More likely it's either overfilled with oil, or it's been tipped on it's side and the muffler is full of oil. If the latter, just let it burn off, and top up the oil if needed.
phil_saunders(a)bigfoot.com
Phil Saunders
June 2009
could be head gasket and a valve/piston
bigal
June 2009
I can answer this question...
mountfield rv150 petrol lawn mower hand propelled?
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Try fixfault.com to fix lawn mowers.