Voltage Regulator,
I'm not disagreeing with you, and I've rebuilt plenty of Kohler engines, and I agree that the K-series, single cylinder Kohler engine is one of the most durable engines I've ever seen. However, having worked on more than I can count, if an engine has been run to the point where the connecting rod breaks, everything I stated earlier is absolutely true! 9 times out of 10, when the rod breaks in half, the half attached to the crankshaft comes back up and breaks off the bottom of the cylinder skirt that protrudes down into the crank case. This engine is still rebuildable, and I've even rebuilt them myself, having the block bored, oversized new piston and rings, turn the crank, and they run beautifully. However, I'd say there's less than 50% of the engines in this condition, that will hold up under serious use, and I'd say that this condition is the reason for about 75% of the Kohler engines that blow up a second time. You're absolutely correct about rebuilding one for $150, and I'd say that this is the reason that the other 25% of rebuilt engines blow up a second time. Any idiot that can turn wrenches or kids working in their dads garage, can rebuild a Kohler engine. Trust me, I've seen it first hand.
I had a Cub Cadet 109 in my garage a few years ago that the guy just couldn't figure out what was wrong. The guy bought all the parts and paid some kid $100 to rebuild the engine. When he got it back the engine just raced and almost blew up the first time he started it. I opened it up and the kid had left out the governor control rod..... just a simple little part that's absolutely necessary!!!!!
I've also owned Cub Cadets that are 40+ years old and still running on the original engine, just using a slight bit of oil, and have plenty of power. Those tractors will likely run forever if you keep oil in them!
Anyway, like I said, if the connecting rod broke, the tractor was abused. Plan on putting a new engine in it!