Something is definitely wrong. Wheel Horse runs the same setup and you can run them all day long in the heaviest grass with no issue. Something is either too tight or it’s mis-aligned.

Ex-Mark commercial mowers also use this same style belt configuration. They too can run all day in any condition without worries of overheating belts.

 

I bet a spindle bearing is bad. Sometimes they are not noticed unless under load (belt installed). Can the shaft be disconnected or put in neutral so you can try to rotate the belt by hand to see how hard it is?

 

My first thought as well...

 

If it is not raining this coming weekend, I intend to pull the deck off and check all the spindles, pulleys, idlers, etc. And I intend to grease everything that can be greased.

I didn't say that the top of the deck had a lot of grass clippings around everything, but I didn't think it was enough to cause the overheating.

I appreciate the input so far, I also believe something is hanging up somewhere.

 

https://ww2.gates.com/IF/facts/documents/Gf000273.pdf
You'll find the problem capt. I have no doubt

 

I would start with checking all the v- belt sheaves for wear. The sides of the belt is what drives the sheaves , the sheaves can get worn along the sides over time causing slippage. Slippage of the belt causes heat buildup, destroying the belt. Normally a worn sheave is dished out on the sides. It only takes one worn sheave to cause issues. Also the use of heavy duty Kevlar belt may help.

 

I'd check the clutch setup and make sure the clutch is actually working the way it should.
With our Wheel Horse 314 I do believe the deck drive belt gets somewhat tighter when you lower the deck, so I would check belt tension with deck lowered.

 

If a bearing in a spindle is going bad that housing will often be a different temperature . No thermometer needed , touching with the hand to compare with the others will usually suffice .

 

Sounds similar to this set up here. This shows the adjustment the mule drive should be at. There is a spring that holds the tension and if it has gotten weak in the last 40 years the belt could still be slipping. Actually 2 springs, the coil spring and pull spring on the tensioning screw. Check the mule drive pulleys to make sure the bearings are not bad. And then yes, check the deck to make sure there is not an issue putting a high load on it.

 

Something is obviously wrong (unless this is a known issue since day 1 for this type of mower, which it doesn't sound like it is). I hope you can fix it for him. If not I would definitely go to a a different dealer or to an independent repair shop. The original dealership is either terribly incompetent or scammers of an elderly man.

 

I appreciate all the information given so far, and this will probably become a case of "if all else fails, read the instructions". My friend does have the manuals that came with his tractor, and I just didn't have enough time to read through them in detail last weekend.

But if I did get something from all this discussion, belt heating is caused mostly from slippage. The mule set-up does not have any adjustment, the belt tension is set by a big spring pulling on the moveable deck pulley/sheave. There is a long lever to relieve tension to remove the belt/drop the deck, and to my unfamiliar knowledge, it did put a bunch of tension on the belt (based on deflection when I pushed on it, similar to fan belts o a car). But I did notice that the front link on the deck is adjusted almost all the way forward, so I "think" I can move the deck back for more tension if that is part of the problem. Again, something to look up in the manual about adjusting the deck.

I haven't dealt with his dealer, it is the same Kubota dealer that I wasn't impressed with when I was tractor shopping. I ended up with a JD from a different dealer. So I don't know if the service is just incompetent or not. In any case, they have not solved the issue and running it for 5 minutes after servicing doesn't address my friend's complaint.

I'll start with the basics and go from there.

 

I had a 50" deck on a 318 that would regularly eat belts. It turned out the the tensioner bearing was bad. Replaced the tensioner assembly and never looked back.

Dave

 

I had 2 Cubs that worked this way never an issue mowing a few acres at a time. Mis aligned or bad bearing.

 

If that dealership service department actually told this fellow that there's nothing wrong with his mower then they are either unbelievably lazy and ignorant, or are contemptible bastards that are making easy money by repeatedly conning a trusting old man. No mower ever built should be considered "okay" to burn up drive belts every few weeks! Especially a venerable brand like Cub Cadet. My GT235 is almost a quarter of a century old, and I've only replaced my primary drive belt ONCE! Those thieving scum should all be flogged, then tarred & feathered.

