5 Answers

Your oil is leaking somewhere and the block is over heating. Have it serviced. 

Check the choke, it is also running rough?? 

Assuming you are talking 4 cycle, did you somehow get oil in the gas>??

oil burning in cylinder carbonize at top of cylinder inition by hot carbon

Mine was the same. I changed the air filter and now it is OK.

Use the lawnmower's oil dipstick to determine whether the oil level is correct. Maintain the correct level of oil. If you've overfilled the oil, open the drain plug, and drain some of the oil into a waste container. Dispose of any excess oil properly. Burning off excess oil is undesirable. It can foul the mower's spark plug, piston rings, and other engine components and contributes to air pollution. If your mower's engine has not been overfilled with oil, but still is smoking, it may have stuck or worn piston rings or another maintenance problem.

Some maintenance shops offer a mower transport service. Check to see if this is available in your area.

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