I am assuming you have an older rear engine rider john deere 68 and not some newfangled thing. If it has an 8hp briggs and stratton motor and a manual transmission, then we are on the same page. Now as to your problem, it could be a couple different things. The drive belt could be loose between the motor and the transmission or it could be improperly tensioned. Get a new belt, clean the underside of the frame, tighten the belt idler. You also may have lost the half moon key out of the transmission pulley. Take that pulley off and make sure the key is properly in place. Lastly, you COULD have a transmission problem. Not very likely though, these peerless transmissions are pretty tough. You can open the transmission up and tinker on it, but if something is wrong with it, it may mean a major overhaul. If it is seriously screwed up inside, it would probably be cheaper to go to a salvage yard and look for an old 68 that you could pull the transmission out of. Hope this helps!
Jon
March 2013
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