Flooding is when excess fuel is getting into the engine. It can be gas running over the top, or through the vent hole, out the throttle shaft, or just running over rich.
Fuel inlet needle damaged. The needle can easily be damaged when adjusting the float. Do not put any pressure on the needle. Dirt in the seat, or coated with stale gas can also cause the needle to leak.
Float weight - Weigh the float. It should be close to 15 grams. If not, then replace the float.
Move the float up and down by hand to make sure it isn't rubbing. Each pontoon should be centered in the bowl.
Float level - Set to 13/16" to 1" with the top inverted.
Fuel Pump - Pressure may be too high. Should be 4 - 4.5 lbs. New pumps are especially suspect. The Chinese pumps are not very accurate.
Secondary Fuel Inlet - Most 4300 carburetor have had the secondary fuel valve blocked off. If not, replace with this one.