DESCRIPTION & OPERATION
Power steering is provided by an open center, rotary type control valve which directs oil from power steering pump to either side of integral rack piston. Road feel is controlled by diameter of torsion bar which initially steers vehicle. As required steering effort increases, torsion bar twists, causing a relative rotary motion between rotary valve body and valve spool. This movement directs oil behind integral rack piston, which in turn, builds up hydraulic pressure and assists in turning effort.
Hydraulic pressure for operation of power steering gear is provided by a belt driven Saginaw T/C power steering pump. The power steering pump is a constant flow rate and displacement vane type pump. Drive tangs on power steering pump mate loosely with a stub shaft. This permits manual steering control to be maintained if drive belt on power steering pump should break.
Initial Power Steering Pump Operation
- Fill pump fluid reservoir and let fluid level settle for at least 2 minutes. Start and run engine for a few SECONDS, then turn engine off.
- Add power steering fluid to reservoir (if necessary). Repeat engine start/stop procedure until fluid level remains constant after running engine. Raise vehicle off ground.
- Start engine. Slowly turn steering wheel from left to right, lightly contacting wheel stops. Add power steering fluid to reservoir (if necessary). Lower vehicle to ground.
- Slowly turn steering wheel from lock to lock. Stop engine. check fluid level and fill as required. If fluid is extremely foamy, allow vehicle to stand a few minutes and repeat procedure.