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So I purchased a second hand lawn mower with a B&S 10T802 engine. The previous owner already informed me that the lawn mower had been severely overfilled with oil once and ran for a while. It was drained for oil and cleaned up by a service shop, but next season it did not run anymore. I got it running when I got it by cleaning the carburettor and everything seemed nice, but after 5-10 minutes it starts emitting white smoke from the exhaust and it runs at a much higher speed than when cool. I understand white smoke means oil burning, so I`ve checked the crankcase breather valve and tube. So my next thought is the piston rings or head gasket, but why would these break due to overfilling? Also I cannot understand why broken head gasket will cause white smoke. It does not seem to lack any power and it starts at first pull after primed. Any help would be much appreciated.
Take a look at this answer as this can be several different things, Also drain the gas before winter, I also drain the oil, change the air filter, check the vent on the gas cap and start fresh next year. I put new oil in my Lawn Mower now it smoking white
Overhead valve sleeves guides have been known to come loose and cause oil in piston chamber causing smoke
