Re: Vapor lock

Posted by Craig Hendrickson On 2009/6/26 11:14:22

I believe that vapor lock was a pretty common problem. It is only made worse today by the current gasoline formulas as pointed about by West Peterson above.

Just an electric pusher pump solved this problem 100% on my 55 Pat and I have driven it in 110F during the Summer.

A fuel return system is a good idea, but the problem comes in the complexity of the plumbing. No Packards have a return fuel line, so that would have to be laid front to back and somehow connected to the fuel tank, not a convenient thing. If I were going to plumb this I would probably use a fuel bypass regulator at the inlet of the carb. Typical electric fuel pumps will output 6-7psi and the older carbs can get by with 4psi, so one might need a regulator anyway, although my 55 Pat with 4GC did not.

Craig