Power Steering Pump ID

[dkamp]

While doing some power steering pump work I considered a pump replacement. I noticed that for a Saginaw pump that there were several pumps to choose from. What features should be considered? Example, if I needed a pump and was looking at a friends junk pile, how would I know one from the other? On Rockauto several seemed to have the same bolt holes for mounting.
even between different years Saginaw seems to "look" the same except for what pully is used.

 

[oldkimmer]

There is different shaft lengths that space the pulley at different depths. I think 68/69. Then 70 up has 2 different bracket styles. Kim

 

[Bewy]

Early pumps had a key way in the shaft & pulley was retained with a nut. Later models had a pressed-on gear.
Internally, two differences:
- the outlet fitting where the high pressure hose connects. The hole through that fitting can vary in size & controls the flow volume.
- behind the fitting is the pressure valve. Pressure is increased by removing shims; some may have no shims.
- behind the PV there should be a spring.