W DOC AIRBUS | AMM A320F

Adjustment of the Reference CLOSED Position of the Variable Bleed Valve (VBV) System [CFMI]

TASK 75-31-00-820-002-A
Adjustment of the Reference CLOSED Position of the Variable Bleed Valve (VBV) System

1. Reason for the Job
You can do this procedure after each line-maintenance operation of these components:
  • VBV stop mechanism,
  • Flexible shafts,
  • Main flexible shaft,
  • Master bleed valve and ballscrew actuator,
  • VBV doors,
  • VBV position sensor.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific
AR
WARNING NOTICE(S)
856A2501
1
WRENCH-VBV MANUAL CONTROL
856A2664
1
GAGE, SETTING - VBV DOORS
856A3368
1
YOKE,SETTING-VBV DOORS
856A3408
1
GAGE - VBV DOOR SETTING YOKE
 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-A
Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-A
Closing of the Fan Cowl Doors
TASK 72-23-00-000-005-A
Removal of the Fan Duct Panels
TASK 72-23-00-400-005-A
Installation of the Fan Duct Panels
TASK 75-31-20-000-001-A
Removal of the Bleed Valve Stop Mechanism
TASK 75-31-20-400-001-A
Installation of the Bleed Valve Stop Mechanism
TASK 75-31-20-820-002-A
Set the Variable Bleed Valve Assembly to the Closed Position
TASK 75-31-30-000-003-A
Removal of a VBV Inter-connecting Flexible Shaft (Typical)
TASK 75-31-30-400-003-A
Installation of a VBV Inter-connecting Flexible Shaft (Typical)
TASK 78-30-00-081-041-A
Make the Thrust Reverser Serviceable after Maintenance
TASK 78-30-00-481-041-A
Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-36-00-010-040-A
Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-A
Closing of the Thrust Reverser Doors
F Adjustment of the Reference CLOSED Position of a VBV Doors (TYPICAL) with Tool Configuration One
F Adjustment of the Reference CLOSED Position of a VBV Door (TYPICAL) with tool Configuration 2
3. Job Set-up
Subtask 75-31-00-941-063-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 75-31-00-010-069-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 2M (6 FT) - ADJUSTABLE in position.
Subtask 75-31-00-040-058-A ** ON A/C NOT FOR ALL
C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).
Subtask 75-31-00-010-070-A ** ON A/C NOT FOR ALL
D. Get Access
   (1) Open the thrust reverser doors (Ref. AMM TASK 78-36-00-010-040):
     (a) FOR [1000EM1] (ENGINE-1)
451AL 452AR
     (b) FOR [1000EM2] (ENGINE-2)
461AL 462AR
   (2) If applicable, remove the fan duct panels (Ref. AMM TASK 72-23-00-000-005).
   (3) Set the VBV system to the reference CLOSED position (Ref. AMM TASK 75-31-20-820-002).
4. Procedure
Subtask 75-31-00-820-052-A ** ON A/C NOT FOR ALL
A. Adjustment of the Reference CLOSED Position of the VBV System

