A. Skydrol Assembly Lube - MCS 352 or Fire Resistant Hydraulic Fluid - BMS 3-11
3. Remove Hydraulic Pressure Transmitter
A. Depressurize hydraulic reservoir system. Refer to 29-09-300, Hydraulic Reservoir
Pressurization System - MP.
B. Depressurize applicable hydraulic system. Refer to 29-11-0, Hydraulic System A or 29-12-0, Hydraulic System B - MP.
C. Open SYSTEM A-B PRESSURE circuit breaker on P6 load control panel.
D. Remove connector plug from transmitter.
E. Disconnect hydraulic line to transmitter from modular unit (Fig. 401).
F. Remove transmitter mounting bolts and U-clamp and remove transmitter.
4. Install Hydraulic Pressure Transmitter
A. Install O-ring and union in transmitter pressure port. Apply assembly lube or hydraulic fluid to 0-ring and to threads of union.
B. Place U-clamp on transmitter, position over mounting holes in bulkhead stringer, and install mounting bolts (Fig. 401).
C. Connect hydraulic line from modular unit to transmitter.
D. Connect electrical connector to transmitter.
E. Close SYSTEM A-B PRESSURE circuit breaker on P6 load control panel.
F. Pressurize applicable hydraulic system and check for leaks (Ref. 29-11-0 or 29-12-0).
May 01/99 29-31-11 Page 401 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
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Hydraulic Pressure Transmitter Installation 500
29-31-11 Figure 401 May 01/98
Page 402
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
HYDRAULIC BRAKE PRESSURE TRANSMITTERS - REMOVAL/INSTALLATION
1. General
A. The pressure transmitters for the hydraulic brake system are similar units having the same removal and installation procedures, therefore, only one procedure will be given. Both transmitters are mounted on the aft wheel well bulkhead. The transmitters are accessible through the left and right wheel wells (Fig. 401).
2. Equipment and Materials
A. Skydrol Assembly Lube - MCS 352 or Fire Resistant Hydraulic Fluid - BMS 3-11
3. Remove Hydraulic Brake Pressure Transmitter
A. Depressurize applicable hydraulic system (Ref 29-11-0, Hydraulic System A or 29-12-0, Hydraulic System B - MP).
B. Depressurize brake accumulator by applying brakes fully six times.
C. Open BRAKE-PRESS IND circuit breaker on P6 load control panel.
D. Check that the landing gear are down and locked and ground lock assemblies installed (Ref 32-00-01).
E. Remove dust cap from brake accumulator charging valve (Fig. 401).
F. Discharge nitrogen pressure from accumulator by loosening swivel hexagonal nut on charging valve a maximum of one turn.
WARNING: DO NOT LOOSEN VALVE BODY OR VALVE MAY BLOW OFF RESULTING IN INJURY TO PERSONNEL.
G. Remove connector plug from transmitter.
H. Disconnect pressure gage line to transmitter.
I. Remove transmitter mounting bolts and U-clamp and remove transmitter.
4. Install Hydraulic Brake Pressure Transmitter
A. Install O-ring and union in transmitter pressure port. Apply assembly lube or hydraulic fluid to O-ring and to threads of union.
B. Place U-clamp on transmitter, position over mounting holes in bracket and install mounting bolts (Fig. 401).
C. Connect electrical connector to transmitter.
D. Connect pressure gage line to transmitter.
E. Precharge hydraulic accumulator according to instructions on aluminum foil marker near pressure gage in right wheel well.
F. Tighten swivel hexagonal nut.
G. Install dust cap on charging valve.
H. Check connections for nitrogen leaks.
I. Close BRAKE-PRESS IND circuit breaker on P6 load control panel.
J. Pressurize applicable hydraulic system (Ref 29-11-0 or 29-12-0). Brake pressure gage on the copilot’s flight instrument panel should read approximately 3,000 psi for the applicable system.
K. Check connections for nitrogen leaks.
May 01/00 29-31-21 Page 401 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
Hydraulic Brake Pressure Transmitter Installation 500
29-31-21 Figure 401 May 01/98
Page 402
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
HYDRAULIC FLUID OVERHEAT WARNING SYSTEM - DESCRIPTION AND OPERATION
1. General
A. Two amber overheat lights on the pilots' overhead panel are provided to show when an overheat condition exists in the system B hydraulic pump return line (Fig. 1). When the return fluid temperature exceeds 220\+5°F, the amber light comes on. When the fluid temperature drops to 165°F, the light goes out. The overheat switches are located in the case drain lines near No. 1 and No. 2 system B hydraulic pumps. Twenty-eight volt dc power is supplied to the overheat warning switches through the indicator light circuit breakers on the P6 panel. When an overheat condition occurs, the overheat switch will close, forming a ground and thereby completing the circuit to the amber light on the overhead panel. The amber light will go out when the overheat condition disappears and the overheat switch opens. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737 AMM 飞机维护手册 液压 HYDRAULIC POWER(76)
