Mower Information: 2005 Super Z 60" Kohler 28 EFI Purchase date: 5-03-05 Model # 927053 Serial # 05032381 Warner Clutch Homeowner use only. Maintained meticuously. 402 hrs. At approximated 350 hrs. original PTO switch stopped engaging clutch, replaced switch and new switch lasted maybe 20 hrs. Installed 3rd switch and replaced pigtail. Yesterday 3rd switch also stopped. Talked to a mechanic and was told to unplug pigtail and check clutch with an ohm meter. I can borrow an ohm meter but I have never used one. Will someone please explain the procedure step by step so I can check the clutch to let me know if it might need to be replaced. I was told by mechanic that clutch might be grounding back through motor, I don't understand what he was saying. Can someone please explain? How can a clutch with only 402 hrs. need replacing. I cut 2.5 acres twice per week, so I'm never taking off much grass and the mower is never under a heavy load. I did a search and read several post about switch, pigtail and clutch issues, so I'm aware that others have had similiar problems. My main concern is how to use an ohm meter and what will it tell me. Thanks for the help.