A-A
METERING
VALVE
MODULE
BRACKET
LEFT SUMMING
STEERING INPUT
CONTROL LEVER
CONTROL ROD
BOLT METERING JAMNUT VALVE
N55 RIGINPUT ARM PIN HOLE
A B
Nose Wheel Steering Metering Valve Module Installation Figure 401
K26388
 

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A

757
MAINTENANCE MANUAL

 S 864-003
 (2)  
Make sure the pressure is removed from the left hydraulic system and reservoir (AMM 29-11-00/201).

 S 864-004

 (3)
Move the towing lever on the metering valve to the TOWING POSITION.

 S 494-005

 (4)  
Install the towing lever lockpin.

 E.
Remove the Metering Valve

 S 024-055
 CAUTION: DO NOT LET THE TORSION LINKS FALL FREELY WHEN YOU DISCONNECT
_______
 THE TORSION LINKS. DAMAGE TO THE TORSION LINKS OR THE
 PROXIMITY SENSORS AND TARGETS CAN OCCUR.

 (1)
Disconnect the torsion links at the apex joint (AMM 32-21-09/401).

 S 984-009

 (2)  
Turn the top torsion link to align the steering collar and the support plate with the zero position on the indicator scale. Make sure they are less than 1/4 degree from the zero position.

 S 014-010

 (3)  
Remove the cover for the summing mechanism.

 S 034-011

 (4)  
Remove the brackets.

 S 494-012

 (5)  
Install the rig pins NS1 and NS2 in the captain's forward quadrant and the interconnect mechanism (AMM 32-51-00/501).

 S 034-013

 (6)  
Loosen and disconnect the steering cables NWSA and NWSB at the turnbuckles (AMM 32-51-00/501).

 NOTE: The turnbuckles are behind the access hole cover in the
____
 wheel well for the nose landing gear.

 S 034-014
 (7)  
Disconnect the input control rod from the metering valve (Detail A).

 (8)  
Disconnect the hydraulic lines from the metering valve.

 S 034-015
 

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757 MAINTENANCE MANUAL
 S 494-016
 (9)
Install caps in the lines and plugs in the ports.

 S 034-017

 (10)
 Remove the three bolts that hold the metering valve to the bracket for the control valve.

 S 024-018
 CAUTION: MAKE SURE THE SWIVEL VALVES AT EACH END OF THE METERING VALVE
_______ MOVE EQUALLY DURING REMOVAL. YOU CAN CAUSE DAMAGE TO THE VALVE TUBE IF THE SWIVEL VALVES ARE NOT REMOVED EQUALLY.
 (11) Remove the sealant and use the spanner wrench to loosen the retainer nuts for the swivel valve. Loosen them equally at each end of the metering valve. Be careful when you remove the metering valve to prevent contamination of the open hydraulic ports (View A-A).
 NOTE: The hydraulic ports will be open when you remove the metering
____ valve from the actuator trunnions. Make sure the area around and in the trunnions is clean before the hydraulic ports are open to prevent contamination.
 S 494-019
 (12)
 Install caps in the open hydraulic ports for the swivel valve and actuator in the actuator trunnions.

 S 034-020

 (13)
 Remove the hydraulic fittings from the metering valve.

 S 494-021

 (14)
 Install plugs in the ports.

 TASK 32-51-12-404-022
 3. Install the Metering Valve for the Nose Wheel Steering (Fig. 401)
______________________________________________________
 A. Equipment
 (1)
Rig Pins from Set B20003-XX (AMM 20-10-24/201).

 (a)
NS1 - P/N B20003-20

 (b)
NS2 - P/N B20003-24

 (c)
NS3 - P/N B20003-5

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757 MAINTENANCE MANUAL
 (d)  
NS5 - P/N B20003-5

 (2)  
Spanner Wrench - F72959-35

 (3)  
Trunnion Nut Wrench - A32035-1

 (4)  
Towing Lever Lockpin - A09003-1

 B.
Consumable Materials

 (1)  
D00153 Fluid-Hydraulic - BMS 3-11

 (2)  
D00015 Grease, Corrosion Preventive - BMS 3-24

 (3)  
A00247 Sealant-Chromate Type - BMS 5-95
　
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