I have a Craftsman 5HP tiller with reverse (Model# 917.299450) Searspartsdirect link (http://www.searspartsdirect.com/partsdirect/retrieveModelActionHome!retrieve.action;jsessionid =DSLfcSK-4WVmBeiPlN-bVg**.shcapp3105?modelNumber=917.299450&pop=flush)
I got the tiller from someone else and it was purchased in 1981 I believe. So its an old old tiller but it still runs and does the job.
I replaced the forward motion v belt. The one I put on broke so I replaced it again.
I now have two problems.

1. The tines rotate all the time now. When I put the tine control in the running position the tines run faster. Releasing the tine control does not stop them, they keep turning slower. I have adjusted the tine control cable down but that did not help. So I am stuck now. I am not sure what is causing the tines to run all the time.

2. the forward motion v belt slips off the idler pulley and falls between the idler pulley and the engine when the tine control is in the running position. I am pretty sure the idler pulley needs adjusted but can't figure out how. Either that or the engine pulley needs adjusted so it is in line with the transmission pulley. I can't figure out how to adjust the pulleys.

Thanks in advance and let me know if I need to provide different details.
And FYI, the manual does not give details on how to do these things.

Bet you got the wrong belt and it's grabbing.

If you want to get it locally. Go to DAYCO.COM - MARKIV Automotive Aftermarket (http://www.dayco.com) and lookup the Dayco part number. Then, armed with the Dayco number, go to your nearest NAPA auto store. The should be able to hook you up. The correct belt is essential.

I can't tell much from the diagram either. What I can tell you is that the engine is likely mounted in slotted holes and provides one of the adjustments.

Bet you got the wrong belt and it's grabbing.

If you want to get it locally. Go to DAYCO.COM - MARKIV Automotive Aftermarket (http://www.dayco.com) and lookup the Dayco part number. Then, armed with the Dayco number, go to your nearest NAPA auto store. The should be able to hook you up. The correct belt is essential.

I can't tell much from the diagram either. What I can tell you is that the engine is likely mounted in slotted holes and provides one of the adjustments.

Thanks. I will double check the belts.