Installation of the Beam Electrical Harness [CFMB]

TASK 78-31-17-400-002-A
Installation of the Beam Electrical Harness

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: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 400
FIN: 4103KS1 ** ON A/C NOT FOR ALL
FIN: 4103KS2 ** 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	PLIERS - NOSE, SOFT, LONG
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 45 and 35 lbf.in (0.51 and 0.40 m.daN )
No specific	Torque wrench: range to between 80 and 70 lbf.in (0.90 and 0.79 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.CP2318)	sealant MC-780 B2

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

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 78-31-00-710-042-A	Operational Test of the Thrust Reverser System
TASK 78-36-00-010-040-B	Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-B	Closing of the Thrust Reverser Doors
Blocker Door Switch, Actuation Levers and Beam Electrical Harness

3. Job Set-up
Subtask 78-31-17-860-054-A ** ON A/C NOT FOR ALL

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

Subtask 78-31-17-010-058-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Make sure that the fan cowl doors are open (Ref. AMM TASK 71-13-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Make sure that the thrust reverser doors are open (Ref. AMM TASK 78-36-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 78-31-17-040-055-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 78-31-17-420-051-A ** ON A/C NOT FOR ALL

A. Installation of the Beam Electrical Harness
(1) Apply a layer of the sealant MC-780 B2 (Material No.CP2318) on the harness flange surface that will touch the forward frame.
(2) Install the beam electrical harness (130) through the hole in the forward frame.
(3) Connect the beam electrical harness (130) to the blocker door deploy-switch (110).
(4) Tighten the coupling nut of the deploy switch connector (120) with the PLIERS - NOSE, SOFT, LONG.
(5) Attach the beam electrical harness (130) to the forward frame with the three bolts (150).
(6) TORQUE the bolts (150) to between 80 and 70 lbf.in (0.90 and 0.79 m.daN )

.
(7) Connect the forward frame electrical-harness to the beam electrical harness (130).
(8) Attach the deploy-switch access door (70) with the three screws (80).
(9) TORQUE the screws (80) to between 45 and 35 lbf.in (0.51 and 0.40 m.daN )

5. Close-up
Subtask 78-31-17-410-051-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) Close the thrust reverser doors (Ref. AMM TASK 78-36-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 78-31-17-440-051-A ** ON A/C NOT FOR ALL

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

Subtask 78-31-17-410-052-A ** ON A/C NOT FOR ALL

C. Close Access
(1) 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
(2) Remove the WARNING NOTICE(S).
(3) Remove the access platform(s).

Subtask 78-31-17-710-051-A ** ON A/C NOT FOR ALL

D. Do an operational test of the thrust reverser system (Ref. AMM TASK 78-31-00-710-042).

[Rev.10 from 2021] 2026.04.01 13:11:42 UTC