1969 L36 AIR Smog Equipment

[David B.]

I need a little help please - there seems to be nothing in the archives on this question.

I would like to find out what the correct part number is for the smog pump assembly for a 427/390 1969 (a late 68 build date if that matters)? I have researched Prince's Corvette Restoration Guide and also Bizzoco's Guidebook and also the '69 AIM. I am coming up with different information between sources. Please advise on:
smog pump part # (7801149?, 7803948?, other?)
diverter valve #
As best I can determine, the correct pump should not have a relief valve (apparently, they only appeared on the higher HP rated BB's)
I know what the correct pulley number (3925522) is so I don't need that. But, any other key numbers that might be helpful on this assembly are also appreciated.

Thank you in advance to any AIR gurus.
Dave B.

[Dick W.]

Re: 1969 L36 AIR Smog Equipment

Early '69's could have the relief valve in the case. The casting # is 7805650 for the later pump and 7801135 for the early style. All this can be found the the 1968-1968 [Technical Information Manual and Judgeing Guide] that is available for purchase on the web site.

[Greg L.]

Re: 1969 L36 AIR Smog Equipment

David

If you are looking for an assembly number for the pump you might be out of luck because I'm pretty sure that all you will find is a date stamp and as Dick mention, casting numbers. I don't think that the pumps had the actual assy number on them.

[Joe L.]

Re: 1969 L36 AIR Smog Equipment

David and Greg----

Yes, that's how it is. The part number for the complete pump assembly is nowhere to be found on a pump assembly. What you will find is a casting number for the rear plate (easy to see) and a casting number for the aluminum pump housing (very hard to see). The rear plate casting number does not necessarily identify the correct 1969 pump since it was used for many other pumps, too.

Your car would have used a pump with no external relief valve on the pump casting. This same style pump was used for 1969-75 applications. This style pump is not very hard to find.

The diverter valve used for 1969 big blocks had a "T" fitting at the top. I don't recall the number and I'm out-of-town right now so I can't look it up. However, I can tell you that this is a VERY hard-to-find and EXPENSIVE valve.

[Greg L.]

Re: 1969 L36 AIR Smog Equipment

I don't know the full P/N but the one I got for mine has the number 29298 stamped in it which is correct for a 69 L-36.

I bought it two years ago and it wasn't too hard to find thanks to Bill Hodel but it wasn't cheap either compared to the rest of the smog equipment!

[David B.]

Re: 1969 L36 AIR Smog Equipment

Dick, Greg, Joe,

Thanks for the helpful information. Now I know what to look for. Also, I have been looking at the repro manifold tube lines that Crane's is offering. They seem pretty good, but opinions and suggestions are appreciated.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&viewitem=&item=4601383531

David B.

[Dick W.]

Re: 1969 L36 AIR Smog Equipment

Suggest that you check the archives for Crane's