Removal of the Lower Blocker Door [CFMB]

TASK 78-32-41-000-001-A
Removal of the Lower Blocker Door

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	DRIFT - COPPER, SOFT
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 78-30-00-481-041-B	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-32-41-860-001-A	Manual Deployment of the Blocker Door
Lower Blocker Door
Hydraulic Actuator
Deploy-Switch Access Door

3. Job Set-up
Subtask 78-32-41-941-055-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) 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) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 78-32-41-010-055-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 78-32-41-040-055-A ** ON A/C NOT FOR ALL

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

4. Procedure
Subtask 78-32-41-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Lower Blocker Door
(1) Remove the lower access door:

Lower Blocker Door ** ON A/C NOT FOR ALL

(a) Remove the bolt that attach the lower access door.
(b) Remove the access door from the thrust reverser.
(2) Remove the access door of the hydraulic actuator clevis.

Hydraulic Actuator ** ON A/C NOT FOR ALL

(a) Remove the three screws which attach the access door to the blocker door.
(b) Remove the access door from the blocker door.
(3) Remove the hydraulic actuator clevis from the blocker door:

Hydraulic Actuator ** ON A/C NOT FOR ALL

(a) Remove the four bolts and washers which attach the clevis on the blocker door.
(b) Remove the clevis.
(4) Remove the deploy-switch access door:

Deploy-Switch Access Door ** ON A/C NOT FOR ALL

(a) Remove the three screws.
(b) Remove the access door.
(5) Remove the lower blocker door.

CAUTION: HOLD ACTUATOR ROD WHEN YOU MANUALLY DEPLOY BLOCKER DOOR TO AVOID DAMAGE TO MATERIAL.

(a) Manually open the lower blocker door with the hydraulic actuator locked (Ref. AMM TASK 78-32-41-860-001).
(b) Remove the screws which attach the pivot access doors.

Lower Blocker Door ** ON A/C NOT FOR ALL

(c) Remove the two pivot access doors from the blocker door.
(d) Remove the bolts, washers and the contact finger.
(e) Remove and discard cotter pins (10) and (20).
(f) Remove the castellated nuts and washers.
(g) Remove two pivot bolts:

WARNING: KEEP THE BLOCKER DOOR IN THE OPEN POSITION IN ORDER NOT TO DAMAGE MATERIAL OR INJURE PERSONNEL.

1 Remove the two pivot bolts from the blocker door with a DRIFT - COPPER, SOFT.
2 Remove the blocker door.

[Rev.10 from 2021] 2026.04.01 13:11:41 UTC