Deactivation of the Left Modulated Turbine Cooling (MTC) Valve [CFML]

TASK 75-23-00-040-801-A
Deactivation of the Left Modulated Turbine Cooling (MTC) Valve

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.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

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)
No specific	Torque wrench: range to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2619)	Never Seez-Pure Nickel, Special
(Material No.CP8005)	lockwire 0.6 mm (0.0236 in.) dia
(Material No.CP8006)	safety cable 0.032 in. (0.8 mm) dia.

C. Work Zones and Access Panels

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

D. 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 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
Left Modulated Turbine Cooling (MTC) Valve

3. Job Set-up
Subtask 75-23-00-941-052-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 75-23-00-010-054-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 75-23-00-040-052-A

C. Deactivation of the Thrust Reverser 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 thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 75-23-00-010-055-A

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

4. Procedure
Subtask 75-23-00-020-050-A

A. Deactivation of the Left Modulated Turbine Cooling (MTC) Valve

Left Modulated Turbine Cooling (MTC) Valve

(1) Put the left MTC valve (67) in the open position with the bolt (68) installed in the normal position, see the view D of the figure.
(2) Deactivate the left MTC valve (67) as follows:

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(a) Cut the safety cable and remove the bolt (68) from the normal position, see the view E of the figure.
(b) Lubricate the bolt (68) threads and the lock-out-position threaded insert on the left MTC valve using CP2619Never Seez-Pure Nickel, Special.
(c) Align the hole in the control arm with the lock-out-position threaded insert on the MTC valve body, see the view F of the figure.
(d) Swing the MTC valve link to align the link bolt hole with the holes of the control arm and the lock-out-position threaded insert on the MTC valve body. See the view F of the figure.

NOTE: Three holes must be aligned: the control arm, the link and the lock-out-position threaded insert on the MTC valve body. Failure to secure the link may result in contact and damage between the pushrod and the link when the engine is operated.

(e) Install the bolt (68) in the lockout position, see the view G of the figure.
(f) TORQUE the bolt (68) to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

, see the view G of the figure.
(g) Install the CP8005lockwire 0.6 mm (0.0236 in.) dia or CP8006safety cable 0.032 in. (0.8 mm) dia. between the bolt (68) and the safety cable hole located on the main valve body (67).

5. Close-up
Subtask 75-23-00-410-054-A

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

Subtask 75-23-00-440-052-A

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

Subtask 75-23-00-410-055-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 13:09:11 UTC