Installation of the Transducer - Differential Pressure (131-9(A))

TASK 49-51-16-400-002-A
Installation of the Transducer - Differential Pressure (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: 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	Torque wrench: range to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.03ABA1)	Synthetic base Lubricating Oil-Turbine Engine - -
(Material No.03ABB1)	Synthetic base Lubricating Oil-Turbine Engine Low Temp. -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
3	PACKING	AIPC 49-51-09-01-140
2	PACKING	AIPC 49-51-09-01-200
3	PACKING	AIPC 49-51-84-30-140
2	PACKING	AIPC 49-51-84-30-190

E. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-00-00-710-009-A	Self-Test of the ECB
TASK 49-00-00-790-006-A	Air Leak Test with closed APU Doors
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access
Differential Pressure Sensor

3. Job Set-up
Subtask 49-51-16-860-054-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) Make sure that there is a warning notice 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).
(5) Make sure that the access platform is in position below the APU compartment.
(6) Make sure that the APU access doors are open (Ref. AMM TASK 52-41-00-010-001).
(7) Make sure that the LIGHT control SW 11LJ is set to the ON position.

Subtask 49-51-16-865-054-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

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

4. Procedure
Subtask 49-51-16-420-052-A ** ON A/C NOT FOR ALL

A. Installation of the Differential Pressure Transducer
(1) Remove the blanking plug from the APU port.
(2) Lubricate the packings (2) and (3):

CAUTION: DO NOT APPLY TOO MUCH LUBRICANT ON THE PACKINGS. IF YOU DO, THE LUBRICANT CAN GO INTO THE TRANSDUCER PORT AND CAUSE A FAILURE OF THE SYSTEM.

(a) Lubricate a new AIPC 49-51-09-01-200 PACKING (2) or AIPC 49-51-84-30-190 PACKING (2) and a new AIPC 49-51-09-01-140 PACKING (3) or AIPC 49-51-84-30-140 PACKING (3) with Synthetic base Lubricating Oil-Turbine Engine - - (Material No.03ABA1) or Synthetic base Lubricating Oil-Turbine Engine Low Temp. - (Material No.03ABB1) .
(3) Install the packings (2) and (3) on the transducer port (4).
(4) Remove the unwanted lubricant from the packings (2) and (3) and from the transducer port (4).
(5) Put the transducer port (4) into the APU.
(6) Tighten the nut (1).
(7) TORQUE the nut (1) to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )

.
(8) Remove the CAP-BLANKING from each electrical connector and receptacle.
(9) Connect the electrical connector (5) to the transducer port (4).

Subtask 49-51-16-865-055-A ** ON A/C NOT FOR ALL

B. Remove the safety clip(s) and the tag(s) and close 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 49-51-16-710-053-A ** ON A/C NOT FOR ALL

C. Do the ECB Self-Test (Ref. AMM TASK 49-00-00-710-009).
(1) Examine the differential pressure transducer (2) for air leaks (Ref. AMM TASK 49-00-00-790-006).

NOTE: No leaks are permitted.

5. Close-up
Subtask 49-51-16-410-052-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Set the LIGHT control SW 11LJ to the OFF position.
(3) Close the APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-410-001).
(4) Remove the access platform(s).

Subtask 49-51-16-860-055-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Put the related hydraulic system in the pressurized configuration (Ref. AMM TASK 29-00-00-864-001).
(2) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 01:30:53 UTC