Ignore the answer from Darrell as black smoke indicates a fuel problem whereas white smoke indicates an oil problem.
Stick with my prognosis and you won't go too far wrong
pleasant
September 2008
you either have too much oil in it, the wrong kind of oil, such as 2 stroke oil(not mixed in the gas, just insted of sae 30 motor oil) i had a cousin that did this, lol, or you need a new set of rings (rebuild motor)
darrell
September 2008
Assuming it's a Briggs engine of the type that has the carb on top of the tank, then it would be the carb diaphragm that needs replacing.
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