belts keep shredding

I am willing to bet the belt lost proper tension. If they any bit loose they go quick. I ditched the lock nut (should be replaced everytime it is removed) on mine and went to a standard nut with a lock washer and I don't have issues loosing tension.

 

Out of curiosity - have there been aftermarket belts that retain tension and/or last longer than the OEM?

I saw something on carbon fiber and/or kevlar belts - are they out there? Do they work?

 

most of the accessories belts are fractional hp metric sized industrial belts, they don't take kindly to improper tension or misalignment. the other thing to look for is the finish on the pulley sheave, over time some start to peel & flake and the sharp edges will shred belts.

 

These are symptoms of an accessory with a bearing freezing up.

Remove the belt(s) and spin the accessories by hand, you will find a rough running bearing, something with a grinding feel, they should spin freely by hand smooth with no or little drag or noise. Heat plays a factor and could induce the failure, when things seem fine when cold.

Something is binding freezing or dragging causing a large amount of friction on the belt (ever have a ac compressor or alternator bearing fail) it smokes the belt rapidly.

Makes sense no?

 

I had exactly the same issue. The car ran properly, except it would sometimes make a belt-squealing sound. I checked/adjusted the tension (the correct spec is tighter than you might think). Good for a little bit, then started squealing again. I changed the alternator and water pump belts. Same thing happened. Next I had my water pump rebuilt. Same thing. Then I noticed shredded belt particals gathering down low in the engine bay, close to the alternator. Around the same time I discovered that my headlights got really bright while the squealing sound occurred. I hadn't noticed this until I was on a night time drive. I had the alternator rebuilt, and everything has been fine ever since. I think the regulator was failing, which caused too much alternator output at times. When this happened, the alternator got harder to turn than it should be, causing the belt slippage/shredding.

 

If you have an idler pulley, check that for rough edges. A friend had this same problem, and after checking everything as suggested above, found the idler had some edges - replaced the pulley and no more issues.

 

Only way you are getting "squealing" is if either the belt is slipping or a bearing is failing

 

I need a workout regimen!

 

I had the same problem. Root cause was the alternator. Got it rebuilt and i have gone 6000 miles so far without issues.

 

When my belt was slipping it actually left this "remnant" on the alternator pully. I was very confused at first, as this really looked like an actual belt that fit perfectly on the pully... no seams or anything. I think there is a high plastic content in these belts, and when they get hot enough they will actually melt and reform into a different shape.
Image Unavailable, Please Login

 

Which belt? My water pump belt (polyflex) likes to be very tight. They're thin but very strong belts. If there's any looseness at all, they'll burn up. The alternator belt doesn't need to be as tight, but is still kept pretty snug. I use a good (padded) ratchet as a lever on the water pump tensioner when tightening. Same with the alternator. In over a year, I've only lost one WP belt and that was due to looseness. As expected, there was some erratic movement in the water temp gauge before it went.

 

check the profile of these belts. sometimes an aftermarket belt has a deeper or shallower v.
this will affect how the belt rides in the pulley creating heat and premature failure.

 

I have posted frequently about this problem. Many single belt cars did this. Ferrari made an update 2 belt kit to solve it back in the early 80s. I sourced one many years ago and fixed mine. I shredded about 4 belts early on. Not anymore.

 

I have posted frequently about this problem. Many single belt cars did this. Ferrari made an update 2 belt kit to solve it back in the early 80s. I sourced one many years ago and fixed mine. I shredded about 4 belts early on. Not anymore.

 

I too experienced this with my 83 Euro qv. It keept melting down my new belts. As mentioned above, I was not getting enough tension on the belt. If you ever hear a squeel, you need more tension! You should only be able to deflect (bend in or out) the belt between pulleys very little, I believe it was under a quarter of an inch IIRC. There is also a belt tension tool to measure deflection which would take the quess work out of it. Dealer or manual has the spec. I never used the tool, but after I got the belt tight enough to the correct tension, It never happened again.

 

It might make sense to install the new belt do a couple easy miles, then retension again-after the belt stretches/wears in.

 

I agree that this may simply be a case of an improperly tensioned belt, but I would take a really good look at the water pump and the alternator...

 

Yeah, that was my car, as PAD knows, since he helped me work on it. The pulley on the alternator was chewed up, and it was shredding the belts. That pulley, at least on my 328, is a proprietary design for the Ferraris, to get the belt to line up with the damper. I bought a new one from Ricambi, made by Hill Engineering. It is a much better pulley than the original, very high quality fit and finish.

But there was a secondary problem that was contributing to this. When I bought the car, the AC unit had been removed. When they did that, they removed all of the studs. The alternator tensioner bracket mounts to the timing cover and it not directly bolted to the block. The timing cover was being held on by one bolt!! I went to the box of parts that came with the car, and I found the old studs, and ran a couple of them back into the block, and bolted down the timing cover so it no long could move and flex.

With the timing cover good and tight, and with the new pulley, the car now runs great!! I've even driven it from NJ to Watkins Glen, NY (about 250 mi. each way), and not a bit of trouble from the belt anymore.

 

p.s. The original alternator pulley is aluminum. It can get chewed up very easily, and once the surface is damaged, it will shred the belt. It cannot be repaired. Just buy a new one. Daniel at Ricambi keeps them in stock.

 

+1

I used to work on equipment (not cars) which used the same type of anodised aluminium pulley and the same Gates Polyflex belts. We were forever changing belts until we introduced a policy of inspecting the pulleys and if the anodized surface had been worn through we would replace it. End of belt problems.