Removal of the Diffuser

TASK 36-11-49-000-838-A
Removal of the Diffuser

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 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: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

ZONE: 410
ZONE: 420

1. Reason for the Job

NOTE: Two persons are necessary to do this task. One person to hold the diffuser and one person to attach the bolts and washers below the pylon.

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	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
98L12003001000	1	HARNESS,SAFETY

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
410	ENG 1 PYLON BOX AND FORWARD FAIRING
420	ENG 2 PYLON BOX AND FORWARD FAIRING
191DB, 413BL, 413BR, 423BL, 423BR
FOR [1000EM1] (ENGINE-1)
437AL, 438AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR

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 27-00-00-480-002-A	Installation of the Flap/Slat Control-Lever Locking Tool (98D27803000000)
TASK 27-50-00-866-009-A-01	Retraction of the Flaps/Slats on the Ground
TASK 36-11-49-000-015-A	Removal of the Starter Valve Elbow-Duct and the Precooler Exchanger Tee-Duct in the Pylon
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 52-42-16-000-001-A	Removal of the HP Air-Ground Connector Door
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-32-00-010-010-A	Opening of the Thrust Reverser Halves
TASK 78-32-00-010-802-A	Opening of the Thrust Reverser Halves (Alternate Procedure)
Diffuser

3. Job Set-up
Subtask 36-11-49-861-135-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 36-11-49-941-154-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) Make sure that engine 1 (2) shutdown occurred not less than 5 minutes before you do this procedure.
(2) On the AIR COND section of control panel 30VU:

Make sure that the ENG 1(2) BLEED pushbutton switch is released (the OFF legend is on).
Make sure that the APU BLEED pushbutton switch is released (the ON legend is off).
Put a WARNING NOTICE(S) in position to tell persons not to operate the pneumatic system.

(3) On the ENG section of control panel 115VU:

Put a WARNING NOTICE(S) in position to tell persons not to start engine 1(2).

(4) Open access door 191DB to get access to the HP air-ground connector (Ref. AMM TASK 52-42-16-000-001).
(5) On the HP ground connector:

Put a WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.

(6) Make sure that the slats/flaps are fully retracted (Ref. AMM TASK 27-50-00-866-009).
(7) Install the slat/flap control-lever locking tool (Ref. AMM TASK 27-00-00-480-002).
(8) On the ENG section of maintenance panel 50VU:

Make sure that the ON legend of the ENG/FADEC GND PWR 1(2) pushbutton switch is off.
Put a WARNING NOTICE(S) in position to tell persons not to energize the FADEC 1(2).

Subtask 36-11-49-865-241-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 1/CTL	3HA1	D12
49VU	AIR BLEED/ENG 1/MONG	2HA1	D11
122VU	AIR BLEED/ENG 2/CTL	3HA2	Z23
122VU	AIR BLEED/ENG 2/MONG	2HA2	Z22

Subtask 36-11-49-010-300-A ** ON A/C NOT FOR ALL

D. Get Access

WARNING: BEFORE YOU START WORK, YOU MUST PUT ON A SAFETY HARNESS AND ATTACH IT TO THE ACCESS PLATFORM. WITHOUT A SAFETY HARNESS, YOU CAN FALL. THIS CAN KILL YOU OR CAUSE YOU INJURY.

(1) Put on and attach a 98L12003001000 HARNESS,SAFETY before you start work in the work area.
(2) Put an ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position above the pylon.
(3) Remove the access panels:

For the left pylon: 413BL and 413BR.
For the right pylon: 423BL and 423BR.

(4) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL and 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL and 448AR.

Subtask 36-11-49-040-183-A ** ON A/C NOT FOR ALL

E. Deactivation of the Thrust Reverser

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) Make the thrust reverser unserviceable for maintenance (Ref. AMM TASK 78-30-00-040-012).
(2) To get access to the bolts (2) and the washers (1):

Diffuser ** ON A/C NOT FOR ALL

(a) Open the thrust reverser cowl-door (Ref. AMM TASK 78-32-00-010-010) (Ref. AMM TASK 78-32-00-010-802).
(b) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below engine 1(2).

4. Procedure
Subtask 36-11-49-020-171-A ** ON A/C NOT FOR ALL

A. Removal of the Diffuser
(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 APU (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).

(3) Remove the precooler exchanger tee-duct from the pylon (Ref. AMM TASK 36-11-49-000-015).
(4) Remove the bolts (2) and the washers (1).
(5) Remove the diffuser (3).

[Rev.10 from 2021] 2026.04.01 01:11:18 UTC