hope I didn't throw $ out the window. I came across a 18hp Kohler command side shaft out of a Cub tractor. condition unknown but appears to have compression. They seem hard to find in my area used so paid 300 for it. does need a muffler but I figured would need some fabricating there anyway to get it to fit behind seat in Case 1816. I also had offered a guy 200 for a Honda gx620 (20hp) before I saw the Kohler- if he accepts I'll have two engines to choose from. The cost is still in ball park just for one. Downside is the Honda has taper shaft but I'm willing to try to figure that out as I Love the way big Hondas run (got another on snowblower)- If the kohler runs and don't smoke.. or either engine far as that goes- think it is ok to use it without a re-build? I once bought a 392 Hemi and tore it down- only to wish I hadn't as it was flawless inside (never got it back together)