Set the Variable Bleed Valve Assembly to the Closed position [CFMB]

TASK 75-31-20-820-001-A
Set the Variable Bleed Valve Assembly to the Closed position

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	WARNING NOTICE(S)
856A2501	1	WRENCH-VBV MANUAL CONTROL

B. Work Zones and Access Panels

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

C. 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 72-23-00-000-027-A	Removal of the Fan Duct Panels
TASK 72-23-00-400-027-A	Installation of the Fan Duct Panels
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 78-36-00-010-040-B	Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-B	Closing of the Thrust Reverser Doors
Setting of the VBV System to the Closed Position

3. Job Set-up
Subtask 75-31-20-941-053-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 75-31-20-010-058-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open 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

Subtask 75-31-20-040-051-A ** ON A/C NOT FOR ALL

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

Subtask 75-31-20-010-059-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser doors: (Ref. AMM TASK 78-36-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR

4. Procedure
Subtask 75-31-20-010-060-A ** ON A/C NOT FOR ALL

A. Remove the fan duct panel between struts No.3 and No.4 (panel at the 2:30 o'clock position) or the fan duct panel between struts No.4 and No.5 (panel at the 3:30 o'clock position) (Ref. AMM TASK 72-23-00-000-027).

Subtask 75-31-20-820-051-A ** ON A/C NOT FOR ALL

B. Set the VBV doors to the Closed position. Use 856A2501 WRENCH-VBV MANUAL CONTROL (856A2501G01) at 2:30 or at 3:30 o'clock to do this.

Subtask 75-31-20-410-058-A ** ON A/C NOT FOR ALL

C. Install the fan duct panels at the 2:30 or 3:30 o'clock (Ref. AMM TASK 72-23-00-400-027).

5. Close-up
Subtask 75-31-20-410-059-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 thrust reverser cowl doors: (Ref. AMM TASK 78-36-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(b) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 75-31-20-440-051-A ** ON A/C NOT FOR ALL

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

Subtask 75-31-20-410-060-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).

[Rev.10 from 2021] 2026.04.01 03:10:36 UTC