RZT 50" deck belt comes off or snaps randomly!

[Dan Fitts]

Hi, i own an rzt 50 zero turn mower. Have had problems with my belt either snapping or falling off. I have people and myself thinking that maybe because at full throttle, when i go in reverse and it stops the deck, going back forward kind of jerks it around. Not sure though. Please help!

 

[1811Cub]

I would verify proper tensioner function. Also make sure all bearing assemblies are smooth and not worn out. Also, always use OEM belts. NONE of the aftermarket belts seems to last as long in my experience.

 

[spndncash]

if you have ever changed any pulleys make sure they are correct size . the v of the belt should never bottom out on a V pulley, idlers that run on the back of the pulley are different but make sure if they were replaced the proper spacers are in for alignment. check the alignment of all the pulleys...this along with everything said above.

 

[Mark Evans]

I would verify proper tensioner function. Also make sure all bearing assemblies are smooth and not worn out. Also, always use OEM belts. NONE of the aftermarket belts seems to last as long in my experience.

Not only smooth but with no sound shows grease is in them !!!!

 

[Wallace Fiala]

I myself would never engage the pto with the throttle running more than a bit over an idle. Further more disabling that awful backup feature was the first thing I did.

 

[Wallace Fiala]

I myself would never engage the pto with the throttle running more than a bit over an idle. Further more disabling that awful backup feature was the first thing I did.

 

[Wallace Fiala]

Oh, forgot to mention, my 12 year old RZT-S still has the original belts !!!

 

[Dan Fitts]

if you have ever changed any pulleys make sure they are correct size . the v of the belt should never bottom out on a V pulley, idlers that run on the back of the pulley are different but make sure if they were replaced the proper spacers are in for alignment. check the alignment of all the pulleys...this along with everything said above.

So i verified everything was the correct size. Did buy the pully repair kit that comes with all of them except for the one that swings with the arm and the one in the back thats driven by the motor. Still having the same problem. The belt that came with the kit shredded and the good belt from oem i got cleanly snapped. Not sure if i have to replace the pulley, spring, and arm? Process of elimination here. Im just lost with this thing!

 

[Dan Fitts]

I would verify proper tensioner function. Also make sure all bearing assemblies are smooth and not worn out. Also, always use OEM belts. NONE of the aftermarket belts seems to last as long in my experience.

Yeah, i have been using top of the line belts and have gone through quite a few. Bought a replacement pulley kit and still snaps belt. Process of elimination points to either the pulley that doesnt come with the kit. The arm it swings with, or the spring? Im at a loss.

 

[mfrade]

Have you verified the spindles and idler(s) are free?

 

[Dan Fitts]

Yes i have spun all of them. None of them bind up or anything. I mean i will double check tonite after work, but its just mind boggling

 

[Dan Fitts]

On the idler that attaches to the arm, there is a small clip piece that comes up on the side of the pully. When my belt first snapped a couple times, i figured the belt needed to be inside the clip. It never was. Not sure if that clip is supposed to keep the belt in, but it snapped with it inside as well.

 

[Dan Fitts]

 

[Dan Fitts]

This is the pulley attached to the arm with spring. I just noticed the wheel doesnt spin. If im not mistaken, all the pulleys should spin correct?

 

[mfrade]

Yes, they should all spin freely, I have a relative with that same mower. And just weeks ago I had to replace the middle spindle and found that pivoting idler wouldn't.. it was frozen under the pivot. That clip had a couple "bumps" that acted as an index to hold it in the proper position. It's close where it is in that picture. It keeps the belt from whipping off the pulley(s). It fits very close to the pulley. But verify that idler pulley is bad and while the deck is off - check the blades for balance & sharpness.

 

[Dan Fitts]

I bought all new blades and they were part of the spindle and pulley kit. That one pulley wasnt included in the kit

 

[Dan Fitts]

Went to check if that pulley would spin by hand and it would not.

 

[Dan Fitts]

Do you happen to know what the part number for that pulley is. Im having a tough time locating it. Would i need a new spring as well?

 

[spndncash]

go to the cub site with your model number and the pulley will be listed there.
https://www.cubcadet.com/en_US/serv...3Mo-Lqu5KYIPzUavBgSx4bsaAgZhEALw_wcB#diagrams

 

[Dan Fitts]

So essentially its the same idler pulley as the others?