I have fought this thing for a long time now and just when I think I have found an answer another stumbling block appears. I have at this time been trying to repair an older Lowe's rider, I believe MTD. manufacture. These decks as you know are spring loaded, that is to say as you lower the deck, the deck is moves backward and the drive belt for the blades tighten. When returned to the highest postion or off notch, the belt slackens and the rotation of blades stop. Is the belt the only thing that adjust this function? I have looked and played with every thing under these head beating problems. I know if the belt is to long it won't engage till the lowest point is reached and if to short the blades run all the time. If any one has an answer for this crazy set up .... PLEASE tell me the secret. thanks for any and all. I know that a stick of dynamite is good.