screw clockwise to increase the pressure. 3) If the outlet pressure is too high, turn the adjustment
 screw counterclockwise to decrease the pressure. 4) Tighten the adjustment screw locknut. 5) Do the above test steps again until the differential
 pressure regulator is correctly adjusted.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 49-52-21
 ALL  ú ú 01 Page 503 ú Mar 15/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES/MAINTENANCE MANUAL ////////////////////////
S 085-005
 (5)  Remove the test pressure gage:
 (a)  Disconnect the flexible air line from the pressure gage and the
 T-fitting on the bleed air valve.
 (b)  Install the cap on the T-fitting port.
 S 415-006
 (6)  Close the APU cowl door:
 (a)  Disconnect the door support rods.
 (b)  Put the door support rods in the clips on the APU cowl door.
 (c)  Close the APU cowl door.
 (d)  Close the latches on the APU cowl door.
 S 865-007
 (7)  Set the circuit breaker and the switch:
 (a)  Remove the DO-NOT-CLOSE tag and close this circuit breaker:
 1)  E3-3 Electrical Shelf, APU Control Unit
 (b)  Remove the DO-NOT-OPERATE tag from the APU master switch on the
 P5 forward overhead panel.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 49-52-21
 ALL  ú ú 01 Page 504 ú Jul 15/91
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
PROPORTIONAL CONTROL VALVE - REMOVAL/INSTALLATION
_________________________________________________
 1.  General_______
 A.  This procedure contains the removal and the installation tasks for the proportional control valve (PCV).
 B.  The PCV is on the bottom right side of the APU, above the ignition unit. You can get access to the valve through the APU cowl door.
 TASK 49-52-31-004-001
 2.  Proportional Control Valve (PCV) Removal (Fig. 401)________________________________________
 A.  Access
 (1)  
Location Zones
 101 Control Cabin, LH
 205 Electronic Compartment
 703 APU Compartment

 (2)  
Access Panels
 1201 Electronic Equipment Access Door
 3804 APU Cowl Door

 B.  Procedure
 S 864-002
 (1)  Set the switch and the circuit breaker:
 (a)  
Set the APU master switch, on the P5 forward overhead panel, to the OFF position and attach a DO-NOT-OPERATE tag.

 (b)  
Open this circuit breaker and attach a DO-NOT-CLOSE tag: 1) E3-3 Electrical Shelf, APU Control Unit

 S 014-003
 (2)  Open the APU cowl door:
 (a)  
Open the latches for the APU cowl door.

 (b)  
Open the APU cowl door.

 (c)  
Connect the door support rods.

 S 014-004
 CAUTION:_______BE CAREFUL WHEN YOU MOVE THE LOWER SHROUD. DAMAGE TO THE SHROUD DRAIN LINES CAN OCCUR.
 (3)  Remove the lower shroud:
 (a) Hold the lower shroud and open the shroud latches.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES WITH ETC ú

 49-52-31
 ú ú 01 Page 401 ú Jul 15/95
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / GTCP85-129 SERIES /737-300/400/500/ ENGINES /MAINTENANCE MANUAL ////////////////////////
SEE A
ELECTRICAL
CONNECTOR
BOLT WASHER (2 LOCATIONS)
PROPORTIONAL
CONTROL
VALVE (PCV)

CONTROL
AIR LINE A
Proportional Control Valve Installation Figure 401
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES WITH ETC ú
　
中國(guó)航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：737-300 400 500 AMM 飛機(jī)維護(hù)手冊(cè) AIRBORNE AUXILIARY POWER 2(86)