I have a Kubota Z421kwt with a Kawasaki Fs730v engine that has about 100 hrs on it. It was surging at high idle. I’m currently recovering from a broken ankle and my wife was going to mow the lawn for me. A friend of ours looked at it for me. He said that he adjusted the idle speed screw and the surging went away. I don’t believe that screw should of been messed with. I would like to put it back to factory position. Does anybody know how many turns out the screw should be. I haven’t tried to start it since. I don’t want to cause any damage.