Inspection of the Stage 1-4 Stationary Air Seals [CFMB]

TASK 72-54-00-290-008-A
Inspection of the Stage 1-4 Stationary Air Seals

FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

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)
No specific	Torque wrench: range to between 60 and 55 lbf.in (0.68 and 0.62 m.daN )
No specific	Torque wrench: range to between 65 and 59 lbf.in (0.73 and 0.67 m.daN )
856A1320	1	BORESCOPE-KIT
856A1322	1	BORESCOPE-LIGHT SOURCE SET

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2101)	graphite grease
(Material No.CP8001)	lockwire 0.032 in. (0.8 mm) dia.
(Material No.CP8002)	lockwire 0.032 in. (0.8 mm) dia

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-B	Closing of the Fan Cowl Doors
TASK 72-00-00-200-025-A	Over-Serviceable-Limit Extensions
TASK 72-00-00-200-025-A-01	Over-Serviceable-Limit Extensions
TASK 78-30-00-081-041-B	Make the Thrust Reverser Serviceable after Maintenance
TASK 78-30-00-481-041-B	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-36-00-010-040-B	Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-B	Closing of the Thrust Reverser Doors
Location of the Borescope Ports and Possible Borescope Access Via One Instrumentation Boss
Low-Pressure Turbine Borescope Inspection
Low-Pressure Turbine Blades and Nozzle Indications Description

3. Job Set-up
Subtask 72-54-00-941-059-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 72-54-00-010-072-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Allow parts to return to ambient temperature.

Subtask 72-54-00-040-059-A ** ON A/C NOT FOR ALL

C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).

Subtask 72-54-00-010-078-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser doors (Ref. AMM TASK 78-36-00-010-040):
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR

4. Procedure
Subtask 72-54-00-010-084-A ** ON A/C NOT FOR ALL

A. Removal of the Borescope Plugs

CAUTION: DO NOT REMOVE THE NUTS WHICH HOLD THE LPT BORESCOPE PLUG BOSS. TACK WELDS HOLD THE NUTS IN THEIR POSITIONS. THE REMOVAL OF THE NUTS CAN CAUSE DAMAGE TO THE STUDS.

(1) Let the temperature of parts decrease to ambient temperature.

PRE SB CFMI 72-0376

(2) Cut and remove the lockwires. Then, remove the borescope plugs S16, S17, S18, S19 and S20.

NOTE: The borescope plugs S16 and S17 are in the same plane and located respectively, at 5:30 and 8:30 o'clock (ALF) immediately in front of combustion case aft flange. The borescope plugs S18, S19 and S20 are located at 5:00 o'clock (ALF) on the Low Pressure Turbine (LPT) case. From front to rear, they relate respectively to the 2nd, 3rd and 4th LPT stages.

END OF PRE SB CFMI 72-0376

POST SB CFMI 72-0376

(3) Cut and remove the lockwires. Then, remove the borescope plugs S16, S17.

NOTE: The borescope plugs S16 and S17 are in the same plane and located respectively, at 5:30 and 8:30 o'clock (ALF) immediately in front of the combustion case aft flange.

(4) Remove the self-locking borescope cap assemblies S18, S19 and S20.

NOTE: The borescope cap assemblies S18, S19 and S20 are located at 5:00 o'clock (ALF) on the LPT case. From front to rear, they relate respectively to the 2nd, 3rd and 4th LPT stages.

END OF SB CFMI 72-0376

Subtask 72-54-00-480-057-A ** ON A/C NOT FOR ALL

B. Install the 856A1320 BORESCOPE-KIT (856A1320P04/P05) as follows:
(1) Connect the power supply.

CAUTION: BEFORE YOU CONNECT THE POWER SUPPLY TO THE POWER SOURCE BE SURE THE ON-OFF SWITCH IS IN THE OFF POSITION AND LIGHT INTENSITY CONTROL IS SET TO MINIMUM. MAKE SURE THAT PROJECTOR AND POWER SUPPLY ARE CORRECTLY GROUNDED.

(a) Connect power supply to a grounded 110 VAC 60 Hz power source.
(2) Connect light source cable to rigid borescope and to port on 856A1322 BORESCOPE-LIGHT SOURCE SET (856A1322P02/P03/P04/P07/P08).
(3) Turn light source on; insert borescope and position it as desired for inspection.

Subtask 72-54-00-290-057-A ** ON A/C NOT FOR ALL

C. Inspect the Stage 1-4 Outer Stationary Air Seals for the Following

NOTE: The limits given below are for the stationary air seal areas you can see near the borescope holes.

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Stage 1-3 stationary air seals.
A.Rub marks or chicken marks from seal teeth.	Not deeper than 0.08 in. (2.03 mm).
2.Stage 4 stationary air seals. NOTE: This inspection is only to be done when stage 4 blades are shingled or unlatched.
A.Worn, jagged or crushed honeycomb material.	Not more than 0.08 in. (2.03 mm).	See limit extensions. (Ref. AMM TASK 72-00-00-200-025).
3.Stage 1/4 stationary air seals.
A.Distortion.	Any quantity if shroud does not come out.

Subtask 72-54-00-080-057-A ** ON A/C NOT FOR ALL

D. Removal of Borescope
(1) When inspection is complete, turn lamp switch off, leave main light source blower on for a while to cool lamp and housing.
(2) Remove the borescope.

Subtask 72-54-00-410-072-A ** ON A/C NOT FOR ALL

E. Install the Borescope Plugs

PRE SB CFMI 72-0376

(1) Apply graphite grease (Material No.CP2101) to the threads of the borescope plugs S16, S17 and install on the combustion case (S16, S17).
(2) Apply graphite grease (Material No.CP2101) to the threads of the borescope plugs S18, S19, S20 and install on the LPT case (S18, S19, S20).

END OF PRE SB CFMI 72-0376

POST SB CFMI 72-0376

(3) Apply graphite grease (Material No.CP2101) to the threads of the self-locking borescope cap assemblies S18, S19, S20 and install on the LPT case (S18, S19, S20).

END OF SB CFMI 72-0376

PRE SB CFMI 72-0376

(4) TORQUE plugs (S16, S17) to between 65 and 59 lbf.in (0.73 and 0.67 m.daN )

and safety with CP8001lockwire 0.032 in. (0.8 mm) dia. or CP8002lockwire 0.032 in. (0.8 mm) dia.
(5) TORQUE plugs (S18, S19 and S20) to between 60 and 55 lbf.in (0.68 and 0.62 m.daN )

and safety with CP8001lockwire 0.032 in. (0.8 mm) dia. or CP8002lockwire 0.032 in. (0.8 mm) dia.

END OF PRE SB CFMI 72-0376

POST SB CFMI 72-0376

(6) TORQUE the self-locking borescope cap assemblies (S18, S19 and S20) to between 60 and 55 lbf.in (0.68 and 0.62 m.daN )

NOTE: To achieve the correct installation of the self-locking borescope cap assembly, the slot of its ring must be positioned on the borescope boss lug at the final tightening.

END OF SB CFMI 72-0376

5. Close-up
Subtask 72-54-00-410-073-A ** ON A/C NOT FOR ALL

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 78-36-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 72-54-00-440-059-A ** ON A/C NOT FOR ALL

B. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041).

Subtask 72-54-00-410-079-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the WARNING NOTICE(S).

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