AIR smog pump

[Leonard M.]

I purchased this AIR pump for the original white fan to use on my 1970. The stamped date code is 29071Z, based on the white fan, case design and 7801149 cast back I figure it's dated the 290th day of 1967. I cleaned it up somewhat, it was crusty untampered with when I got it. Question is; what application is it for since it doesn't have a pressure relief? Also the Z in the stamp?

[Edward B.]

Re: AIR smog pump

Leonard, typically, lower horsepower pumps in 1968 didn't have the relief valve so it probably came from an L6 or lower HP V8. The Z in the stamp is the configuration code of the pump. 1968 pumps with a pressure relief valve installed in the pump were coded Y. Non-pressure relief valve 1968 pumps were coded Z.

Ed

[Joe L.]

Re: AIR smog pump

I purchased this AIR pump for the original white fan to use on my 1970. The stamped date code is 29071Z, based on the white fan, case design and 7801149 cast back I figure it's dated the 290th day of 1967. I cleaned it up somewhat, it was crusty untampered with when I got it. Question is; what application is it for since it doesn't have a pressure relief? Also the Z in the stamp?

Leonard------


These pumps were used across all GM car and truck lines. They were by no means unique to Corvettes or, even, Chevrolets. Pumps without a relief valve were not used on 1968 Corvettes, though. So, this one was originally installed on some other application. As well as some 1968 applications, this configuration pump was used from 1969 to 1975 for most GM applications. All 1969-75 Corvettes, except 1969 L-88 and ZL-1, used this configuration pump.

[Leonard M.]

Re: AIR smog pump

Thank you Ed

[Leonard M.]

Re: AIR smog pump

Thank you Joe. I read much of what you wrote in the past about AIR pumps applications in Corvettes and figured that you would have a answer to this one. As you say, based on the date stamp, this pump, along with a diverter valve with pressure relief, was used for "some" 1968 GM vehicles other than a Corvette. And, pumps with this case and the 7801149 back was typical for most 1969-1975 Corvettes.

[Harry E.]

Re: AIR smog pump

Glad you asked your questions here Leo as I am starting to look hard at my 1970 smog part numbers and pondered similar questions

Harry