Removal of the Environmental Control System (ECS) Mid-Y Duct and the Intermediate Pressure Check Valve (IPCV)

TASK 36-11-41-000-802-A
Removal of the Environmental Control System (ECS) Mid-Y Duct and the Intermediate Pressure Check Valve (IPCV)

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

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.

WARNING: ALWAYS USE APPLICABLE GLOVES TO TOUCH HOT PARTS. HOT PARTS CAN CAUSE INJURY TO PERSONS.

WARNING: WEAR APPLICABLE PERSONAL PROTECTIVE EQUIPMENT (PPE) WHEN YOU DO THIS TASK. BEFORE YOU USE PPE, READ, UNDERSTAND AND OBEY ALL INSTRUCTIONS FOR ITS USE. THESE INSTRUCTIONS INCLUDE INSTRUCTIONS FROM THE MANUFACTURER, YOUR EMPLOYER AND GOVERNMENT REGULATIONS. YOU CAN GET INJURED IF YOU DO NOT USE PPE. GET INSTRUCTIONS FROM YOUR EMPLOYER ON WHICH PPE IS NECESSARY.

ZONE: 454
ZONE: 464

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)-ADJUSTABLE
No specific	AR	COVER - PROTECTION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
454	HOT SECTION
464	HOT SECTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 49-00-00-860-009-A	APU Shutdown by External Power (131-9(A))
TASK 49-00-00-860-009-A-01	APU Shutdown by Batteries (131-9(A))
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 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
ECS Mid-Y Duct and Intermediate Pressure Check Valve (IPCV)

3. Job Set-up
Subtask 36-11-41-861-057-A ** ON A/C NOT FOR ALL

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002) or (Ref. AMM TASK 24-41-00-861-002).

Subtask 36-11-41-941-056-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) On AIR COND panel 30VU:
(a) Make sure that the ENG 1(2) BLEED pushbutton switch is released (OFF legend on).
(b) Make sure that the APU BLEED pushbutton switch is released (ON legend off).
(c) Put a WARNING NOTICE(S) in position to tell persons not to operate the pneumatic system.
(2) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
(3) On the access door 191DB, on the HP ground connector:
(a) Put a WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.

Subtask 36-11-41-865-060-A ** ON A/C NOT FOR ALL

C. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22

Subtask 36-11-41-010-071-A ** ON A/C NOT FOR ALL

D. 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

Subtask 36-11-41-040-062-A ** ON A/C NOT FOR ALL

E. 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).

Subtask 36-11-41-010-072-A ** ON A/C NOT FOR ALL

F. Get Access
(1) Open the right thrust-reverser cowl-door (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
462AR
(2) Put an ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE in position below the fan cowl doors.

4. Procedure
Subtask 36-11-41-020-054-A ** ON A/C NOT FOR ALL

A. Removal of the ECS Mid-Y Duct and the IPCV
(1) If you use the APU to energize the electrical circuits, stop the APU:

For GTCP 36-300 APU (Ref. AMM D/O 49-00-00-86)
For APS 3200 (Ref. AMM D/O 49-00-00-86)
For 131-9(A) APU (Ref. AMM TASK 49-00-00-860-009).

(2) In the cockpit, on the SD bleed page:
(a) Make sure that the pressure and the temperature of the bleed-air duct system are in ambient conditions.

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

WARNING: DO NOT TOUCH THE UNIT UNTIL IT IS SUFFICIENTLY COOL TO PREVENT BURNS WHEN YOU DO THE MAINTENANCE TASK(S).

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

CAUTION: USE A SECOND WRENCH TO HOLD THE MATING PARTS WHEN YOU LOOSEN OR TIGHTEN THE TUBE OR HOSE NUTS. IF YOU DO NOT OBEY THIS INSTRUCTION, YOU CAN TWIST THE TUBES OR HOSES OR CAUSE DAMAGE TO THEM.

(3) Remove the IPCV (14) and the mid-Y duct (11) as follows:

NOTE: Two persons are necessary for this procedure.

(a) Loosen the pylon High Pressure Valve (HPV) sense-tube-nut that is attached to the mid-Y duct (11).
(b) Loosen the HPV muscle sense-tube-nut that is attached to the mid-Y duct (11).
(c) Loosen the Pressure Regulating Valve (PRV) muscle sense-tube-nut that is attached to the starter duct.
(d) Remove the bolts (5), washers (6), bushings (7) and nuts (8) that attach the link assemblies to the starter duct:
1 If necessary, adjust the link assemblies for a easier removal of the hardware as follows:

WARNING: USE GOGGLES WHEN YOU REMOVE OR INSTALL SAFETY CABLE. EACH TIME YOU CUT SAFETY CABLE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE SAFETY CABLE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

a Cut the safety cable on the applicable link assembly nut.
b Loosen the applicable link assembly nut.
c Adjust the link assembly until you can remove the hardware that attaches the link assembly to the starter duct.
(e) Examine the bolts (5), washers (6), bushings (7) and nuts (8) for damage:
1 If you find damage, discard the damaged part.
2 If there is no damage, keep the part for the installation procedure.
(f) Remove the bolts (10) and the washers (9) that attach the clamps and the ECS electrical harness to the mid-Y duct (11).
(g) Remove the V-band coupling (2) that attach the LP duct to the engine.
(h) Carefully disconnect the pylon HPV sense-tube (1) from the mid-Y duct (11). Do not damage the fittings on the pylon HPV sense-tube (1) and the mid-Y duct (11).
(i) Carefully disconnect the HPV muscle sense-tube (3) from the mid-Y duct (11). Do not damage the fittings on the HPV muscle sense-tube (3) and the mid-Y duct (11).
(j) Carefully disconnect the PRV muscle sense-tube (4) from the starter duct. Do not damage the fittings on the PRV muscle sense-tube (4) and the starter duct.
(k) Remove the V-band couplings (12) that attaches the mid-Y duct (11) to the PRV, HPV, IPCV (14) and LP duct.
(l) Move the LP duct and the starter duct a small distance to get a clearance between them.
(m) Remove the mid-Y duct (11) and the IPCV (14) from the engine.
(n) Remove and discard the seals (13).
(o) Install the COVER - PROTECTION on the PRV, HPV, LP duct, mid-Y duct (11), IPCV (14), PRV muscle sense-tube (4), HPV muscle sense-tube (3) and pylon HPV sense-tube (1).
(4) Make sure that the work area is clean and clear of tools and other items.

[Rev.10 from 2021] 2026.04.01 01:09:07 UTC