1987 Fleetwood 26C motorhome is on a For...

My 1987 Fleetwood 26C motorhome is on a Ford E350 chassis with a 460cuin gasoline engine with a carburetor and automatic transmission.

I have been having problems getting it started but once it starts it runs fine and then starts up fine as long as I am using it. When I let it set for a while it is the same scenario all over again. There is plenty of gas in the fuel tank and no visible leaks. The fuel tank is in the rear of the extended chassis.

Yesterday I tried to start it but it wouldn’t start. After pumping the gas peddle for a while the engine caught but would die down like it was starving for gasoline.

What’s the problem? I am thinking it is either the fuel pump or carburetor. I can remove the fuel line and check the fuel pump by visually seeing if adequate fuel is being pumped to the carburetor. If that is not it I assume I need to remove the carburetor and either replace it or rebuild it. What do you suggest?
albarrs@wfeca.net