I do a 3-part test on fuel pumps. Idle the engine for 30 seconds with the fuel line at the carburetor routed to a catch container. If the engine won't idle that long on the fuel in the float bowl, you've got other problems to fix. You should get at least a pint of gas in the catch can. Then deadhead the fuel line into the pressure gauge and idle the engine for a few seconds. You should see 2-4 PSI on the pressure side of the gauge and the pressure should remain for several seconds after shutdown. This tests the pump output check valve. Connect the gauge to the inlet side of the pump and idle for a short time. You should see 10" of vacuum or more and it should stay there for a while after shutdown. That's the inlet check valve test. If the pump passes all these tests and it isn't leaking gas anywhere it's good. Start looking for a restriction upstream of the pump somewhere. I once had a flathead Ford engine that would run about a mile, quit, and wouldn't restart for several minutes. After a huge amount of diagnosis, I found a big grasshopper lodged in the pickup tube in the gas tank!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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