If you want a good book on Quadrajet rebuilding and tuning Carbking posted this book sometime ago "How to rebuild and modify Rochester Quadrajet carburetors" by Cliff Ruggles. I have a copy excellent book. In addition to what 55 tractor said there are also couple of seals in the bottom of the float bowl that need to be checked for leakage. The book also explains that Qjets were tuned for a particular engine and switching to another engines requires retuning the Qjet, it's explained in the book.

Larry

I don't own a vehicle that isn't old enough to drink.