425 bigblock stalls

Sounds more like carb issues than electric. That motor runs very hot and if the float level is low, it would tend to boil the fuel and thats when the motor stops.

I would be looking at the fuel delivery system.

Roy

By the way, do you have the quadrajet or the wcfb?

Roy

I agree with ase. It sounds like a fuel related problem. As he mentioned, these engines commonly ran hot. I would first check for vapor lock with the fuel. If that isn't it, the only other thing I can even think of that could do this is the wiring to the ignition system. Back then, 12 volts were fed to the ignition system on start up only. After that, there was a resister wire that dropped the voltage to 9 volts to protect points, condenser. It helped things last longer. You may want to check the resister wire for thermal issues too.

I love these old cars, but I hate to show my age. (Lol) Acttually, I wasn't born when the car was made. But I worked on a lot of similar vehicles and ones just like your when I was very young.

Let us know what you find. Remember, as ASE said, they ran hot and fuel vapor lock was an issue.

Take care,
Joe

Ok, it could be leaking down from the bottom of the carb. I think we are on the right track for you.

Roy

Not likely. It has a bypass when it gets clogged

Roy

You may need to remove the carb and look underneath it to see if the 2 plugs at the bottom are leaking.

Roy

Not the gasket, you are looking for fuel leakage under the carb.

Roy

I wish I had one for you, but our manuals only go back to about 1975. Chances are you will need to order a manual from a book store or auto parts store.