im still having problems with my 48 cub overfueling, it blows black smoke, and fouls the plugs frequently, now, what ive tried, the carb has been overhauled with 2 different kits, and it and its passages are clean as it can be, the adjustment is as lean as possible without stumbling, starting with 1 full turn from seated, is it possible somebody has changed the jet size in the past? where can i find the factory jet? i bought a new carb, its the zenith, and is a physically larger carb, at least the size of the air intake is, this one has to idle fast,the cubs linkage wont let it idle down without killing the engine, which is not really a problem,. but it too feeds more gas then the cub needs, not as bad as the factory carb but id still like to get it better, again its leaned out until it just runs smooth, the old cub is now semi retired and only pulls my feed trailer twice a day, which varies in weight between 500 and 2000 lbs depending on how full the water tank on it is , its on reasonably level ground, so the old cub handles it fine, i hate to have a old tractor just sit and do nothing, it bugs me, as well as keeps my other tractors available for use, including another cub, any help would be appreciated