2019 Carlton 7015 engine belt jumping.

[Geterdone]

Hello all, my Carlton stump grinder just started this problem, under heavy load (grinding big passes) I hear a load thumping sound. I tore into it in the shop and the only thing that makes sense to me is the engine belt is hitting the guard. There is some marks in the inside of the top guard. I have not noticed the wheel slipping, which I have had before and then tension ed the belt. Is the belt jumping up and hitting the guard a sign of the belt being loose?

 

[gorman]

Hello all, my Carlton stump grinder just started this problem, under heavy load (grinding big passes) I hear a load thumping sound. I tore into it in the shop and the only thing that makes sense to me is the engine belt is hitting the guard. There is some marks in the inside of the top guard. I have not noticed the wheel slipping, which I have had before and then tension ed the belt. Is the belt jumping up and hitting the guard a sign of the belt being loose?

I’d first make sure your jackshaft pulleys are tight

 

[Geterdone]

I’d first make sure your jack shaft pulleys are tight

Yes they are all tight and still lined up. belt is in good condition and the belt housing is clean of all foreign objects. I tightened the belt slightly making sure it is not to tight to cause bearing damage. I also used belt dressing and so far I have not heard any noise. Still curious to hear any other ideas on this.

 

[Bigstumps]

I would bet it is the PolyChain. If it sounds like a banging this is what it is. You have to move the cutter wheel bearings to tighten it. Make sure you loosen them slightly then turn the adjustment bolts the same amount and retighten the hold down bolts. They aren't going to have to move much. Use a Gates sonic tensioner to get it adjusted just right - go to the tight spec. Heard this sound many times - it is the PolyChain ratcheting.

Let me know what you find

 

[Mowingman]

While you are at it, make sure the chaincase for the poly chain is nice and clean. Just a little buildup of dust/chips will cause the poly chain to act up.

 

[Geterdone]

I would bet it is the PolyChain. If it sounds like a banging this is what it is. You have to move the cutter wheel bearings to tighten it. Make sure you loosen them slightly then turn the adjustment bolts the same amount and retighten the hold down bolts. They aren't going to have to move much. Use a Gates sonic tensioner to get it adjusted just right - go to the tight spec. Heard this sound many times - it is the PolyChain ratcheting.

Let me know what you find

Thank You, This is also what I decided after being on the job site with my crew and listening to the sound.

 

[Geterdone]

While you are at it, make sure the chaincase for the poly chain is nice and clean. Just a little buildup of dust/chips will cause the poly chain to act up.

Thank you The guys clean this area out at least 1 time per week or more depending on the jobs.

 

[iowagold]

also make sure the bearings are in good shape!!
as a trained vib tech this is one of the things we see that will shorten the life of a bearing..
galloping belts.. and it is an oscillation or harmonic thing..
so engine speed can be an issue for this to show up as well as load..
also make sure the pulleys are clean and not worn with abnormal wear..
if they have a worn lip on them it will try to grab the edge of the belt and make a vibration or oscillation..

the best way to see the action is with an adjustiable flash rate strobe...
some of those good strobes are calibrated by rpm!
yea I have 2 of them that I use when looking at large horsepower fan setups with 5 belts or more
that run 7/24.. you can use the strobe as an inspection tool to see frayed or cracked belts as well as the belt action under load.

cool tool indeed!!

use the best quality of belt you can fit on the machine
watch the numbers as some part crossovers for some belts are wrong..

 

[Geterdone]

sorry with everthing going on forgot to let people know that I tensioned the belt and the problem went away. did not have to tension it very much.

 

[jimmycrackcorn_1]

Greetings - Jimmycrackcorn here from Myrtle Beach! Proud owner of a 2015 7015TRX . Question: do any of you have experience with drive belt manufacturers? I see many after market belt manufacturers out there and I wonder if the less expensive belt is worth it; or just purchase from Carlton. And feedback is appreciated!