Check the engine over and look for spots where fuel has leaked. Your best bet is to clean it throughly and loosen the carb bolt, then push the carb down snug against the engine block and re-tighten.
Run the clean engine and inspect it once the issue starts again. Look for fuel.



I'm having a simular issue on my .12 cv-r. It's leaking out the rotary part of the carb. It probably needs new o-rings.