Removal of the Differential Pressure Indicator (DPI)

TASK 29-11-43-000-011-A
Removal of the Differential Pressure Indicator (DPI)

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: DO NOT GET HYDRAULIC FLUID ON YOUR SKIN, IN YOUR EYES OR IN YOUR MOUTH. HYDRAULIC FLUID IS POISONOUS AND CAN GO THROUGH YOUR SKIN AND INTO YOUR BODY. FLUSH HYDRAULIC FLUID FROM YOUR EYES, MOUTH OR SKIN WITH WATER. GET MEDICAL AID IF YOU GET HYDRAULIC FLUID IN YOUR EYES OR MOUTH.

CAUTION: DO NOT LET HYDRAULIC FLUID FALL ON THE ENGINE. UNWANTED HYDRAULIC FLUID MUST BE REMOVED IMMEDIATELY WITH A CLEAN LINT FREE CLOTH. THE FLUID CAN CAUSE DAMAGE TO THE SURFACE PROTECTION AND TO SOME PARTS.

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	1	CAP - BLANKING, HYDRAULIC
No specific	AR	CONTAINER 5 L (1.32 USGAL)
No specific	1	COVER - BLANKING, HYDRAULIC RESISTANT
No specific	1	PLUG - BLANKING
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
195BB, 197CB
FOR [1000EM1] (ENGINE-1)
437AL, 438AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 29-10-00-864-001-A	Depressurize the Green Hydraulic System
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
Differential Pressure Indicator (DPI)
FOR [1000EM1] (ENGINE-1)
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)

3. Job Set-up
Subtask 29-11-43-860-063-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Depressurize the Green hydraulic system (Ref. AMM TASK 29-10-00-864-001).
(2) Depressurize the Green hydraulic reservoir (Ref. AMM TASK 29-14-00-614-001).
(3) On the ground service panel 197CB:

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

(4) On the access door 195BB:

Put WARNING NOTICE(S) in position to tell persons not to pressurize the Green hydraulic reservoir.

Subtask 29-11-43-941-066-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:

Put WARNING NOTICE(S) in position to tell persons not to start the engine.

(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) In the cockpit, on the HYD section of the overhead panel 40VU:

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

(4) On the overhead maintenance panel 50VU:

Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.

(5) Put WARNING NOTICE(S) in position to tell persons not to energize the FADEC 1(2).
(6) Put a clean CONTAINER 5 L (1.32 USGAL) in position below the DPI.

Subtask 29-11-43-010-058-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the fan cowls:
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR (Ref. AMM TASK 71-13-00-010-010).
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at the engine.

4. Procedure
Subtask 29-11-43-020-060-A ** ON A/C NOT FOR ALL

A. Removal of the DPI
(1) Remove the lockwire from the DPI (2) and the head (1).
(2) Remove the DPI (2) from the head (1).

NOTE: Do not disassemble the DPI (2).

(3) Remove the spring (5):

CAUTION: THE DIFFERENTIAL PRESSURE INDICATOR (DPI) AND SPRING ARE A MATCHED PAIR.

(a) Remove the spring (5) that is in the head (1).
(4) Remove and discard the packings (4) and (6), and the retainer (3).

CAUTION: DO NOT USE SOLVENTS TO CLEAN THE DIFFERENTIAL PRESSURE INDICATOR (DPI).

(5) Clean the DPI (2) with dry clean air.

Subtask 29-11-43-620-051-A ** ON A/C NOT FOR ALL

B. Install the applicable COVER - BLANKING, HYDRAULIC RESISTANT / CAP - BLANKING, HYDRAULIC / PLUG - BLANKING on all the openings.

[Rev.10 from 2021] 2026.04.01 07:54:12 UTC