Installation of the Return Pipe of the Right Latch [CFMB]

TASK 78-31-49-400-046-A
Installation of the Return Pipe of the Right Latch

WARNING: WEAR A FACE SHIELD WHICH IS RESISTANT TO HIGH PRESSURE JETS WHEN YOU WORK ON PRESSURIZED SYSTEMS.

WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:

FLUSH IT AWAY WITH CLEAN WATER
GET MEDICAL AID.

CAUTION: USE TWO WRENCHES TO REMOVE OR INSTALL THE TUBE COUPLING NUTS:

ONE WRENCH TO HOLD THE UNION, AND
ONE TO LOOSEN OR TIGHTEN THE COUPLING NUT.

THIS PREVENTS DAMAGE TO THE PARTS.

FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 30 and 27 lbf.in (0.34 and 0.31 m.daN )
No specific	Torque wrench: range to between 125 and 113 lbf.in (1.41 and 1.28 m.daN )
No specific	Torque wrench: range to between 150 and 130 lbf.in (1.70 and 1.47 m.daN )
No specific	Torque wrench: range to between 300 and 260 lbf.in (3.39 and 2.94 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2245)	finish paint EA4 blue 5991

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-B	Closing of the Fan Cowl Doors
TASK 78-30-00-081-041-B	Make the Thrust Reverser Serviceable after Maintenance
TASK 78-30-00-481-041-B	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-30-00-710-040-B	Thrust Reverser Hydraulic System Bleed Procedure
Return Pipe of the Right Latch
Thermal Blankets on the Blocker Door Latches

3. Job Set-up
Subtask 78-31-49-860-087-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.

Subtask 78-31-49-010-144-A ** ON A/C NOT FOR ALL

B. Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR

Subtask 78-31-49-040-134-A ** ON A/C NOT FOR ALL

C. Make sure that the thrust reverser is unserviceable (Ref. AMM TASK 78-30-00-481-041).

4. Procedure
Subtask 78-31-49-420-078-A ** ON A/C NOT FOR ALL

A. Installation of the Return Pipe of the Right Latch
(1) Remove the protective covers from the pipe ends.
(2) Put the return pipe in position on the forward frame.
(3) Attach the return pipe to the interface bracket with the nut.
(4) Connect the coupling nut on opposite end of return pipe to the upper latch.
(5) TORQUE the nut to between 300 and 260 lbf.in (3.39 and 2.94 m.daN )

at the interface bracket.
(6) TORQUE the coupling nut to between 150 and 130 lbf.in (1.70 and 1.47 m.daN )

at the upper latch.

NOTE: A clearance of 0.15 in to 0.23 in (4 mm to 6 mm) is required between the HCU heatshield and the Return Pipe of the Right Latch.

(7) Connect the interface hydraulic hose to the return pipe.
(8) TORQUE the coupling nut to between 125 and 113 lbf.in (1.41 and 1.28 m.daN )

.
(9) Attach the flange and the upper half clamp to the upper hydraulic line bracket with the bolts and the nuts.
(10) TORQUE the bolts to between 30 and 27 lbf.in (0.34 and 0.31 m.daN )

NOTE: Apply a witness line of finish paint EA4 blue 5991 (Material No.CP2245) on all nuts and connections after they are torqued.

(11) Put the thermal blanket on the blocker door latch. Turn the Dzus fastener on the blanket 1/4 turn to lock it.

Thermal Blankets on the Blocker Door Latches ** ON A/C NOT FOR ALL

5. Close-up
Subtask 78-31-49-440-082-A ** ON A/C NOT FOR ALL

A. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041).

Subtask 78-31-49-410-091-A ** ON A/C NOT FOR ALL

B. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors: (Ref. AMM TASK 71-13-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

Subtask 78-31-49-710-072-A ** ON A/C NOT FOR ALL

C. Bleed the air from the thrust reverser hydraulic system. (Ref. AMM TASK 78-30-00-710-040)

[Rev.10 from 2021] 2026.04.01 13:11:49 UTC