Steering System: Description
Integral power steering unit consists of a rotary hydraulic control valve housing, input shaft/worm gear/valve sleeve assembly, sector shaft, and 1-piece piston containing 27-29 recirculating balls. The 1-piece piston's teeth are meshed to sector shaft teeth. Sector shaft is connected to Pitman arm.
Rotary hydraulic control valve assembly contains upper input shaft/valve sleeve, sleeve Teflon seals, and internal torsion bar. The input shaft/control valve sleeve is retained inside control valve housing by bearing and lock nut. Hydraulic action is generated by relative rotary motion between input shaft/control valve sleeve and worm/piston assembly. See Fig 1 and Figure.
Vehicles use Saginaw power steering pump. Pump is a constant displacement vane type. See Figure. The reservoir is "O" ring sealed onto the pump housing. All integral pump moving parts are submerged in fluid. The fluid filler opening is on top of reservoir, unless engine type requires alternate remote reservoir. Pump reservoir cap is sealed when using remote reservoir.
Rectangular pump vanes, driven by main pump shaft, are mounted into rotor and cam. Vanes move fluid from reservoir into cam ring. Fluid is pressurized by vanes in cam ring and then forced into cavities of thrust plate, through flow control valve. The flow control valve regulates pressurized fluid to the steering gear unit.