Jerry,

If I'm properly comprehending what is happening, try pumping your
primer bulb when the engine is NOT running and see if this happens. If
it does, then it's probably a stuck float. If so, you'll need to remove
the bowl to investigate further. I don't know the age of the engine,
but if it's fairly new or it hasn't been too long since it's been
rebuilt, then you *might* be able to get away with not having to replace
the gaskets (recommended that you replace them!).

Hope this helps,
-Jim