The hydraulic power steering system consists of the following
components:
For bench repair of the integral power steering gear and the hydraulic
pump, refer to the following information:
• | Power Steering Gear Unit Repair |
• | Power Steering Pump Unit Repair |
The power steering pump is a vane-type pump. The pump houses
the internal components inside the reservoir. The pump operates submerged
in oil.
Two bore openings are located at the rear of the pump housing. The larger
opening contains the following components:
• | The rotor and vane assembly |
The smaller opening contains the following components:
• | The pressure hose union |
The flow control orifice is part of the pressure control union. The
pressure relief valve inside the flow control valve limits the pump pressure.
The power steering gear has a recirculating ball system.
The system acts as a rolling thread between the worm shaft and the rack position.
The lower end of the worm shaft is supported by a preloaded thrust bearing
and two conical thrust races. The upper end of the worm shaft is supported
by an adjusted plug. When you turn the worm shaft right, the rack piston
moves up in the gear. When you turn the worm shaft left, the rack piston
moves down in gear. The rack piston teeth mesh with the sector. The sector
is part of the pitman shaft. The pitman shaft turns the wheels through
the steering linkage.
The control valve in the steering gear directs the power steering fluid
to either side of the rack piston. The rack piston converts the hydraulic
pressure into a mechanical force. You can control the vehicle manually if
the steering system becomes damaged and loses hydraulic pressure.