Visual Inspection of the Variable Bleed Valve (VBV) System [CFMB]

TASK 75-31-00-210-002-A
Visual Inspection of the Variable Bleed Valve (VBV) System

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)

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 75-31-30-200-002-A	Visual Inspection of the VBV Main Flexible Shaft and the VBV Inter-connecting Flexible Shafts
TASK 75-31-50-000-002-A	Removal of the Bleed Valve and Master Ballscrew Actuator Assembly
TASK 75-31-50-400-002-A	Installation of the Bleed Valve and Master Ballscrew Actuator Assembly
TASK 75-31-60-000-002-A	Removal of the Bleed Valve and Ballscrew Actuator Assembly
TASK 75-31-60-400-002-A	Installation of the Bleed Valve and Ballscrew Actuator Assembly
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
Visual Inspection of the VBV System

3. Job Set-up
Subtask 75-31-00-941-057-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Put a WARNING NOTICE(S) in position to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than five 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) in position to tell persons not to energize FADEC 1(2).

Subtask 75-31-00-010-055-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 the ACCESS PLATFORM 1M(3 FT) in position.

Subtask 75-31-00-040-052-A ** ON A/C NOT FOR ALL

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

Subtask 75-31-00-010-058-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 75-31-00-010-068-A ** ON A/C NOT FOR ALL

A. Remove the fan duct panels (Ref. AMM TASK 72-23-00-000-027).

Subtask 75-31-00-210-051-A ** ON A/C NOT FOR ALL

B. Visually Inspect the following:

INSPECT/CHECK	MAXIMUM SERVICEABLE LIMITS	REMARKS
1.The bleed valve doors for:
A.Distortion	Not serviceable	Replace the bleed valve (Ref. AMM TASK 75-31-60-000-002) and (Ref. AMM TASK 75-31-60-400-002).
B.Damaged seal	Serviceable, if the engine parameters are within limits	Replace the bleed valve (Ref. AMM TASK 75-31-60-000-002) and (Ref. AMM TASK 75-31-60-400-002).
2.The master VBV door for:
A.Distortion	Not serviceable	Replace the master VBV door (Ref. AMM TASK 75-31-50-000-002) and (Ref. AMM TASK 75-31-50-400-002).
B.Damaged seal	Serviceable, if the engine parameters are within limits	Replace the master VBV door (Ref. AMM TASK 75-31-50-000-002) and (Ref. AMM TASK 75-31-50-400-002).
3.The flexible shafts Do a visual inspection (Ref. AMM TASK 75-31-30-200-002).

Subtask 75-31-00-410-068-A ** ON A/C NOT FOR ALL

C. Install the fan duct panels (Ref. AMM TASK 72-23-00-400-027).

5. Close-up
Subtask 75-31-00-410-055-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 75-31-00-440-052-A ** ON A/C NOT FOR ALL

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

Subtask 75-31-00-410-058-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 access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:10:28 UTC