I am with the others here who suspect one or more worn bearings as the likely culprit. But if you do nothing else, find another shop for this man to take his tractor to. See if your local JD shop will work on it or, at the very least, direct him to a place that is more trustworthy. And once this is resolved, report those shameful crooks to the BBB. And be certain to post a scathing review of their gross ineptitude and malicious chicanery on Google, where those vile weasels will be unable to hide or delete it. Sorry for the outburst, but that's always been a very sore spot with me. I despise filth who prey on the weak, the innocent, and the elderly. A-hole businesses like that give ALL dealers & service shops a bad reputation - even the good ones - and they deserve to be cleared out... or shut down.

 

one more thing I have found to cause one to get hot is for the belt to be routed wrong and rubbing a guide or other piece of metal but not hard enough to stall the mower. you would have to look and sight alone a straight line for all the belt directions while on the mower and determine if there was a slight bend in the belt as it goes from pulley to pulley. along the same lines a pine cone, piece of twig, or a gum ball lodged in the wrong place can cause friction heat.

 

No update yet, though we had time to visit our friends over the weekend, I didn't have time to look at his Cub. His other tractor, an old Ford 1000 was stuck out on the other end of his property. He had shut it down and couldn't get it restarted. That is another story for a different thread.

I will report back when I find something.

Thanks for all the advice so far.

 

Update
I had some time to work on my friend's cub cadet yesterday. I removed the deck, there was a lot of dried grass clippings on the top, not enough to cause any drag. Removed the deck belt, blew out the grass, scrapped the underside and checked every spindle and pulley. Nothing out of the ordinary, all without any side play and smooth. I forgot to bring my grease gun, and he couldn't remember where his was ... as we figured that during his last yearly tune-up, they "should have been greased" ... so we decided to leave that to the next time. As mentioned, nothing rough when turned by hand, same with the deck belt installed.

The drive belt was in good shape. After putting everything back together, I mowed for about 30 minutes on some "light load" grass and checked the belt temperature. IR gun said about 150 F, belt was more than warm, but not burning hot by any means. Then I mowed some heavier grass, for another 30 minutes and checked the belt temperature again. This time temp was up to about 175 F, hotter for sure, but not screeching hot that would cause the belt to burn up (in my opinion).

The electric clutch at the front of the engine was much hotter, probably more than 240 or 250 F (I don't remember the exact reading, may have been even higher) when we first turned off the mower. I was wondering if the clutch was dragging when energized as I noted that the drive pulley is tight to the clutch (a pin on clutch frame stops rotation) when everything is off (I assume braking action when turning the PTO off?). Does anyone know how to check the clutch? If energized, it should be tight on the drive shaft and if not energized, it seems to be tight on some braking material? If I have to take it apart, I can, but I'd have to plan some more time for that.

Later yesterday, I mowed my own lawn, old Wheelhorse with a similar mule drive. My belts were a lot cooler after my 90 minute mow. I didn't have my IR gun with me, but just holding the belts, it felt a lot cooler. Note that the Cub Cadet belt is lot bigger than my Wheelhorse. I don't know if that tells me the load difference between different decks?

So there is a difference in temperature, but is that temperature too hot?

We talked about his normal cutting habits, it seems he cuts grass much higher than I do and maybe the high loads his mower sees is causing the higher temps.

We laughed, and he said that he may try mowing in 30 minute intervals with a 15 minute water break in between. He's in his mid 80's so having more breaks is a good thing.

 

If everything else mentioned checks out, then look at the pulleys for wear. (This is an "OLD" machine) A belt on a worn pulley will slip. And slip is heating. There are belt profile gauges made of plastic (inexpensive) to check for wear.

 

Did you get this one figured out? I have a JD rider that broke 2 belts within the first 20 hrs. For the life of me I couldn't figure it out.

I just releveled my deck and the final step in the owners manual states the front of the deck should be 1/8 - 1/4 LOWER that the rear. I just ran my mower for a few min and the pulleys are definitely cooler to the touch. I never checked the deck on delivery from Lowes.