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!
There is a oil seal on the top, under the flywheel. It can be leaking. or a valve cover gasket will also leak and show as smoke on top when shutdown/ As for replacement, you would have to go to a different series of engine.
Flywheel removal. link above.
Service manual link above.
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