I instruct all my crews to run approx. half way up, engage blades the run to full. To disengage, we turn throttle down half way, then disengage. Also, we NEVER run full when engine is not under resistance such as when transporting to and from trailer. Sorry you guys had such bad luck on the Kohlers I've had nothing but great performance out of mine. One is a 20 hp Magnum, with about 1500 hrs. on it on a Gravely Promaster 300 tri rider and the other is a new Kohler with 26 hp and the fuel injection set up. That is on an Exmark Laser EPS. All other motors are Briggs and Kawasaki (Liquid cooled-- Lazer also).