1 Answer

Reasons for oil in spark plug chamber:

Over Filled Oil
If a lawn mower engine is filled with more oil than the manual indicates is necessary, the crank case can overflow and cause oil to leak onto the spark plug. The solution is somewhat self explanatory. Remove the oil cap and turn the lawn mower over to pour out some of the oil. Recheck the level to make sure you have not removed too much, and add oil back as necessary. IS WORTH REPAIRING

Piston Seals
One potential source of oil on your spark plug is a blown piston seal. The seals keep oil from leaking into the combustion chamber and, if blown, can manifest themselves by spraying oil on the spark plug. This is not a user-serviceable part, as it requires an engine rebuild. Contact your local authorized dealership for your particular make and model lawn mower. NOT WORTH REPAIRING UNLESS YOU SPENT THOUSANDS FOR THE MOWER.

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