[P.S.]

Originally Posted by Kohnke Rebabbitting

If your motor pops and bangs, it is electrical.

If the motor pulls down, and sputters, it's running out of gas.

I know you said you cleaned the tank out, we did the same thing with a 1949 Ford truck once. Cleaned the tank two times, and found nothing, but the third time we found a small piece of cork off an old sending gauge that would suck over the outlet hole and shut down the gas, and then stop the motor. We would leave it set for 10 minutes, and it might run good again for another 10 minutes, or a whole day.

He's using the screen filter on the top of the shutoff valve like Tom preaches. It eliminates that possibility.