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General Information => Troubleshooting => Topic started by: mtnbob on June 09, 2008, 06:25:29 pm

Title: Help please. Alternator belt question
Post by: mtnbob on June 09, 2008, 06:25:29 pm
I just tore up my new alternator belt. I had replaced the bearing in my tensioner pulley in the last few days. The belt still looked fine when I did. It started slipping before it broke, but the tension on it looked good. Any suggestions before I put the new belt on? Is there something else I might look for that would have made the belt slip and break? Would too loose or to tight on belt tension have done this? My other belt that goes between the water pump and A/C is fine. I'm baffled. :shock:
Title: Help please. Alternator belt question
Post by: Dakotakid on June 09, 2008, 08:53:46 pm
I would first check that new bearing in the roller-skate tensioner wheel to ensure that you did not damage it when you pressed or banged the bearing into the pulley.

Just this past week, I had one of the air conditioner socket head type (cap screw is it??) bolts come loose and back out of it's threads and effectively destroy my new alternator belt. I am talking about the bolt on the belt side of the air conditioner, which ultimately acts as a pivot point for the air conditioner during belt tensioning adjustments. This bolt as a twin on the other side of the air conditioner housing. This is where the air conditioner is attached to it's steel mount which attaches to the front of the engine block.

When this bolt backed out, it contacted the external surface of the belt and "milled" the belt down. When I first saw the belt, I thought it had hydroplaned (been driving in lots of rain lately) and then twisted in it's groove. Took me a second to finger it out. The pivot bolt was gone.
I always carry at least two of the alternator belts with me in the trunk. Just in case irritating crap like this happens.
Title: Help please. Alternator belt question
Post by: mtnbob on June 09, 2008, 10:09:45 pm
The tensioner pulley seems smooth, I will look at the other bolts tomorrow my belt looked burned and twisted but I need to look at it in the light.
Title: Help please. Alternator belt question
Post by: Dakotakid on June 09, 2008, 11:19:50 pm
Low quality belt? Too narrow for the pulley grooves? I think Conti-tech (Continental) belts are absolutely great. I have never had a bad experience with them. Usually through Arizonaautohaus. Or Partsbin.com
Alternator bearings all right??????
Do all three pulleys line up good?
Too loose would indeed slip. No squealing prior to the break?
I usually go through 2 or even 3 of the alternator belts for every one water pump belt.
I'm flush out of scenerios.
Next!!!!!!
Title: Help please. Alternator belt question
Post by: Op-Ivy on June 10, 2008, 12:01:54 am
How did the belt break? Did it snap, split, tear? Picture?

I know the timing belt tensioner on my car was wobbling slightly causing the belt to ride up on it a bit. It started to fray and chip the side of the belt.
Title: Help please. Alternator belt question
Post by: mtnbob on June 10, 2008, 04:54:54 am
I will try to provide better details with a pic or two tonight. I'm teaching a juvenile offender program this week and might have time tonight to dig deeper. Thank you for the excellent suggestions so far. Why does it have to be the inside belt :shock: ??
Title: Help please. Alternator belt question
Post by: zukgod1 on June 10, 2008, 09:28:43 am
Quote from: "mtnbob"
Why does it have to be the inside belt :shock: ??


I'll second that notion!!

I ended up going with a shorter belt as I couldn't get the alt belt tight enough when the A/C was where it was suppose to be..
What a pain in the ass I say..
Title: Help please. Alternator belt question
Post by: dieselwagen on June 11, 2008, 01:13:01 pm
I ended up going with a shorter belt as I couldn't get the alt belt tight enough when the A/C was where it was suppose to be..
What a pain in the ass I say..[/quote]

used to have belt squeal, then went to shorter belt.
it also pulls the tensioner pulley closer to
center in its adjustment slot
too tight alt. belt  could mess up IP ?
Title: Help please. Alternator belt question
Post by: The Mad Hatter on June 11, 2008, 05:35:38 pm
I don't want to hijack this thread, but i'm having a similar issue.  My belt broke recently, and the one the store gave me was WAY too long.  Not even close, so i got this belt, but it seems to be slipping.

