I have a 2001 24 hp ohv Kohler. Sometimes when it is started it smokes bad and will continue to smoke. The next time it is started it may not smoke at start up or while in use. You never know when you start if it will smoke or not. Both head gaskets were replaced in 2003. It has 500 hrs. on it.

I just went through this with my 23 hp kohler command engine with all of 47 hours. Smoke on start up. It turned out to be a dirty pre-cleaner. Two problems resulted in my opinion 1) too low or no vacuum created 2) engine running very rich and diluting oil some. Cleaned pre-cleaner and smoke went away. After I made sure the problem was gone, I changed air filter, oil and filter.

thanks, i will try that