Installation of the Engine 1 Hydraulic Low-Pressure Switch Tube

TASK 29-11-49-400-044-A
Installation of the Engine 1 Hydraulic Low-Pressure Switch Tube

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

WARNING: DO NOT TOUCH THE HYDRAULIC SYSTEM COMPONENTS FOR A SHORT TIME AFTER THE ENGINE IS SHUTDOWN. THE ENGINE COMPONENTS STAY HOT FOR SOME TIME AND CAN CAUSE INJURY.

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	AR	CONTAINER 5 L (1.32 USGAL)
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 405 and 380 lbf.in (4.58 and 4.29 m.daN )

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL

C. Referenced Information

REFERENCE	DESIGNATION
TASK 29-10-00-864-001-A	Depressurize the Green Hydraulic System
TASK 29-11-00-710-001-A	Operational Test of the Green Hydraulic System
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
Hydraulic Low Pressure Switch Tube
FOR [1000EM1] (ENGINE-1)
TASK 71-13-00-010-040-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-A	Closing of the Fan Cowl Doors

3. Job Set-up
Subtask 29-11-49-860-072-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Make sure that the Green hydraulic system is depressurized (Ref. AMM TASK 29-10-00-864-001).
(2) Make sure that the Green hydraulic reservoir is depressurized (Ref. AMM TASK 29-14-00-614-001).
(3) Make sure that the WARNING NOTICE(S) is (are) in position to tell persons not to pressurize the Green hydraulic system:

on the ground service panel 197CB.

(4) Make sure that the WARNING NOTICE(S) is (are) in position on the access door 195BB to tell persons not to pressurize the Green hydraulic reservoir.

Subtask 29-11-49-941-078-A ** ON A/C NOT FOR ALL

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

make sure that the WARNING NOTICE(S) is (are) 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) Make sure that the WARNING NOTICE(S) is (are) in position to tell persons not to pressurize the Green hydraulic system:

in the cockpit, on the HYD section of the overhead panel 40VU.

(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) Make sure that the WARNING NOTICE(S) is (are) in position to tell persons not to energize the FADEC 1(2).
(6) Make sure that a CONTAINER 5 L (1.32 USGAL) is below the suction-hose adapter connection to the hydraulic pump.

Subtask 29-11-49-010-079-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Make sure that the left fan-cowl door is open:
(a) FOR [1000EM1] (ENGINE-1)
make sure that the door 437AL is open (Ref. AMM TASK 71-13-00-010-040).
(2) Make sure that the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE is in position at the engine.

4. Procedure
Subtask 29-11-49-420-064-A ** ON A/C NOT FOR ALL

A. Installation of the Hydraulic Low-Pressure Switch Tube
(1) Remove the protective covers from the hydraulic low-pressure switch tube (5), the fitting on the pressure hose/tube, and the hydraulic low-pressure switch.
(2) Loosely connect the low pressure switch tube (5) to the pressure hose/tube.
(3) Loosely connect the low-pressure switch tube (15) to the hydraulic low-pressure switch.
(4) Make sure that the low-pressure switch tube (5) is in the correct position on the engine.
(5) TORQUE the coupling nuts on the low-pressure switch tube (5) to between 405 and 380 lbf.in (4.58 and 4.29 m.daN )

NOTE: Use a second wrench to hold the tee fitting and the pressure switch when you torque the coupling nuts.

Subtask 29-11-49-710-057-A ** ON A/C NOT FOR ALL

B. Operational Test
(1) Do an operational test of the Green hydraulic system (Ref. AMM TASK 29-11-00-710-001).
(2) During the dry motoring, make sure that there are no leaks from the low-pressure switch tube.

5. Close-up
Subtask 29-11-49-860-073-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Remove the access platform(s).
(2) Make sure that the work area is clean and clear of tools and other items.

Subtask 29-11-49-410-057-A ** ON A/C NOT FOR ALL

B. Close Access
(1) Close the left fan-cowl door:
(a) FOR [1000EM1] (ENGINE-1)
Close the door 437AL (Ref. AMM TASK 71-13-00-410-040).
(2) Close the door 195BB.

Subtask 29-11-49-942-059-A ** ON A/C NOT FOR ALL

C. Safety Precautions
(1) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 00:16:51 UTC