(a)  
Slowly decrease the test bench pressure to 1200 psig.

 (b)  
Write down the test bench pressure when the SYS FAULT light comes on (_______PSIG). 1) Make sure the SYS FAULT light comes on between 1200-1300

 psig. 2) Make sure the HYD PRESS SYS 1, 2, 3, or 4 shows on the primary EICAS screen when the SYS FAULT light comes on.
 3)  Make sure these displays go off the EICAS screen when the SYS FAULT light comes on: a) HYD PRESS ENG 1, 2, 3, or 4
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 29-31-00
 ALL  ú ú 01 Page 508 ú Oct 10/91
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 b) HYD PRESS DEM 1, 2, 3, or 4. 4) Make sure the MASTER CAUTION light comes on and you hear an alarm when the SYS FAULT light comes on.
 S 865-035
 (31)
 Decrease the test bench pressure to 0 psig.

 (a)  
Make sure the system pressure indication on the EICAS screen decreases to 0 - 160 psig.

 NOTE: You can operate the rudder to decrease the system
____
 pressure faster.

 S 085-058
 (32)
 Disconnect the test bench:

 (a)  
Disconnect the test bench hose from the EDP pressure hose.

 (b)  
Connect the airplane pressure hose to the EDP
 (AMM 29-11-05/401).

 S 485-059
 (33)
 Connect the test bench:

 (a)  
Disconnect the hose at the pressure port on the demand pump for the applicable system (AMM 29-11-17/401 or AMM 29-11-19/401, as applicable).

 (b)  
Connect the pressure hose from the test bench to the pressure hose for the system demand pump.

 S 785-039
 (34)
 Do these steps while you monitor the test bench pressure and the EICAS display:

 (a)  
Slowly increase the test bench pressure to 1350 psig.

 (b)  
Stop until the HYD PRESS DEM 1, 2, 3, or 4 display shows on the primary EICAS screen.

 S 785-040
 (35)
 Do these steps while you monitor the PRESS light for the demand pump and the test bench pressure:

 (a)  
Slowly increase the test bench pressure to 1600 psig.

 (b)  
Write down the test bench pressure when the PRESS light for the demand pump goes off (_______PSIG). 1) Make sure the PRESS light for the demand pump goes off

 between 1400-1600 psig. 2) Make sure the HYD PRESS DEM 1, 2, 3, or 4 EICAS message goes off when the demand pump PRESS light goes off.
 S 785-041
 (36)
 Do these steps while you monitor the PRESS light for the demand pump and the EICAS display:

 (a)  
Slowly decrease the test bench pressure to 1400 psig.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 29-31-00
 ALL  ú ú 01 Page 509 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 (b)  Write down the test bench pressure when the PRESS light for the demand pump comes on (_______PSIG). 1) Make sure the PRESS light for the demand pump comes on
 between 1400-1600 psig.
 2)  Make sure the HYD PRESS DEM 1, 2, 3, or 4 display shows on the primary EICAS screen when the PRESS light for the demand pump comes on.
 S 865-042
 (37)
 Decrease the test bench pressure to 0 psig.

 (a)  
Make sure the system pressure on the EICAS display decreases to 0 - 160 psig.

 NOTE: You can operate the rudder to decrease the system
____
 pressure faster.

 S 085-043
 (38)
 Turn off the hydraulic test bench.

 S 085-060

 (39)
 Disconnect the hydraulic test bench:

 (a)  
Disconnect the test bench hoses.

 (b)  
Connect the airplane pressure hose to the demand pump (AMM 29-11-17/401 or AMM 29-11-19/401, as applicable).

 S 615-045
 (40)
 Fill (or drain) the hydraulic reservoir to the correct level (AMM 12-12-01/301).
　
中國航空網 m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機維護手冊 液壓 HYDRAULIC 2(111)