Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!
Does it still start and run ok? If it does, I would do nothing, as it is not unusual for oil from cylinder, or just black exhaust goo to come from muffler.
May have oil leak on the engine sump! Showing up around exhaust system. Sounds excessive by the 12 inch pool. Oil would smell of fuel if it has fuel in the oil from carburetor. Or overfull.
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