Z445 john deere breaking mower belts immediately when pulling pto swich, what could cause this?

The actual clutch mechanism is right underneath the mower on the pulley system

Take a look at this..

http://manuals.deere.com/cceomview/omm163777_k0/Output/OMM163777_K011.html

and scroll down to the section you need...

Here's the Owner's Manual - with belt diagrams:


http://www.homedepot.com/catalog/pdfimages/5b/5bef7eb2-6221-4934-98cd-5fcaaf2ac9eb.pdf

Depending on which type of PTO you have the problem could be simple to diagnose... if you have an electric PTO, you may be dealing with a bad switch... if electric, you should have good tension on the belt at all times. If it is a lever that you push/pull to engage the blades, then it would seem that the tensioner pulley is not applying the required tension on the belt... could be a broken spring or a worn/slipping belt (not enough tension)... hope that gives you somewhere to look into...

how is the belt tension

Hi, check your belt tension, check all idler pulleys and drive pulleys for free rotation with the belt off and finally check that the belt is not bottoming out in any of the drive pulleys. If so, replace the belt. The blades should come up to speed imediately wether hot or cold and it sounds like your belt is slipping in one or more of the pulleys which drags the motor revs down until it grips. Regards Phil.

Maybe the drive belt is to small and pulling on the assembly, and in turn pulling enough to break the bolt. probably is fine when idle, but under load the condition changes, causing tension to be applied and snapping the bold. That would be the first place I would look.

I have also had other bolts come out of other assemblies and everything ran fine. Until one day when it didnt and belts snapped and so did bolts as and my transmission. It wasnt a good day. So check your belt alignments, mower deck bolts, spring placement, rear end bolts, etc. Good Luck!!

not trying to insult your intelligence, but did you make sure the belts were installed properly.it does happen to the best of us..good luck

CK THE SEAT SWICH OR THE BRAKE SWICH ONE OFEM IS BAD