S 213-137
(25)
Make sure the OF, RF, or LO indication does not show on the EICAS maintenance page adjacent to the HYD QTY (1, 2, 3, 4).
S 213-093
(26)
Make sure the system 2 quantity, which shows on the EICAS, does not drop below 0.80, and the system 4 quantity, which shows on the EICAS, does not go above 1.10.
S 863-094
(27)
Remove the hydraulic power if it is not necessary (AMM 29-11-00/201).
S 863-095
(28)
Remove the electrical power if it is not necessary (AMM 24-22-00/201).
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
12-12-01
ALL ú ú 01 Page 313 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
S 983-088
(29) Procedure 6 (Transfer fluid from system 4 to system 2).
(a) Release the parking brake.
(b) Remove the pressure from hydraulic system 1 (AMM 29-11-00/201).
(c) Pressurize hydraulic system 4 to 3000 psi (AMM 29-11-00/201).
(d) Set the parking brake.
(e) Pressurize hydraulic system 2 to 3000 psi (AMM 29-11-00/201).
(f) Remove the pressure from hydraulic system 4 (AMM 29-11-00/201).
(g) Let the pressure in hydraulic system 4, which shows on the
EICAS, decrease to 1000 psi.
NOTE:____ You can operate the flight controls to release the
pressure faster.
(h) Release the parking brake.
(i) Repeat steps (b) through (h) until the HYD QTY on the EICAS
display shows .80 to 1.10 or the reservoir fill gauge is in the
green band.
NOTE:____ Approximately 68 cubic inches, 0.3 US Gallons should
be transfered each time the sequence is repeated.
S 213-138
(30)
Make sure the OF, RF, or LO indication does not show on the EICAS maintenance page adjacent to the HYD QTY (1, 2, 3, 4).
S 213-089
(31)
Make sure the system 4 quantity, which shows on the EICAS, does not drop below 0.80, and the system 2 quantity, which shows on the EICAS, does not go above 1.10.
S 863-090
(32)
Remove the hydraulic power if it is not necessary (AMM 29-11-00/201).
S 863-091
(33)
Remove the electrical power if it is not necessary (AMM 24-22-00/201).
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
12-12-01
ALL ú ú 01 Page 314 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
NOSE RADOME HINGE SNUBBER - SERVICING
_____________________________________
1. General_______
A. Two rotary hydraulic snubbers are attached to the nose radome hinges.
B. When the radome is opened or closed the hinges turn. The movement is transmitted to the nose radome snubbers by an input shaft. This movement is changed to linear movement by a pinion gear and a rack gear. The rack gear transmits movement to a piston located in the nose radome snubber. The piston moves hydraulic fluid from one internal area to a different area, in the snubber, through an adjustable opening.
C. High pressure in the nose radome snubber can cause hydraulic fluid leakage. This leakage makes regular hydraulic service necessary.
D. To service the nose radome snubber these operations are necessary:
-Open the nose radome
-Fill the nose radome snubber
-Remove air from the nose radome snubber
-Close the nose radome.
TASK 12-12-03-613-001
2. Service Nose Radome Hinge Snubber (Fig. 301)_________________________________
A. Standard Tools and Equipment
(1) A hydraulic pressure source filled with MIL-H-5606 fluid, which can supply 95 (|5) psi. The pressure source must have a male fitting which is threaded 7/16-20 UNF-3A.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 SERVICING 1(41)
