Do a pressure and volume check on your fuel pump. Disconnect the fuel line at the carburetor, deadhead it into a 0-10 Lb. pressure gauge and start the engine. The fuel pressure should be 3-5 PSI, and should stay up for several seconds after shutting the engine off. Then connect a vacuum gauge to the inlet side of the pump after disconnecting the fuel line from the frame. Run the engine. The vacuum should be 10 inches of mercury or more, and should remain for about the same time as the pressure after shutdown. Reconnect the inlet line and route the outlet into an empty oil bottle or other 1-qt. container. Idle the engine for 30 seconds on the fuel in the float bowl. The pump should produce at least a pint of fuel in 30 seconds at idle. Be sure to vacuum check the flex line between the pump and the frame- - -sometimes a flex line with a pinhole can suck air without leaking fuel.
Failing either the pressure or vacuum test means you have a bad fuel pump. If it passes the pressure/vacuum test and won't pump a pint of fuel at idle, you have a restriction in the fuel line from the tank to the pump or a restricted pickup tube in the tank. Unless there are very unusual circumstances happening, "Vapor lock" is about as much of a myth as Santa Claus or the Easter Bunny!
Jerry
