S 714-042
(11)
Test the steering lockout device.
(a)
Install the nose gear rig and tow safety pin at the nose gear steering system summing mechanism to lock out the hydraulic pressure from the metering valve.
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(b) Using the nose gear upper torsion link, turn the steering
collar to the left (counterclockwise) from the neutral position
15 |5 degrees. Make sure that the collar rotates freely.
NOTE:____ Due to the actuator force unbalance, the steering collar
can continue to move when it is released.
(c) Using the nose gear upper torsion link, turn the steering
collar to the right (clockwise) from the neutral position 15 |5
degrees. Check that the collar rotates freely.
NOTE:____ Due to the actuator force unbalance, the steering collar
may continue to move when released.
(d) Turn the steering collar to the approximately straight ahead
position.
WARNING: IF THE NOSE WHEELS ARE NOT CENTERED IN THE FORWARD
_______ DIRECTION, THE GEAR CAN TURN RAPIDLY TO THE CENTERED POSITION WHEN THE TOW PIN IS REMOVED. THIS CAN CAUSE INJURY TO PERSONNEL IN THE WHEEL SWING PATH.
(e) Remove the nose gear rig and tow safety pin.
S 014-043
(12)
Connect the torsion links at the apex (AMM 32-21-03/201).
S 414-044
(13)
Install the cover support bracket and the cover.
S 864-045
(14)
Close the circuit breakers, for the body gear steering system, as follows:
(a)
P7 Overhead Circuit Breaker Panel 1) 7G23 BODY GR STRG ARM AC 2) 7G24 BODY GR STRG ARM DC
S 864-046
(15) Release pressure from hydraulic system No. 1 (AMM 29-11-00/201).
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S 094-047
WARNING:_______REFER TO AMM 32-00-30/201 FOR LOCK REMOVAL PROCEDURE. RAPID ACTION OF DOORS MAY INJURE PERSONNEL OR DAMAGE EQUIPMENT.
(16) Remove nose gear door lock (AMM 32-00-30/201).
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STEERING METERING VALVE - INSPECTION/CHECK
__________________________________________
1. General
_______
A. This subject has this task:
(1)
Examine the nose gear steering metering valve for leaks.
B.
This task is to make sure that the inlet check valve, compensator, and bypass valve do not leak. Leaks cause a residual pressure decay. If a leak is found the compensator is replaced. If the leak continues the inlet check valve or bypass valve are suspect and the entire metering valve assembly is replaced.
TASK 32-51-04-796-001
2. Steering Metering Valve Leak Check
__________________________________
A. Special Tools and Equipment
(1)
F65-0-3311 - Adapter, (Parker Hannifin)
B.
Standard Tools and Equipment
(1)
Pressure gage - 500 psi
(2)
Hose Assembly - 3/8 inch flareless tube
C.
References
(1)
AMM 09-11-00/201, Towing
(2)
AMM 20-11-28/401, Lockwire
(3)
AMM 29-11-00/201, Main Hydraulic Supply System
(4)
AMM 32-00-30/201, Landing Gear Door Locks