PRE SB 72-310

   (1) Adjust the reference CLOSED position of a VBV door (TYPICAL) with tool configuration One.
F Adjustment of the Reference CLOSED Position of a VBV Doors (TYPICAL) with Tool Configuration One ** ON A/C NOT FOR ALL
     (a) Disengage the flexible shafts ends from the VBV door sockets (Ref. AMM TASK 75-31-30-000-003).
     (b) Turn the flexible shaft socket of the ballscrew actuator by hand or with 856A2501 WRENCH-VBV MANUAL CONTROL (856A2501G01) to completely close the VBV door.
     (c) Make sure that the 856A3368 YOKE,SETTING-VBV DOORS (856A3368G04) is correctly set with the 856A3408 GAGE - VBV DOOR SETTING YOKE (856A3408G02).
     (d) Install the 856A3368 YOKE,SETTING-VBV DOORS (856A3368G04) as follows:
       1 Introduce the yoke trunnions in the reference holes of the VBV door.
       2 Attach the hook to the bleed valve casing.
     (e) Turn the flexible shaft socket to set the VBV door to the reference CLOSED position.
     (f) Continue to turn to cancel the gap between door and pusher, and between yoke ends and fan frame.
     (g) Install the flexible shafts (Ref. AMM TASK 75-31-30-400-003).
     (h) Make sure that the door is still in the reference CLOSED position, and remove the 856A3368 YOKE,SETTING-VBV DOORS (856A3368G04).
     (i) If necessary, use the same procedure to adjust the others VBV doors reference CLOSED position.
   (2) Adjust the reference CLOSED position of a VBV door (TYPICAL) with tool configuration 2.
F Adjustment of the Reference CLOSED Position of a VBV Door (TYPICAL) with tool Configuration 2 ** ON A/C NOT FOR ALL
     (a) Disengage the flexible shafts ends from the VBV door sockets (Ref. AMM TASK 75-31-30-000-003).
     (b) Turn the flexible shaft socket of the ballscrew actuator by hand or with 856A2501 WRENCH-VBV MANUAL CONTROL (856A251G01) to completely close the VBV door.
     (c) Install the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) as follows:
       1 Position the 2 locator fittings in the reference holes of the VBV door.
       2 Push tool against the flexible shaft socket.
NOTE: The tool yoke will not engage if the VBV door is fully closed.
     (d) Turn the flexible shaft socket to open the VBV door until the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) yoke engages on the flexible shaft socket.
     (e) Remove the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) after installation of the flexible shafts (Ref. AMM TASK 75-31-30-400-003).
     (f) If necessary, use the same procedure to adjust the other VBV doors reference CLOSED position.

POST SB 72-310

   (3) Adjust the reference CLOSED position of a VBV door (TYPICAL) with tool configuration 2.
F Adjustment of the Reference CLOSED Position of a VBV Door (TYPICAL) with tool Configuration 2 ** ON A/C NOT FOR ALL
     (a) Disengage the flexible shafts ends from the VBV door sockets (Ref. AMM TASK 75-31-30-000-003).
     (b) Turn the flexible shaft socket of the ballscrew actuator by hand or with 856A2501 WRENCH-VBV MANUAL CONTROL (856A2501G01) to completely close the VBV door.
     (c) Install the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) as follows:
       1 Position the 2 locator fittings in the reference holes of the VBV door.
       2 Push tool against the flexible shaft socket.
NOTE: The tool yoke will not engage if the VBV door is fully closed.
     (d) Turn the flexible shaft socket to open the VBV door until the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) yoke engages on the flexible shaft socket.
     (e) Remove the 856A2664 GAGE, SETTING - VBV DOORS (856A2664G01) after installation of the flexible shafts (Ref. AMM TASK 75-31-30-400-003).
     (f) If necessary, use the same procedure to adjust the other VBV doors reference CLOSED position.

END OF SB 72-310

   (4) Set the VBV stop mechanism to the CLOSED position as follows:
     (a) Disengage the flexible shafts ends from the master VBV door and ballscrew actuator (Ref. AMM TASK 75-31-30-000-003).
     (b) Put the master VBV door and ballscrew actuator to the reference CLOSED position with the 856A2501 WRENCH-VBV MANUAL CONTROL (856A2501G01).
     (c) Make sure that the master VBV door and ballscrew actuator reference CLOSED position is correct.
     (d) If the reference CLOSED position is not correct, adjust the stop mechanism reference CLOSED position as follows:
       1 Remove the VBV stop mechanism (Ref. AMM TASK 75-31-20-000-001).
       2 Set the master VBV door and ballscrew actuator to the reference CLOSED position (Ref. 4.A.(1), 4.A.(2), 4.A.(3)).
       3 Set the stop mechanism to the CLOSED position and install it (Ref. AMM TASK 75-31-20-400-001).
     (e) Install the flexible shafts (Ref. AMM TASK 75-31-30-400-003).
5. Close-up
Subtask 75-31-00-410-070-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) If necessary, install the fan duct panels (Ref. AMM TASK 72-23-00-400-005).
   (3) 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 75-31-00-440-058-A ** ON A/C NOT FOR ALL
B. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041).
Subtask 75-31-00-410-071-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] 2026.04.02 07:39:57 UTC
"WTRUIB" 2025