Why Do My V-Belts Roll Over & Die?
OK, I have this Garden Way "Super Tomahawk" Chipper / Shredder, 8 HP Briggs & Stratton engine. Nice sturdy, well built machine, and it's only 22 years old. It does a great job of chewing up limbs, twigs, old mulch, whatever. But it will only run for about 3 hours before the belt rolls over on it's side and self destructs.
The belt is a 5L290, 29 inches long X about 5/8 wide. It is tensioned by an idler pressing in from the outside. The idler and both of the V pulleys are about 3-1/2" diameter.
All three pulleys are aligned properly, the idler spins freely, the belt is the correct size, and I have the idler tension set correctly according to the operator's manual.
This morning I bought a new belt that was supposed to be stouter than the 5L290, with more fabric in it. Same thing...3 hours or a bit less and I start smelling smoke and I look and the belt is running on it's side and coming apart
So what makes these belts roll over on their side?
why do my v-belts roll over and die?
John, if your machine is 22 tears old, perhaps the pulleys are worn so that the belts are bottoming out in the bottom of the pulley. Normally the belts should be above the bottom of the groove, this is what keeps the belts from rolling over. Hope this helps.
John, I make pulleys for a living, and I have never heard of such behavior.
Misalignments seem most likely, but as you have stated all pulleys are in alignment.
What I think is happening is that you have too much power and too much load for that size of belt and when put under stress they are being distroyed. I'd suggest adding another belt (or two) or replace the existing sheaves for use with heavier belts. The power transfer design on your chipper is just too lighweight for the application.
Last edited by Mike Burdick; 01-19-2008 at 10:25 PM.
Just as a point of reference: my Troy-Bilt 12 HP chipper uses one belt and hasn't had a belt problem in 7 years of residential use.
in Byng OK
in Byng OK
What Studentjim said..........
Since you said it's 22 years old, I trust you've had it most, if not all those years. Has it done this since new? or just the last few years.
I've seen worn pulleys raise hell with nice, new belts. If a belt rides against the bottom of a pulley, it'll roll, or even throw clear off. When the pulley is badly worn, and the belt rides on a shoulder in the groove, you are in for trouble. Even if it doesn't bottom. Seems like the more belt speed, the more critical it is.
My Plumber buddy's 4x4 Tcheeby would roll the alt belt at freeway speeds, but not in town. After a couple hours on the road, it'd throw clear off. Told him if he'd install me a new moen faucet in MaMa's kitchen sink, I'd fix his truck forever. Cost me 4 or 5 bucks for a new alt. pulley. Of course, his boss probably paid for the faucet, so I guess we got a good deal.....all except his boss!!!!
Did the tensioner end up on the wrong side of the belt at some point? Seems like it should probably be on the outside for best result.
We had a compressor doing this here offshore. We'd replaced the belts, and they flipped. The belts had been stored for some time, and had been twisted into 4 loops to mak ethem more compact. Vee belts should always be stored in odd numbers of loops (1, 3, 5 etc) or they will take on a permanent twist.
Next time you buy one, before opening it up, count the loops.
One more thing
Any chips that get into V can build up, or a single big one can be enough to flip a belt. Not likely here, but possible in some applications.