If the engine runs great, what's the problem?
Beyond that, what have you already tried? Have you checked that the existing groove in the bushing is clear? I'd pull the crank, and clean both the crank and the bushing, use the tip of an X-acto blade to chase the groove. When the groove is clear, it should pull most of the raw fuel back inside the engine, a little oil or fuel out the front is normal. Even if it's excessive, the only real issue is fuel economy will be down a little. If the crankshaft rocks back and forth in the case, it's a bit more serious problem.
While you have it apart, visually examine the crankshaft, it should be smooth, maybe a little shiny, radial grooves - especially around the intake port can be an indication that the engine has ingested sand, dirt, debris that has worn the crank, and likely the bushing.
If it really bothers you, and a bit of cleaning and polishing doesn't clear it up, I'd junk the engine and use it for parts, or give it to someone that might not mind the wet nose. A new case will cost more than a used engine. A used case will probably cost as much as a used engine. It'd be further ahead to just get another one and move on.