Kohler CV490S Single Cylinder Smoking Blue

It is a 17hp kohler cv490s on a craftsman tractor. It is blowing blue smoke pretty good. I did a quick compression test and got 100 psi which I thought was acceptable. I have not done a leak down test yet but will soon. A funny thing happened as I was doing the compression test. I always remove the spark plug and turn the engine over in case there is gas etc on top of the piston. Well a lot of gas blew out of the spark plug hole. It blew across the garage. This engine does not have a fuel pump. I am thinking needle and seat problem. I also want to check the breather but dont know exactly where it is. Thanks in advace for the help. I appreciate it.

 

Well, I just did the leak down test and it seemed to pass. There was little if no leakage per the guage.

 

Could be a needle and seat problem, check/smell the oil if the needle/seat is failing the oil is probably overfull, if so, don't run it until you change the oil. Have a good one. Geo

 

Make sure the oil level is not over full. If so and it smells of gas, I would say you guessed right on the needle n seat.
The crank breather will be on the other end of the hose going to the air filter housing.

 

Well, I removed the valve cover and found a gas/oil mix laying on the bottom. The breather mesh is gas/oil soaked. It is encased in a tin box. How do I clean the breather assy -- hot water and soap ??? Does the breather come apart ?? The reed valve appears to be ok -- it doesnt seem broken. Should I add some auto trans fluid or marvel mystery oil to the oil when I change it to clean things out and then change the oil again after running a few minutes - maybe five to ten.

 

This engine has a brass seat. I replaced the needle and it still leaked. I next purchased the 12-521-03-s seat kit. This kit was announced in late 2009. Replaced the seat and also new needle -- no more leaks and no more smoke. I made sure all of the gas/oil mix was removed from the block. I also cleaned the breather with carb cleaner.