Serpentine Belt Failure.

[George7941]

I recently had a serpentine belt break on one of our company trucks while on the road and I had to spend a friday evening going and changing it. The belt had about 100k km(62k mi) and was replaced about four years ago.

The reason I did not change it sooner is that I look around in the engine compartment of all our trucks every week to keep an eye out for potential problems. I assumed that the belt would give me enough warning before it failed.

Truck has been working well with the new belt for about a month now, so there is not anything else wrong with it, like a tensioner or water pump.

Has anyone else experienced this sudden failure of a serpentine belt with no warning signs like major cracking or chunking of the ribs?

 

[Saturn_Fan]

Originally Posted By: George7941
I recently had a serpentine belt break on one of our company trucks while on the road and I had to spend a friday evening going and changing it. The belt had about 100k km(62k mi) and was replaced about four years ago.

The reason I did not change it sooner is that I look around in the engine compartment of all our trucks every week to keep an eye out for potential problems. I assumed that the belt would give me enough warning before it failed.

Truck has been working well with the new belt for about a month now, so there is not anything else wrong with it, like a tensioner or water pump.

Has anyone else experienced this sudden failure of a serpentine belt with no warning signs like major cracking or chunking of the ribs?


That seems very unusual. There is usually some tell-tale signs like cracking, fraying, noise, etc. that is your signal. Dumb question, but are you sure the tensioner is okay?

I know a guy who carries a spare serpentine belt and the wrench needed in his trunk because a belt stranded him one time. Maybe this isn't such a bad practice as I would not want this happening in -30F wind chill conditions on a lonely two lane road in the dark.

I have had serpentine belts on mine and family member's vehicles go as far as 100,000 miles but had one go on my mom's 03 Sentra at 32,000 miles recently. She had plenty of warning though as it was really loud and showed cracking.

 

[Chris142]

My boss had a relativly new Gates Serp belt break. He was parking in a parking lot and lost ps suddenly.

 

[JHZR2]

wow, I didnt realize this happened much at all...

I was always under the impression that they give lots of warning.

Maybe bad batches though???

 

[Saturn_Fan]

Originally Posted By: Chris142
My boss had a relativly new Gates Serp belt break. He was parking in a parking lot and lost ps suddenly.


If I had that happen to me I'd save the belt/packaging and report it to Gates so they might be able to track down this problem on one of their production lines. I am sure there are numbers that tell them what shift, what line, what date the belt was produced.

 

[WishIhadatruck]

I always change mine every 5 years and have never had a problem. They are usually just starting to show some minor cracking at that point.

 

[cheetahdriver]

it's common. i used to be a Plant Engineering Manager with Dayco, and have done consulting work with Gates. serpentine belts will not give any particular warning signs before failure. the cracks you are used to with V belts are due to bending cycles on the depth of the rubber used to grab the pulley (actually it's a sheeve, but nobody calls it that anymore). since the poly-V belt (which is the technical name for the belt) doesn't have the depth of a single V belt, you don't get the cracking.

failure happens one of two ways.

1) delamination of the rubber from the cord line. this causes the belt OC distance to get longer and it will jump the pullys the next time around. i have seen this sort of failure cause catastrophic failure of the accessory system when the belt gets wrapped around the alternator and then rips it out of the mounts when the engine drive pulley takes up the slack.

2) failure of the cord. typically this only happens in the polyester belts. the kevlar belts almost always delaminate for obvious reasons. this is the "found it on the ground" failure.

poly-v belts are typically good for about 60k. there was some work on one that would last 100k plus, but it couldn't handle cold weather starts. my replacement rule is 50k or 5 years, and throw the old one in the trunk. if for some reason your current one does break, you will have a spare right there.

you do have a 3/8" ratchet handy, right??.....

the plant/date/shift numbers are on the belt, but it may or may not get to anyone who can tell what happened. i have seen cord changes that left a bare part of the sleeve, but looked good after it was cut.

 

[Saturn_Fan]

Originally Posted By: cheetahdriver
it's common. i used to be a Plant Engineering Manager with Dayco, and have done consulting work with Gates. serpentine belts will not give any particular warning signs before failure. the cracks you are used to with V belts are due to bending cycles on the depth of the rubber used to grab the pulley (actually it's a sheeve, but nobody calls it that anymore). since the poly-V belt (which is the technical name for the belt) doesn't have the depth of a single V belt, you don't get the cracking.

failure happens one of two ways.

1) delamination of the rubber from the cord line. this causes the belt OC distance to get longer and it will jump the pullys the next time around. i have seen this sort of failure cause catastrophic failure of the accessory system when the belt gets wrapped around the alternator and then rips it out of the mounts when the engine drive pulley takes up the slack.

2) failure of the cord. typically this only happens in the polyester belts. the kevlar belts almost always delaminate for obvious reasons. this is the "found it on the ground" failure.

poly-v belts are typically good for about 60k. there was some work on one that would last 100k plus, but it couldn't handle cold weather starts. my replacement rule is 50k or 5 years, and throw the old one in the trunk. if for some reason your current one does break, you will have a spare right there.

you do have a 3/8" ratchet handy, right??.....


Thanks for the very informative post cheetahd. I think I will start keeping my old belt and throw it in the trunk. My Saturn 1.9 serpentine replacement is literally an 8-10 minute task and involves tying a string on the end of the box wrench and tying it to the engine to act as a third hand as you slip on the new one. Looks funny while you're doing it, but it works.

If you had to recommend a serpentine belt brand/model, which one would it be?

 

[JHZR2]

yeah, that is a great post... thanks!!!

 

[JTK]

I've never seen a serp belt break or come off on it's own. The 'failure' was caused by some other failing rotating element (tensioner, idler, compressor, etc..) or due to oil or coolant leakage on to the belt.

Joel

 

[1sttruck]

'Belt conditioner' to quieten a squeaking belt is bad stuff as it swells and softens the elastomers, then it dries up to an even worse condition needing more conditioner, etc.

Spraying an engine down with engine cleaner might not be the best thing for a belt, even though they're usually designed to be somewhat 'oil proof'.

 

[Kestas]

The belt conditioners that I've seen said not to use it on multigrooved belts.

 

[mechtech2]

JTK beat me to it.
A very old used belt can fail, but I strongly suggest checking/replacing pulleys, tensioner, and maybe the AC , alt or PS.

 

[George7941]

Re warning thru noise from the belt, the belt will have to be really noisy to make itself heard above a truck diesel engine.

 

[TylerL]

Gates makes good oem stuff.
From google searches it seems Dayco belts aren't as good.

 

[Jim Spahr]

I have had an old style Vee belt break but never a serp. belt and I have had over 100 k miles on them. I don't advocate that however. I like the every 50 or 60 k miles routine.

 

[The_Jeff]

I personally love the gatorbacks, they're loud for a week but very sticky.

 

[pbm]

After reading this thread I just changed the original belt in my 02' Buick Century that has just under 100K (99400 mi). I am amazed that the original looks so good with no visible cracks. I replaced the original GM belt with an ACDelco. It took about 4 minutes to change. The Serpentine belt was a great invention IMO.

PS: I still have the original Delco battery too.

 

[Saturn_Fan]

pbm: I think you did yourself a great service by changing that one out with that many miles on it. I might look at changing out that original 6 yo battery as well and you'd be all set for winter.