On a serious note, and assuming this is a pedestrian mower and not a ride on or a tractor mower, then there are two probable causes. Firstly overfilling the engine with oil. Remove dipstick, clean and replace- then remove and check level. It should be no higher than the max fill mark. If is is, then drain off the excess, re-check the level and start engine and run for 5 minutes or so. If it was over filled then the smoke should clear.
Secondly (and most likely) at some stage you have tipped the mower on its side for inspection or cleaning purposes. This will allow the oil to migrate from the sump into the exhaust, so when placed back on its wheels and started it will smoke- sometimes a little, sometimes a lot depending how long its been laying on its side. If this is the case, run the engine for five minutes or so, and it should burn off the excess oil and clear.
pleasant, August 2008
