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Power Steering Pump: Description

Two different types of Saginaw vane-type power steering pumps are used. The Model P pump is mounted inside the reservoir. The Model TC pump is mounted below the reservoir. On both models, the vanes are driven by a rotor and moves fluid from the intake to the pressure cavities of pump ring.

Centrifugal force moves vanes against inside surface of pump 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 pump 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 the vanes in slots of the rotor. This forces vanes to follow inside oval surface of pump ring. As vanes rotate to small area of pump ring, oil is forced out from between vanes.