Borescope Inspection of the Oil System [CFML]

TASK 79-00-00-290-801-A
Borescope Inspection of the Oil System

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

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	1	ACCESS PLATFORM 1M(3 FT)
No specific	1	BORESCOPE SET
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-51-000-803-A	Removal of the Power Plant with 2D Bootstrap
TASK 71-00-51-400-803-A	Installation of the Power Plant with 2D Bootstrap
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
TASK 72-00-00-290-822-A	Borescope Inspection of the Low Pressure Turbine (LPT) Blades
TASK 72-30-00-290-801-A	Borescope Inspection of the High Pressure Compressor Section
TASK 78-30-00-040-809-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-809-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-806-A	Opening of the Thrust Reverser Cowl Doors
TASK 78-36-00-410-806-A	Closing of the Thrust Reverser Cowl Doors
Borescope Inspection of the Oil System
Borescope Inspection of the Oil System

3. Job Set-up
Subtask 79-00-00-941-094-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 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).

Subtask 79-00-00-010-103-A

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 79-00-00-040-065-A

C. Deactivation of the Thrust Reverser System for Ground Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 79-00-00-010-104-A

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

4. Procedure
Subtask 79-00-00-290-050-A

A. Borescope Inspection of the Oil System

NOTE: This task gives the procedure for the borescope inspection of areas of the internal engine where oil leakage could occur.

NOTE: When you do the fault isolation for an oil consumption problem, an inspection for an internal oil leak is necessary.

(1) Do the borescope inspection of High Pressure Compressor (HPC) stages 1 and 2 between the stage 1 vane and stage 1 blade using the BORESCOPE SET at the location (1) and the location (2) (Ref. AMM TASK 72-30-00-290-801) for:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Oil leakage	Not serviceable, if wet with oil and if the oil consumption is more than the specified serviceable limits.	Replace the engine (Ref. AMM TASK 71-00-51-000-803) and (Ref. AMM TASK 71-00-51-400-803).

(2) Do the borescope inspection of HPC stage 1 and 2 blades using the BORESCOPE SET at the location (1), location (2) and the location (3) (Ref. AMM TASK 72-30-00-290-801) for:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Oil leakage	Not serviceable, if wet with oil and if the oil consumption is more than the specified serviceable limits.	Replace the engine (Ref. AMM TASK 71-00-51-000-803) and (Ref. AMM TASK 71-00-51-400-803).

(3) Do the borescope inspection of three pressurization tubes through the borescope plug (4) and the borescope plug (5) for:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Oil leakage	Not serviceable, if wet with oil and if the oil consumption is more than the specified serviceable limits.	Replace the engine (Ref. AMM TASK 71-00-51-000-803) and (Ref. AMM TASK 71-00-51-400-803).

(4) If there are oil traces on the blades in the flowpath, do the borescope inspection of LP turbine using the BORESCOPE SET at the location (10) for stage 5 (Ref. AMM TASK 72-00-00-290-822).

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Oil leakage	Not serviceable, if wet with oil and if the oil consumption is more than the specified serviceable limits.	Replace the engine (Ref. AMM TASK 71-00-51-000-803) and (Ref. AMM TASK 71-00-51-400-803).

(5)

Borescope Inspection of the Oil System

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Oil leakage	Not serviceable, if wet with oil and if the oil consumption is more than the specified serviceable limits.	Replace the engine (Ref. AMM TASK 71-00-51-000-803) and (Ref. AMM TASK 71-00-51-400-803).

5. Close-up
Subtask 79-00-00-410-089-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

Subtask 79-00-00-440-065-A

B. Do the reactivation of the thrust reverser system after ground maintenance (Ref. AMM TASK 78-30-00-440-809).

Subtask 79-00-00-410-090-A

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:42:43 UTC