you need to remove the carby from manifold then remove the bottom bowl from this carby, you will notice a float this must be able to move slightly up on the float bracket, check all very closely plus check to make sure there is no fuel inside the float, if you see fuel inside this float , its no good, you must replace it. if all looks ok you must remove the float assembly and check the small needle in seat which is connected to the opposite end of this float bracket. where the small needle is positioned in the seat if there is a tiny piece of crap this will cause the needle not to shut off correctly and cause flooding of the carby. make sure all is spotlessly clean before re- assembly.