I have a Scott lawn mower with a 17.5 H.P. Kohler engine on it. The oil gets contaminated with gas. I have changed the oil but it gets gas in it again within an hour or so. Hopefully there is a simple cure for this.Can you tell me what it is? Thanks, Bill

Hi,
Replace the fuel pump; matters none whether it is vacuum or mechanically operated, there is a hole in the diaphragm.
Peace,
Clarke