h (1 cc/3 min) (7 drops/min)	Replace the seal (Ref. AMM TASK 72-63-43-000-801) (Ref. AMM TASK 72-63-43-400-801).
E.AGB rotating seal - Hand cranking pad	20 ml/h (1 cc/3 min) (7 drops/min)	Replace the seal (Ref. AMM TASK 72-63-43-000-801) (Ref. AMM TASK 72-63-43-400-801).
F.AGB rotating seal - Integrated Drive Generator (IDG) pad	20 ml/h (1 cc/3 min) (7 drops/min)	Replace the seal (Ref. AMM TASK 72-63-43-000-801) (Ref. AMM TASK 72-63-43-400-801).
G.AGB rotating seal - Engine Driven Pump (EDP) pad	20 ml/h (1 cc/3 min) (7 drops/min)	Replace the seal (Ref. AMM TASK 72-63-43-000-801) (Ref. AMM TASK 72-63-43-400-801).
2.The fuel source
A.main fuel pump	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the main fuel pump (Ref. AMM TASK 73-11-05-000-801) (Ref. AMM TASK 73-11-05-400-801).
B.Start bleed/booster anti-ice valve	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the start bleed/booster anti-ice valve (Ref. AMM TASK 75-11-05-000-801) (Ref. AMM TASK 75-11-05-400-801). NOTE: The start bleed/booster anti-ice valve, right modulated turbine cooling actuator, Transient Bleed Valve (TBV), right variable bleed vane actuator, and right variable stator vane actuator share the same fuel drain line at the drain mast manifold. To isolate the leaking unit, disconnect the drain tubes at each component.
C.Modulated turbine cooling actuators	270 ml/h/actuator (4.5 cc/min/actuator) (90 drops/min/actuator)	Replace the modulated turbine cooling actuator (Ref. AMM TASK 75-23-05-000-802) (Ref. AMM TASK 75-23-05-000-801) (Ref. AMM TASK 75-23-05-400-801).
D.High Pressure Turbine Active Clearance Control (HPTACC) valve	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the HPTACC valve (Ref. AMM TASK 75-21-05-000-801) (Ref. AMM TASK 75-21-05-400-801). NOTE: The HPTACC valve, Low Pressure Turbine Active Clearance Control (LPTACC) valve, left modulated turbine cooling actuator, left variable stator vane actuator, and left VSV actuator share the same fuel drain line at the drain mast manifold. To isolate the leaking unit, disconnect the drain tubes at each component.
E.LPTACC	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the LPTACC Valve (Ref. AMM TASK 75-22-05-000-801) (Ref. AMM TASK 75-22-05-400-801).
F.TBV	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the TBV (Ref. AMM TASK 75-33-05-000-801) (Ref. AMM TASK 75-33-05-400-801).
G.variable bleed valve actuator	270 ml/h/actuator (4.5 cc/min/actuator) (90 drops/min/actuator)	Replace the variable bleed valve actuator (Ref. AMM TASK 75-31-05-000-801) (Ref. AMM TASK 75-31-05-400-801) (Ref. AMM TASK 75-31-05-000-802) (Ref. AMM TASK 75-31-05-400-802).
H.VSV	270 ml/h (4.5 cc/min) (90 drops/min)	Replace the VSV (Ref. AMM TASK 75-32-05-000-801) (Ref. AMM TASK 75-32-05-400-801) (Ref. AMM TASK 75-32-05-000-802) (Ref. AMM TASK 75-32-05-400-802).
J.Pylon core drain mast	None	Do the troubleshooting procedure TSM 28-11-00-810-814.
K.Aft pylon drain mast	None	Do the troubleshooting procedure TSM 28-11-00-810-814.

[Rev.10 from 2021] 2026.04.01 04:43:02 UTC