Hello, New to this board, found it on the internet while trying to find tips on Vapor Lock. I did some searches on past post here, and have sent those to my father, but thought I would post up to see if there were any other pointers Let me say that I am Sorry for the long first post. What I have: 1931 Model A Deluxe Coupe W/48 Flathead. Little background of the car This was my father car , and is now mine, and we have been working on getting running. Its been sitting for almost 30 years. It has all new brakes and hydralics all the way around (Juice brakes). New radiator, gas tank cleaned out with acid, carb rebuilt. We pulled the engine to fix the tranny (First gear was out.). Along with some other things. Car is all back together but we seem to be getting vapor lock after running the car (Just in the garage not driving at all). After it seems to be getting hot The carb was rebuilt, I am not 100% sure on the fuel pump if its new or not. Fuel filter is good (to my knowledge anyway). New Coil, plugs etc. Getting sparks. It seems to start and run after it cools down. Strange question though. The coil DID have the Ballast Resistor installed on the coil. But while it was connected, if we started the car the started seem to want to continue running. When we bypassed the coil, then it would start fine. Does this Ballast Resistor need to be installed. Maybe we have it hooked up wrong. Thanks in advance for any help.
You should have a ballast resistor to the coil. The coil should get full voltage during crank and then the reduced voltage through the ballast resistor when the engine is running. You may be getting a high voltage which is overheating the coil and causing what you think is vapor lock.
Check the fuel line to ensure it is not damaged, crushed or pinched. This would present a vapor lock situation. I came across this with my Caddy.G.