Re: Fuel Boiling Out Of Carburetor

Posted by Tim Cole On 2015/9/7 8:03:35

One opinion I've seen is that the more volatile elements are boiling off leaving a fuel that is not good for starting. This causes the motor to flood while better fuel is being cycled through the carburetor. Thus, the extended cranking - not at all good for an old starter.

So I think another test might be to keep some fuel in the trunk and try dumping a half-shot or more in the intake prior to a hot start.

This opinion seems supported by the fact that updraft carburetor cars don't have problems as severe as downdraft cars.

However, this doesn't explain why, if the car sits overnight it will start, while not when it is hot.

The last carburetor car I owned started immediately when hot, but seemed to take longer after I owned it for seven years. But I was living in Texas and Oklahoma at the time and it was super hot in summer. I had an older high mileage Dodge that cranked forever when it was hot. At the time I had a 2 mile commute so I didn't care.

It would be nice if I had one of these problems to look at, but presently I'm involved in fuel injection.

The trailered cars don't run very much so the owners never cared, although one of the last Packards I worked on had a hot starting problem that was almost completely eliminated after installing new cables from Rhode Island Wiring.

I also handled a 359 that, no matter what I did, always had at least .75 voltage loss through the block to the starter. The only solution was a non-standard ground cable bolted to the starter.