Power steering pump identification

[Tom L.]

My 1970 454 was purchsed as a project car and the power steering pump was missing. I purchased one from a vendor and I am nearly certain that it is the wrong one. In fact, the pully they sent with it doesn't even fit on the shaft. The pully is part number 3878245, has a shaft hole with a diameter of .620 and is for two belts. The shaft diameter on the pump is .750. Could someone please tell me if either are correct? Thank you.

[Tom L.]

Re: Power steering pump identification

Sorry, I spelled pulley wrong. I should proof read these things before I post them.

[Joe L.]

Re: Power steering pump identification

Tom-----

You are absolutely correct. You have the correct pulley but the wrong pump. The pump that you have is the 75-79 style pump. Some references list it as applicable to 74, too, but those are incorrect.

The pulley you have, which was used for all 1965-74 Corvette big blocks with power steering is designed to fit on the tapered shaft pump which also uses a special lock nut for pulley retention. The pump that you have has the 75-82 style shaft which uses a pulley with an interference fit only. There is NO pulley ever made by GM with 2 grooves (necessary for most Corvette big block applications) which will work with the 75-82 style shaft. So, you need to get the right pump.

Incidentally, the other aspect of incorrect configuration for the pump you have is the reservoir. This style reservoir was not used for 1974 except, POSSIBLY, for very late cars. Functionally, it will work for a 1974 (or, even, earlier) but it won't work if it's attached to a pump with the wrong shaft.

[Tom L.]

Thanks again Joe. One more question.

Joe,

Do you know where I could find a picture of a correct 1970 BB reservoir? I understand from the judging guide that the BB filler neck is slightly different than the SB for 1970.

P.S.- I truly appreciate your willingness to share your wealth of information on these cars. You have stepped up and answered my last dozen questions on this forum. This project would be significantly more difficult without your input. Thank you.

[Joe L.]

Re: Thanks again Joe. One more question.

Tom-----

Actually, I don't think there is any difference with respect to the power steering reservoir used for a 1970 small block versus big block. The pump used for both applications was a GM #7808286 and the 7808286 pump used the GM #5696997 reservoir. This same reservoir was used for 1967 through 1974.

[Joe L.]

Addendum with Photo

Attached is an AC-Delco photo of the configuration pump you require. This re-manufactured pump can be purchased from AC Delco delaers under Delco #36-516086 for about 90 bucks. It may also be available though GM dealers under GM #88985122.

[Joe L.]

Oops! Here's the Photo

Photo Attached