There is this one on E Bay.
http://cgi.ebay.com/ebaymotors/REBUILT- ... dZViewItem
But When I had mine rebuilt it was doing the same thing. I took it back and the guy found a small o ring that had fallen out of place. I'm not sure where the o ring is from or where it belongs in the carb, but that is what he told me. It happened to me on my 78 carb also at a different carb shop, but I just ended up buying a new rebuilt carb for the truck. But I bet it was the same o ring. It sounds like it might be a tricky o ring and it happens to many of them.
If you do have your carb looked at, you might mention this so maybe he will find it and fix it.
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OK, I'm over it. Where's the beer?
