Many types of paint inside the engine could be a bad thing... However, epoxy hardens very well, adheres extremely well, and is completely non-reactive with oils and fuels. This is the exact correct product for properly sealing inside your crankcase. Among the benefits are easier and much more thorough crankcase cleanouts, better ability to inspect and recognize contamination problems as they develop, prevention of any oil seepage due to porous areas or casting flaws.
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