Thanks for the info. I found the problem the next day, when i looked at the clutch more carefully. The plug on the clutch was melted a lil bit. I removed the clutch. The top bearing had lost some balls and i could pull the inner race out easily. Must of got hot, or just wore out. Luckily it still worked and didn't do any major damage to the shaft. The owner told me the mower gets rained on all the time. One of those things where i was going to get it running, after it sat idle for a year. The first thing i checked was the air filter. It was so loose, that i could pick the filter up about a half of an inch. The air filter and the air box was also slam full of grass and dirt. Needless to say i had to clean the carb. Luckily it didn't burn the rings up. It ran good. I didn't find out how old this unit is. I've been curios how good Kohler engines are. Once again, thank you.