AIR -COMPRESSOR BLEED CONTROL -GENERAL DESCRIPTION
EFFECTIVITY BEJ ALL 75-32-00
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D633W101-BEJ Sep 05/2002
AIR -COMPRESSOR BLEED CONTROL -2.5 BLEED VALVE ACTUATOR
Purpose The 2.5 bleed valve actuator moves the bleed valve to control the airflow from the LPC to the HPC. After replacement of the 2.5 bleed valve actuator, you must do a hydraulic adjustment of the actuator. You need an external hydraulic pump for adjustment of the actuator.
Location
The actuator is on the intermediate case at the 7:00 position.
Functional Description
The EEC sends a torque motor signal to the actuator. This lets servo fuel move the actuator piston.
If a fuel seal leak occurs, a drain tube sends the fuel to the engine/strut overboard drains.
Training Information Point
You must remove the fan exit liner segment below the actuator before you remove the actuator.
When you remove the 2.5 bleed valve actuator, make sure to count the number of turns required to bottom the piston shaft. Make a record of the number of turns.
When you install the 2.5 bleed valve actuator, make sure that you fully engage (turn clockwise) the piston shaft. Then turn the piston shaft counterclockwise the number of turns you recorded at actuator removal.
EFFECTIVITY BEJ ALL 75-32-00
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D633W101-BEJ Sep 05/2002
AIR -COMPRESSOR BLEED CONTROL -2.5 BLEED VALVE ACTUATOR
EFFECTIVITY BEJ ALL 75-32-00
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D633W101-BEJ Sep 05/2002
AIR -COMPRESSOR BLEED CONTROL -2.9 BLEED VALVE SOLENOID AND PNEUMATIC RELAY VALVE
Purpose
The 2.9 (start/stability) bleed valve solenoid controls the supply of PS3 servo air to the two 2.9 bleed valves. The 2.9 (start/ stability) pneumatic relay valve bleeds air from the 2.9 stability bleed valve to let it open.
Location
The bleed valve solenoid is on the intermediate case at the
11:00 position. The pneumatic relay valve is on the right side of the bleed valve solenoid.
2.9 (Start/Stability) Bleed Valve Solenoid
There are two solenoids in a common housing. Each solenoid has two coils. A solenoid controls the filtered PS3 servo air to a
2.9 bleed valve.
One solenoid controls servo air to the 2.9 start bleed valve. The other solenoid controls the servo air to the pneumatic relay valve.
2.9 (Start/Stability) Pneumatic Relay Valve
The relay valve lets the filtered PS3 servo air close the 2.9 stability bleed valve. If there is a surge, it also quickly bleeds PS3 servo air to open the bleed valve.
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