Power Steering Pump: Description

Saginaw vane-type power steering pump can be identified by "ham-shaped" fluid reservoir can. Rectangular pumping vanes carried by a shaft driven rotor move fluid from intake to pressure cavities of cam ring.

Centrifugal force throws vanes against inside surface of cam ring to pick up residual oil. As more oil is picked up, it is forced into cavities of thrust plate, into 2 cross-over holes in cam ring and pressure plate and into a high pressure area between pressure plate and housing end plate.

Filling the high pressure area causes oil to flow under vanes in slots of rotor. This forces vanes to follow inside oval surface of cam ring. As vanes rotate to small area of cam ring, oil is forced out from between vanes.