Visual Inspection of the Modulated Turbine Cooling Valve (PRE and POST SB LEAP 72-00-0112) [CFML]

TASK 75-23-10-210-801-A
Visual Inspection of the Modulated Turbine Cooling Valve (PRE and POST SB LEAP 72-00-0112)

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.

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	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
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 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
TASK 75-23-10-000-802-A	Removal of the Left Modulated Turbine Cooling Valve
TASK 75-23-10-400-802-A	Installation of the Left Modulated Turbine Cooling Valve
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

3. Job Set-up
Subtask 75-23-10-941-059-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 the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 75-23-10-010-071-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 75-23-10-040-062-A

C. Deactivation of the Thrust Reverser (T/R) System for 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 T/R system for maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 75-23-10-010-072-A

D. Get Access
(1) Open the T/R 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 75-23-10-210-053-A

A. Visual Inspection of the Modulated Turbine Cooling Valve

NOTE: For POST LEAP-1A Service Bulletin 72-00-0112 "Elimination of the Right Side Modulated Turbine Cooling Valve" engines, the right side modulated turbine cooling valve and actuator (aft looking forward) are removed.

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.Modulated turbine cooling valve for looseness	Not serviceable.	Tighten the installation bolts (Ref. AMM TASK 75-23-10-400-802) or for PRE SB LEAP 72-00-0112 only (Ref. AMM D/O 75-23-10-40).
2.Signs of air leaks at the connections	No leaks permitted.	If you see signs of an air leak, do this step: Disconnect the modulated turbine cooling duct from the modulated turbine cooling valve joint. Do an inspection of the seal for damage. (a) If the seal is damaged, replace the seal. NOTE: If the seal is not damaged, keep it for the installation.
3.Look for cracks and dents in the modulated turbine cooling valve	Not serviceable.	If you see a crack or dent, replace the modulated turbine cooling valve (Ref. AMM TASK 75-23-10-000-802) and (Ref. AMM TASK 75-23-10-400-802) or for PRE SB LEAP 72-00-0112 only (Ref. AMM TASK 75-23-10-000-803).

5. Close-up
Subtask 75-23-10-410-064-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the T/R 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 75-23-10-440-057-A

B. Do the reactivation of the T/R system after maintenance (Ref. AMM TASK 78-30-00-440-809).

Subtask 75-23-10-410-065-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 03:14:36 UTC