GILLIG LOW FLOOR, Руководство по обслуживанию

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Hydraulic System
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STEERING SySTEM
The steering system consists of the steering wheel, steering column and shaft assembly, power steer-
ing gear, pitman arm, drag link, and tie rod. A gear type hydraulic pump, reservoir, and interconnecting
system lines and hoses are also used in the system.
The steering gear assembly is mounted on a bracket attached between the forward two outriggers on the
left side of the chassis, directly beneath the driver’s platform. The steering column extends through the
floor and, using a universal joint, attaches directly to the input shaft of the steering gear. The upper end
of the steering shaft has the steering wheel attached, using a hardened washer and lock nut. The horn
contact, spring, and button are mounted in the hub of the steering wheel.
The frame mounted steering gear is a recirculating ball type and contains an integral power cylinder and
control valves. A hydraulic supply line connects the steering gear to the hydraulic pump and a return line
routes fluid from the steering gear back to the reservoir.
The steering gear hydraulic system is equipped with two poppet valves, one at each end of the rack pis
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ton, to allow pressure relief when the steered wheel approaches the axle stops. The tripped valve reduces
pressure in the gear box and thus helps to reduce heat generated by the pump and prolongs the service
life of the gear and pump.
Routine Maintenance
The power steering system requires little maintenance; however, the system should be kept clean to
ensure maximum operating performance and trouble free service. Periodic inspections should be made
to check for leaks.
At regular intervals, check the fluid level in the reservoir and add fluid as needed. Refer to the “Hydrau -
lic System Reservoir” section earlier in this chapter for the method of checking and filling the reservoir.
The Lubrication and Maintenance section will list the type of fluid to be used and the recommended fluid
replacement interval.
The fluid reservoir assembly is located in the right corner of the engine compartment. When the slight -
est evidence of dirt, sludge, or water is discovered in the system, disconnect the fluid lines at the steering
gear and drain the system. Refill the system with the recommended fluid.
Air in the fluid system will cause “spongy” action and noisy operation. When any hose has been discon
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nected or when fluid has been lost for any reason, the system must be bled. Bleed the system as de -
scribed in “Bleeding the Power Steering Hydraulic System.”