You really would have to have a fuel pressure gauge spliced in to measure the pump pressure to diagnose it. Or disconnect the fuel line and crank the engine (with primary coil disabled) with the fuel line inside a glass jar, and observe whether it delivers constant fuel supply.
Very possible that it's flooding, and that pumping the gas gave it more air to compensate by opening the throttle plate. And that's why it would take 45 minutes for it all to evaporate before it would start.
Flooding vs fuel starvation should be easy to tell, by removing the air cleaner lid and smelling for gas. If none, starvation. If heavy odor, flooding.
Very possible that it's flooding, and that pumping the gas gave it more air to compensate by opening the throttle plate. And that's why it would take 45 minutes for it all to evaporate before it would start.
Flooding vs fuel starvation should be easy to tell, by removing the air cleaner lid and smelling for gas. If none, starvation. If heavy odor, flooding.