unhook the power from the electric fuel pump and start the engine and see if it smooths out before it runs out of gas .. that will give you a pretty good indication of a flooding problem ...and then when you hook the fuel pump back up see if it bogs down as it primes/fills the carb ... and look down the throat of the carb and see if fuel is running thru the carb when it shouldn't be ... but don't look down the throat with the motor running ...