Cub Cadet 1811 belt problem
 

I've inherited a BIG problem. My sister's husband passed this past winter. He did all of the grass cutting chores so now I have to do it. I've never had any experience with a tractor being a city boy. My problem is the belt...it keeps coming off the pulleys. I thought it was a tension problem. I see a diagram on the front frame where the right pulley is adjusted with a nut to align the left pulley to a small notch to the frame. I have to have the adjusting rod on the right pulley almost all the way in to align the first small notch with the frame like the diagram. That doesn't seem right. After adjusting the belt I start the tractor. Lower the cutting deck and start cutting. I might go 30 feet or then I might go 300 feet before the belt comes off. I notice that the left pulley that is spring loaded bounces back and forth something fierce. There seems to be a lot of tension on that left pulley but I tried wrapping a bungee cord around the frame and the pulley just to get a little more tension try to keep the pulley from bouncing so much. Didn't help. The pulley is in good shape. Spins freely and is not loose on it's mount. The belt is in good shape. Is that left pulley supposed to bounce back forth so violently? I had to cut her almost 2 acres with a 22" push mower so I'm hoping that you guys can suggest something for me. Thank you.

This may help......... Belt Alignment

When you say adjusted almost all they way in, do you mean the nut is almost bottomed out? If so it means the belt is stretched to it's limit and you need a new belt. The spring loaded pulley bouncing around erratically sounds like there is not enough tension because the belt is stretched too much. Hope this makes sense. Also make sure the pulleys on the deck are greased and are easy to turn by hand without the PTO belt attached. If any pulley feels rough as you rotate it, you may have a bearing going bad or trying to lock up when it gets heated.

All good info so far. I will add to check the mule drive pulley bearings. The only time either of my tractors had a pto belt issue, it was because a mule drive pulley bearing was toasted. I replaced the offending mule drive pulley/bearing, new belt, no issue since on either machine.

Bill

Cub Cadet 1811 belt problem
 

Is it normal for the spring loaded pulley on the left side from the front to bounce back and forth violently while cutting. I have the tension set to the first little notch to the frame using the right side threaded rod like shown on the from diagram on the frame. Even bought a new belt and still the same. The belt keeps coming off the pulleys. The pulleys are in good shape, not loose or worn out. The spring seems to have good tension but I added stiff spring to the pulley bracket and the frame for more tension but still the belt keeps jumping off. While walking along side the tractor while my sister is mowing I can see that pulley jumping back and forth something fierce. That doesn't seem right. My sister's husband passed this past winter and used to take care of things but now I have to and I have never had any experience with tractors. Any thoughts as to what I might try? Thanks a bunch.

You have several threads on the same subject. If you have an update, post back to the original thread and not start a new one. :beerchug:

(A) Are you using a genuine Cub Cadet Belt...??
(B) How about some pictures of the belt and the mule drive pulleys..??
(C) Did you align the mule drive pulleys per the link provided...??

The diagram I posted below will show the three notches on the adjustment/lock out lever. It sounds to me you are adjusting you belt tension to the very first notch "C" next to the front frame on the tractor. If so that is the notch that means you need to tighten the belt until the middle "B" notch is aligned with the front of the frame. The large notch "A" is used to push the mule drive pulley back and lock it into position so you can easily take the belt on and off.

Attachment 65614

No, that's not right. Look in the pulley sheave and see if there's a rock or a stick wedged in the V groove causing the belt to jump.

My apologies on my double post. I didn't see my post and thought I had done something wrong so I tried again. I did adjust the belt to notch to the frame. The adjusting rod has to be almost all the way in in (no threads left) order to do the belt adjustment. I know that can't be right. The pulleys are all in good shape. The belt that is mounted on the tractor now is stamped with "B90" with no brand name on it. I'm wondering if my sister's husband used the correct belt because I was talking to my sisters neighbor today and he told me that her husband was having trouble with that belt coming off the pulleys. What would be the correct size needed here?