Strange belt failure

[dnw64]

Never seen this before. It's on my Caroni flail mower which I've had almost 2 years.

Before heading out on my first pass of the year I greased all the bearings, and while greasing the main bearing at the end where the belts are I saw what looking like a piece of belt sticking through one of the ventilation louvers.

So I took the cover off and two of the belts were shredded. OK, not great, but whatever. It has probably 20-30 hours on it (don't really know) and maybe the factory belts were junk. And maybe that still is the main problem, but what I saw upon further inspection is that chunks of the inner part of the belt were still stuck in the sheave. Like, really stuck. Couldn't get them out with my fingers - had to use pliers. The only explanation I have come up with is that they got hot enough that, when stopped they melted to the sheave and at the next use pieces got ripped out.

Any other thoughts/suggestions?

 

[Menagerie-Manor]

Had the same issue with my Flail mower last week, Chinese crap belts were less then 3 hours old and just basically melted. I had to use a wire knot brush on the angle grinder to clean the cooked remains out of the pulley. Took the belt down to my local NAPA and they set me up with a set of Kevlar reinforced belts. After a few hours of mowing I pulled the cover to re-tension and they no sign of abuse at all.

 

[RoyJackson]

When I pulled the cover off my Caroni, had something quite similar. The belts were destroyed and there were chunks, just like your picture, on 2 of the three pulleys

 

[dnw64]

OK I'll hope the new ones I put on hold up better.
Thanks

 

[m1garand762]

Loose belts create heat. Whenever you have multiple belts on the same pulley it is imperative that you get matched belts. A good belt shop will be able to get you belts from the same exact mold and stretch them to the exact length if there is any variation.

 

[Tinhack]

Wrong size belts or cheap belts. The belt(s) should NOT drop below the top of the pulley. They should also NOT touch the bottom of the pulley. This typically occurs when a mix of inch and metric sizes are used--Belts and pulleys. Usually from import products.

 

[dnw64]

I run a mid-size wood shop. 12 employees, $1mm+ in equipment. We used to ask for matched belts on our multi-belt equipment. Our supplier told us 15+ years ago that it is no longer a necessity, that all B43 belts are the same, etc.

HOWEVER, it was very clear, after installing the three new belts, that one was looser than the other. No idea as to the original ones. Never checked them, assuming the mfr knew what they were doing...

 

[nyone]

Did you check for straightness across both pulleys?
It could be a old bet got rusted in the pully and it's all over at that point.

I have had decent luck with chinese kevlar belts but I dont run 3 on the same pulleys.

 

[dnw64]

I didn't check for parallel on the sheaves. Will do that next time I check the belts.

Could have rusted, but it's not like it was sitting for years - just last fall to this spring - and I keep it under cover, so any moisture was just from environmental humidity.

 

[Michael In Tennessee]

Well, I guess I'm going to check my Caroni belts before next mow. I'll do that after I cuss the designer who put the roller grease zerks right behind the skids. I got to figure out how to grease the roller without unbolting the skids.