(http://i155.photobucket.com/albums/s297/rapscallion_83/IMG00008.jpg)

Sorry the pic ain't great.  Am i missing a pulley?  I'm gonna try tightening the belt some more.  Thanks for any help![/img]
Title: Help please. Alternator belt question
Post by: jtanguay on June 11, 2008, 05:41:36 pm
wow thats totally different than mine.  i have a tensioner below the alt and in front of the a/c compressor.  only way of adjusting belt tension and it's right at its end!!!  man do these alternators suck some serious juice.. no wonder the 1.9's had crank issues.  at least the v-belts have some give, but they're still a pain in the ass when they don't have any grip!  my belt squeals at idle sometimes if i have my a/c on max.
Title: Help please. Alternator belt question
Post by: The Mad Hatter on June 11, 2008, 05:45:44 pm
Well i think i'm missing a pulley.  I noticed a slot in the front of the A/C bracket, just below the alternator.  Nothing is on it on my car (obviously).
Title: Help please. Alternator belt question
Post by: mtnbob on June 11, 2008, 06:53:44 pm
Yes, definitely missing a tensioner pulley.

Ok here are pics from my car showing pulleys from top and side. Also pics of the belt close up on both sides. The belt is hard where it broke. Almost like it was cooked. The A/C is working fine still and the bottom belt seems great. The alternator pulley seems to spin without any noise or binding, and I just replaced the tensioner pulley bearing after it started squealing from time to time, but before it broke. The belt was a low quality one, from what I can tell. The new one is a Dayco, which is the best I can get locally. http://www.flickr.com/photos/11904434@N05/sets/72157601610859415/
Title: Help please. Alternator belt question
Post by: Dakotakid on June 11, 2008, 09:11:48 pm
Do they call it Dayco Top Cog? Those are pretty good belts. If you've checked everything else, put 'er on and go. It will stretch some after couple hundred miles.
Tensioning them is subjective in nature. Belts tend to shorten when they get to operating temp. Seriously. That might be the only thing on the planet that does!
Maybe the original was so loose it wadded up against the compressor pulley and then burned through in short order.
I say, don't loose any more sleep. Replace and goooooo!

Mad Hatter, someone "customized" your set-up and threw away the tensioner puller and hardware. That upper bracket has been...ahhh...modified. Stock upper bracket on these is a static piece, not an adjustable mechanism. The bearing on the original tensioner must have worn out and they got angry. Wow, don't even think about buying one of these pulleys from the dealer. Unless your name is Bill Gates. I made the mistake of ordering one abut 6 years ago (just for the pulley and bearing) and they jabbed me for $75.
Title: Help please. Alternator belt question
Post by: mtnbob on June 11, 2008, 10:20:56 pm
yes it is a Dayco Top Cog belt
Title: Help please. Alternator belt question
Post by: The Mad Hatter on June 12, 2008, 03:48:39 pm
Oh great.  Guess i'll just have to try and tighten the alternator up as best i can, and cross my fingers for now.
Title: check this out
Post by: theman53 on June 12, 2008, 07:57:14 pm
like I said check this out.

http://www.vwdieselparts.com/forum/viewtopic.php?t=8173

I have made my own a little differently, but not in full use yet as my alt is needing help.
When the bearing went out of the back of my alt. it would sometimes squel, even at ldle, sometimes it won't. And you really have to torque on the pulley to get it to move up/down...all with the belt off. It got so bad before I figured it out that the fans on the alt. would stop the alt from spinning and it burnt a spot in my belt and it shreded/snapped. I had tightend it like crazy before trying to get the noises to stop no luck. I thought it sounds really familiar to yours, but it could be way off. I would yank that guy off there and have it rebuilt, just in case. :D

PS...you'll see my post under yours about my current alt. delema :evil: