why does gas mix wiyh the oil on a 15.5hp kohler engine on a craftsman lawn mower

gregg, July 2004

not sure why the gas is mixing with the oil on my riding lawn mower

brian lawton, June 2010

The needle in your carb is not shutting tight so the gas is going up and through your carb into your intake valve and leaks down your piston cyl into your oil. Do not try to start your engine it can cause a lot of internal damage. Get your carb fixed by replacing the needle and seat. Drain and put in fresh oil, then try to start. Good Luck

JOHN at Rona, September 2004