MTD rear drive belt jumps off pulley

Old 07-26-10, 08:22 AM
Thread Starter
Join Date: Aug 2006
Posts: 9
Upvotes: 0
Received 0 Upvotes on 0 Posts
MTD rear drive belt jumps off pulley


I have a 1993 MTD 600 series 14/42 mower. Recently after shifting between reverse and forward the mower quit moving. I discovered the rear drive belt had jumped off the pulleys (between the transmission and idler) and was pretty chewed up.

When I put on a new belt the ride was very jerky both when accelerating and when braking. After a short test drive the new belt also jumped off the pulleys in the same location.

I do notice that the idler pulley, which sits on a bracket, appears out of alignment with the transmission pulley (by approximately 1/8 - 3/16"). I don't know if they are supposed to be exactly aligned or not.

Is this most likely the problem? (If so, how should I proceed? Can I just force the idler into alignment or do I need to remove the idler bracket and bend it, OR?????).

Old 07-26-10, 11:17 AM
31YTech's Avatar
Join Date: Feb 2008
Location: EveryWhere
Posts: 1,093
Upvotes: 0
Received 0 Upvotes on 0 Posts
Any way you need to the idler must be in-line with the trans pulley (force/remove arm and bend etc.).

Also check the front belt for wear and any flat areas in the V part of the belt, These can cause surging while moving and vibration/jumping of the clutch pedal.

Good Luck
Old 07-27-10, 09:52 AM
bontai Joe's Avatar
Join Date: Apr 2004
Location: Pennsylvania
Posts: 538
Upvotes: 0
Received 0 Upvotes on 0 Posts
I would also closely check that idler for a bad bearing, and any up-down looseness in it's bracket. They do have to be very close in aligment and even more important, that idler can not be cocked off at a different angle as that will throw the belt off for sure.
Old 07-27-10, 07:05 PM
Join Date: Oct 2007
Location: ontario,canada
Posts: 286
Upvotes: 0
Received 0 Upvotes on 0 Posts
the mtd manual also has adjustment procedures to follow after changing any drive belts

Thread Tools
Search this Thread
Ask a Question
Question Title: