Removal of the Hot Nozzle and the Bellows (131-9(A))

TASK 49-81-42-000-003-A
Removal of the Hot Nozzle and the Bellows (131-9(A))

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

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.

ZONE: 315
ZONE: 316

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 4M (13 FT)-ADJUSTABLE
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315	TAIL CONE APU AND ACCESSORY COMPARTMENT
316	TAIL CONE APU AND ACCESSORY COMPARTMENT
315AL, 316AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-81-41-000-003-A	Removal of the Exhaust Muffler (131-9(A))
TASK 49-81-41-400-003-A	Installation of the Exhaust Muffler (131-9(A))
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-18-000-001-A	Removal of the APU Exhaust Access-Fairing
Hot Nozzle and Bellows

3. Job Set-up
Subtask 49-81-42-860-055-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(2) On the panel 25VU, make sure that the APU MASTER SW p/bsw is OFF.
(3) Put a WARNING NOTICE(S) in the cockpit to tell persons not to start the APU.
(4) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).

Subtask 49-81-42-865-056-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-81-42-010-052-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE below the APU access doors 315AL and 316AR.
(2) Open the APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-010-001).
(3) Set the LIGHT SW 11LJ to the ON position.
(4) Remove the APU exhaust access-fairing 317AL (Ref. AMM TASK 52-41-18-000-001).
(5) Remove the exhaust muffler (Ref. AMM TASK 49-81-41-000-003).

4. Procedure
Subtask 49-81-42-020-052-A ** ON A/C NOT FOR ALL

A. Removal of the Hot Nozzle and the Bellows

Hot Nozzle and Bellows ** ON A/C NOT FOR ALL

(1) Remove the clamp (2).
(2) Remove the clamp (9) that attaches the drain line (10) to the drain line (8).
(3) Remove the drain line (10).
(4) Remove the clamp (7) that attaches the drain line (8) to the hot nozzle (1).
(5) Remove the drain line (8).
(6) Remove the hot nozzle (1) from the exhaust muffler (5).
(7) Remove the clamp (4) and the bellows (3).
(8) Examine the piston ring (6) for damage or wear. If the piston ring is defective, replace the exhaust muffler (5) (Ref. AMM TASK 49-81-41-000-003) and (Ref. AMM TASK 49-81-41-400-003).
(9) Examine the hot nozzle (1) and the bellows (3) for damage, chafing marks or cracks. Replace them if they are defective.

[Rev.10 from 2021] 2026.04.01 12:43:23 UTC