Cub Cadet 2518 eating belts.

[Kmicah40]

I have a Cub Cadet 2518 that I’ve been working on for a neighbor. Think I have issue with mower deck or PTO or both. At times when engaging the PTO to start mowing it will have a belt come off and before you realize you have a problem the belt is destroyed. I’ve noticed when engaging the PTO that the belt jumps pretty bad. Each time the belt comes off it is the front lower left side pulley if you’re looking at the front side of the tractor. When the belt comes off it lodges between the pulley and the tractor frame. If the belt comes off the mower deck it normally is at the spring controlled idler pulley and belt gets lodged under the pulley. I’m not sure how the PTO is supposed to engage. It appears that when turning on it engages immediately and you can see the belt jump and getting loose before the spring tension has chance to work. All the spring tension seems to work great once you have successful mower startup. In the last 5 weeks we have replaced 3 PTO and 2 deck belts.

I’m thinking the PTO is the problem and not the springs. Is a good PTO supposed to engage gradually or almost instantly? Is there a way to make adjustments to the PTO so that it will slip a little when turning on giving the springs a chance to work?

Appreciate any advice you might have.
Thanks.
Larry H

 

[mikester]

slow the engine speed before engaging the PTO

strong clutch means less slip and longer clutch life

 

[Carl_NH]

The 2518 PTO drive has spring tensioner on the double spindle on the back of the deck and if that plate assembly doesn't move or is corroded this will not allow the belt to tension properly. Also I think there is adjustment in the deck hangers on this model?

Then the belt itself, I use the blue belts on my CC and some slippage is good on start up which prevents the whipping effect - it the belt grabs quickly this can cause it to pop off the pulleys. You might want to try some belt lube on the PTO drive belt to see if this improves it.

The fact that you have replaced three belts in a short time means something is out of alignment, deck, pulleys etc. You can also check out a Cub Cadet forum Only Cub Cadets - there are a lot of knowledgeable guys over there.

 

[Kmicah40]

The 2518 PTO drive has spring tensioner on the double spindle on the back of the deck and if that plate assembly doesn't move or is corroded this will not allow the belt to tension properly. Also I think there is adjustment in the deck hangers on this model?

Then the belt itself, I use the blue belts on my CC and some slippage is good on start up which prevents the whipping effect - it the belt grabs quickly this can cause it to pop off the pulleys. You might want to try some belt lube on the PTO drive belt to see if this improves it.

The fact that you have replaced three belts in a short time means something is out of alignment, deck, pulleys etc. You can also check out a Cub Cadet forum Only Cub Cadets - there are a lot of knowledgeable guys over there.

Carl thanks for your reply. I agree with everything you say. I did a complete tear down of the deck and cleaned and lubed all the moving parts. Replaced the bearings in the double pulley spring tensioner. Removed each belt pulley and polished were the belt rides, on my old engine lathe. This mower had sit idle for a few years and had some rust on the pulleys. Thing is if when turning the mower deck on it runs as it should you can mow without any issues. Occasionally when the PTO is engaged that is when one of the two belts will come off of the pulley. It only takes a few seconds if the belt gets wedged between the pulley and the frame. It starts ripping the belt to shreds. I’m going to get some belt lube and give that a try. That might work. Main reason I thought the PTO was the problem is my own 2 mowers when starting the mower deck it takes 2 or 3 seconds for the deck to get up to speed. Don’t see the belt jumping like the mower for my neighbor.

 

[Carl_NH]

Silly question but are the belts OEM or have you tried a shorter PTO belt? Reasoning is maybe the initial clucth engagement is causing the belt to slip off that idler pulley and a shorter belt would be tighter? Also you probably troed slow speed start too - does that change anything?

 

[Kmicah40]

Silly question but are the belts OEM or have you tried a shorter PTO belt? Reasoning is maybe the initial clucth engagement is causing the belt to slip off that idler pulley and a shorter belt would be tighter? Also you probably troed slow speed start too - does that change anything?

I sprayed the belts with a belt lube spray and that seems to take care of the problem. Now when engaging the PTO it is a smooth transition. The belt does not jump around. The belts used are not OEM belts. Using the belt lube will probably extend the life of the belts as well.

 

[Carl_NH]

Excellent - but belt lube is temporary - maybe 3-4 hours or a few cuts - the issue with belts is rubber/strand content vs stranded aramid fiber content belts - the rubber will grab immediately - the stranded fiber ones tend to slip vs grab.

 

[Kmicah40]

Excellent - but belt lube is temporary - maybe 3-4 hours or a few cuts - the issue with belts is rubber/strand content vs stranded aramid fiber content belts - the rubber will grab immediately - the stranded fiber ones tend to slip vs grab.

Agree, I told neighbor should spray belts every other mowing.