Power Steering Pump Pulley Size?

[colnago]

I have two power-steering pumps. One came off of a '71, but I have no idea about the other. Both have pullies installed. On one, the pulley diameter is about 5", and on the other, it's about 4-1/2". Assuming the pumps are both good, is there a "better" or "correct" pulley diameter? Or, is the difference so small, it becomes a "don't care"?

Joseph

[Mach428]

I believe the different pulleys will have different set-back. You should try to bolt them up and see if one will match your belt alignment

[Belll03]

It depends on the pulley on the other side

[Mach428]

I've never seen a crank or WP pulley with different set-back as both are fixed. The alt and PS pulleys vary as does the brackets that mount them

[colnago]

Mach428, you are correct. The offsets are very different. I'll probably use whichever one lines up with the unused groove on my crankshaft grooves.

I also noticed that one pump had "feet" cast into its body where it mounts to the bracket. Also, one of them has one flat spot along the back edge, and the other has two. Final note of possible interest. One of the dipsticks said to use ATF fluid.

Joseph