S 424-013
(5)
Install the compensator in the boss. Use the crowfoot wrench to tighten the compensator to 275-300 pound-inches.
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(6) S 434-014Install lockwire on the compensator.
(7) S 864-015Supply electrical power (AMM 24-22-00/201).
S 864-016
WARNING: MAKE SURE ALL PERSONS AND EQUIPMENT ARE AWAY FROM THE NOSE
_______ WHEEL STEERING SYSTEM BEFORE YOU SUPPLY HYDRAULIC POWER TO THE SYSTEM. PARTS OF THE NOSE WHEEL SYSTEM CAN TURN AND CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
(8) Pressurize the left hydraulic system (AMM 29-11-00/201).
S 034-017
CAUTION: MAKE SURE THE TOP TORSION LINK IS HELD IN THE HORIZONTAL
_______ POSITION (AT A RIGHT ANGLE TO THE OUTER CYLINDER OF THE SHOCK STRUT) WHEN YOU DISCONNECT IT. IT CAN CAUSE DAMAGE TO THE SENSOR TARGETS DURING THE STEERING TESTS.
MAKE SURE THE SENSOR TARGETS DO NOT TOUCH THE ADJACENT STRUCTURE WHEN YOU MOVE THE STEERING SYSTEM FULLY LEFT OR RIGHT. IF THE SENSOR TARGETS TOUCH THE ADJACENT STRUCTURE, THE SENSOR TARGETS CAN BE DAMAGED.
(9)
Disconnect the torsion links for the nose landing gear at the apex joint (AMM 32-21-09/401).
S 394-018
(10)
Turn the steering tiller to operate the nose wheel steering through the maximum left and right steering. Do this a minimum of six times to bleed air from the system.
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S 714-019
(11)
Do the steps that follow to make sure the tiller handle steering operates correctly:
(a)
Turn the tiller handle from the center position in the clockwise direction until the adjustable stop bolt on the trunnion drum touches the stop that does not move. Hold the tiller in this position.
(b)
Make sure that the angular movement of the steering collar is 65 |1 degrees.
(c)
Release the tiller. 1) Make sure the tiller goes back to the center position without help, in 4 seconds.
2) Make sure that the steering collar goes to |1 1/2 degrees of the center position.
(d)
Do the five steps before this again, but turn the tiller handle counterclockwise.
(e)
Make sure there are no hydraulic leaks at the metering valve compensator.
F.
Put the Airplane Back to Its Initial Condition
S 864-020
(1)
Remove the pressure from the left hydraulic system
(AMM 29-11-00/201) if it is not necessary.
S 614-021
(2)
Make sure the fluid in the left hydraulic reservoir is at the correct level. Fill if it is necessary (AMM 12-12-01/301).
(3)
Remove electrical power (AMM 24-22-00/201) if it is not necessary.
S 434-023
(4)
Connect the torsion links for the nose landing gear
(AMM 32-21-09/401).
S 864-024
(5)
Make sure the not compressed sensors and targets for the nose landing gear are not damaged.
S 864-022
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LANDING GEAR POSITION INDICATING AND WARNING SYSTEM - DESCRIPTION AND OPERATION
_______________________________________________________________________________
1. General
_______
A. The system shows status of landing gear and gear doors to the pilots. Two independent landing gear subsystems are used to provide redundant control to indication lights and EICAS (Engine Indication and Crew Alerting System) messages.
B. The system also provides inputs to the aural warning system, landing configuration warning module (Ref 31-51-00).
C. The system consists of indication lights on the pilots center instrument panel P3 and EICAS messages on the upper EICAS display. The system receives gear position signals from the PSEU (Proximity Switch Electronic Unit) to turn on or off the indicator lights and EICAS messages. Proximity sensors which provide landing gear and door position signals to the PSEU are part of the proximity switch system (Ref 32-09-03).
2. Component Details
_________________
A. Indicator Lights (Fig. 1)
________________
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