It's hard to be sure whats going on sometimes when just reading response's.
There's always the chance it could be getting flooded by you pumping on the gas trying to start it and possibly in combination the ignition might not be working. If it has an MSD it won't fire with a low battery but will crank over fine. You can always fill the carb put fresh plugs in it and pinch the fuel line shut and see if it will start. If it doesn't it ain't the pump.
