Burned up about burnt up PTO belts!

Jinzo Ningen

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OK. Quick question...

Recently bought a beautiful new (to me) mower and in its first 2 mowings I've smoked 2 sets of PTO belts. Everything on this mower has just been serviced - by me. All fluids, filters, grease fittings plus a fresh set of factory blades... so the culprit isn't any of these usual suspects. Also, all other belts in primo shape.

My thought is that the tensioner pulley on these belts is too loose, allowing the belts to slip - especially in thicker grass - to the point where the belts eventually become stretched, floppy and soon burn up. This seems like a common sense rationalization to me but I am unsure; you mower gurus and commercial guys might have a brighter light bulb than mine. :laughing: Does my diagnosis & solution sound right... or am I way off on this? I would like to try tightening the tension a couple of turns on the adjustment bolt, but if you guys think that doing this will have no effect (or worse, the opposite of what I hope to achieve), and if y'all think that it's probably something else then I want to hear from you ...before I go and fry another set o' belts. :confused2:

Thanks in advance!!!

- Jinzo
 

Scrubcadet10

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Are you using factory OEM belts or $10 knock offs from ebay or amazon?
i would check for excess play in pulleys, and make sure the spindles spin free with little effort too. and with the mower turned off engage the blade (If possible) and see if they might be rubbing on something.
 

Jinzo Ningen

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Free play in ALL pulleys and blades, etc. Belts that I purchased to replace were Stens brand, not OEM. Not sure what kind the PO used on it. The belts that shredded were black, not gray like GH belts, so they were likely cheap-o's, too.

I think I will try tightening the PTO's tension pulley. If that doesn't help then I guess I'll pony up for high dollar GH belts (3x as much!) to see if that will help any. :confused2:
 

Scrubcadet10

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Stems is OK, I used one on the cub cadet and it lasted probably 4 mowings and it just stretched, New oem belt and lasted all season.
I would try adjusting the tension first.
 

Jinzo Ningen

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Amazing what OEM will do for performance. Haven't have any issues since forgoing aftermarket and buying GH belts. When these finally do die I will replace with GH brand again - and pick up a new PTO Pulley Tensioner Spring, too... just to be on the safe side. They do stretch over time and it's only $3, so why not?:thumbsup:
 

Scrubcadet10

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:thumbsup:
Great news!
 

bertsmobile1

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Amazing what OEM will do for performance. Haven't have any issues since forgoing aftermarket and buying GH belts. When these finally do die I will replace with GH brand again - and pick up a new PTO Pulley Tensioner Spring, too... just to be on the safe side. They do stretch over time and it's only $3, so why not?:thumbsup:

Kevlar mower belts do not stretch much.
A 1/2" over a 100" belt would be near the maximum you can expect.
They wear thin on the sides then sit deeper into the V groove so become loose.
Like most companies, Stens do two lines of belts.
One is an identical belt to the original one, most come from the same factory as the original belt with a different colour wrapping.
They also do a standard series of M, A & B section belts, also in kevlar and covered with a blue wrap
Prime line sell the same belts branded as Pix also covered with blue wrap & they are all made in Mexico.
Down side of after market belts is the wholesaler buys them in a bundle , usually 100 and then the wholesaler puts them into the sleeves so it is not unheard of to get the right sleeve with the wrong belt in it.
Some times they come unmarked & the wholesaler brands the belts as well & again belts marked wrong are no unheard of.
Then you get the "fits" belts.
These are the standard size belt closest to the original sized belt
So you get things like Cub who use 21/32" section belts that are 1/32" wider than a std 5/8" belt so you get sold one that is a little shorter to make up for the fact it sits a little deeper in the V of the pulley.
Over time pulleys wear step into the V where the belt runs so if you have been running genuine 21/32" belts for hundreds of hours the try to fit a std 5/8 section belt, it will fall apart in no time flat.
 
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