Removal of the Pylon TRAS Tee-Piece [PW11]

TASK 78-31-49-000-813-A
Removal of the Pylon TRAS Tee-Piece

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

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 2M (6 FT) - ADJUSTABLE
No specific	AR	CAP - BLANKING
No specific	AR	CONTAINER - HYDRAULIC FLUID RESISTANT

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-31-50-000-801-A	Removal of the TRAS Hydraulic Tubes and Hoses
TASK 78-31-51-000-803-A	Removal of the Pylon Hydraulic Tubes and Hoses
Pylon TRAS Tee-Piece

3. Job Set-up
Subtask 78-31-49-941-128-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833)

Subtask 78-31-49-864-053-A ** ON A/C NOT FOR ALL

B. Depressurization of the Hydraulic Reservoirs
(1) For engine 1, depressurize the green hydraulic reservoir (Ref. AMM TASK 29-14-00-614-001).
(2) For engine 2, depressurize the yellow hydraulic reservoir (Ref. AMM TASK 29-14-00-614-001).

Subtask 78-31-49-010-227-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.

Subtask 78-31-49-040-175-A ** ON A/C NOT FOR ALL

D. Deactivation of the Thrust Reverser 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 maintenance (Ref. AMM TASK 78-30-00-040-805).

4. Procedure

CAUTION: HYDRAULIC FLUID CAN CAUSE DAMAGE TO EQUIPMENT. IF HYDRAULIC FLUID FALLS ON A SURFACE, IMMEDIATELY CLEAN THE SURFACE WITH A CLEAN CLOTH.

Subtask 78-31-49-020-191-A ** ON A/C NOT FOR ALL

A. Removal of the TRAS Tee-Piece
(1) Remove the TRAS Tee-Piece (1) from the pylon floor.
(a) Disconnect the pylon hydraulic lines from the tee-piece (1) (Ref. AMM TASK 78-31-51-000-803).
1 Disconnect the hydraulic stow tube from the tee-piece (1). Drain the hydraulic fluid from the tube into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put a CAP - BLANKING on the end of the tube.
2 Disconnect the hydraulic deploy tube from the tee-piece (1). Drain the hydraulic fluid from the tube into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put a CAP - BLANKING on the end of the tube.
3 Disconnect the hydraulic return tube from the tee-piece (1). Drain the hydraulic fluid from the tube into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put a CAP - BLANKING on the end of the tube.
(b) Disconnect the TRAS hydraulic lines from the tee-piece (1) (Ref. AMM TASK 78-31-50-000-801).
1 Disconnect the two hydraulic stow hoses from the tee-piece (1). Drain the hydraulic fluid from the hoses into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put CAP - BLANKING on the ends of the hoses.
2 Disconnect the two hydraulic deploy hoses from the tee-piece (1). Drain the hydraulic fluid from the hoses into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put CAP - BLANKING on the ends of the hoses.
3 Disconnect the two hydraulic return hoses from the tee-piece (1). Drain the hydraulic fluid from the hoses into the CONTAINER - HYDRAULIC FLUID RESISTANT. Put CAP - BLANKING on the ends of the hoses.
(c) Remove the four bolts (2) and (4) and the four washers (3) and (5) that attach the tee-piece (1) to the brackets on the pylon floor.

[Rev.10 from 2021] 2026.04.01 03:31:29 UTC