Spent ANOTHER day in the bilge with the Kohler 6.5CZ9I MUST mention that the CZ is different from the others! I have bought parts for the 6.5GZ and they are different!) I have been looking for a governor spring forever, as they are NLA. However I found 3, and now own them. Genset was hunting all over and surging. I should have replaced the spring when I had the starter out, but it was not a bad replacement if you have the right tools, long nosed pliers and fingers you dont mind cutting. I went to replace the heat sensors, but of coursee different as they were for the GZ. (If anyone need a couple I will make a deal on them!) SO I removed the old ones and cleaned up with a wire brush so ther is good clean contact. Next the 20UF capacitor was replaced with the upgraded 25UF. Started her up and bingo. RPMS were WAY high as the new spring was tighter, putting out 135VAC and spinning at 3800. Factory states 3600 under load, and 3750 with no load to hit 60 cycles. EASY governor adjustment to dial in at 3600. SO far, she is running smooth, no surging and has not done the shut off thing as it was doing. Here are a few photos of my (so far) success.