When i have the float bowl off.....I attach the fuel hose to the fuel inlet of the carburater, then as I let the float drop I should be able to blow thru the hose, when I push the float upward towards the carb, the needle will stop against the seat and you will not be able to blow air thru, I repeat this a few times to make sure the needle is not hanging up or sticking. But this will let you know if the float operates freely and if the needle and seat works properly. One thing you might also want to check is, has the float sunk, in other words will it fill up with fuel when immersed?this would make the engine flood also.
Good to know if I am ever in anchorage and need my hose blown on.