Small Engines (Lawn Mowers, etc.): Smoking and leaking oil out of exhaust, blown head gasket, check air filter

Question
I have a 16 HP Kohler OHV engine. It recently started smoking when i started it. It now appears to have gas and oil leaking out of the exhaust. The smoke appeared to be blue. It had plenty of oil and i service it well. Any idea what it is.

thanks jd

Answer
Hi  JD
has the air filter been installed all the time ?
you mentioned serviced it well,  did you perhaps over fill the crankcase with oil , ?
does the oil thats in the crankcase smell like petrol?  and very thin , dripps off the dip stick  very easily ?

oil may have been forced through breather and carb,   check carb for oil,check fuel needle valve for sticking and needle / seat for sealing  off the fuel flow -  check combustion chamber  for  oil as well  by removing plug , and turning engine over ( make sure no spark occurs incase   plug ignities  fuel outside of engine when turned over , if its been wet-sumping),to clear anything that may or may not be in combustion chamber,  check air filter for oil on the element!

could also be a blown head gasket , has the unit been low on oil @ any stage  and overheated ?
it also could be a breather system not working / or blocked / restricted , building up pressure forcing oil past rings, breather reed are under rocker cover on the cylinder head  

here is website for parts breakdown

http://www.partstree.com/parts/?lc=kohler_engines

select  model and spec from the list that matches your engine eg ch/cv5 - 16, then  cv16
then select spec number from list

have a look and let me know what you find , i will try help further

cheers paul  hope it helps