1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

my FB is eating alternator belts!!

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Old 08-10-04 | 10:50 PM
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Exclamation my FB is eating alternator belts!!

Hey...can someone help me out here?

My FB has been acting weird lately....a few weeks ago, the engine temp started to rise pretty high (to the second highest mark), then I smelled something burning for a second, then the alternator belt snapped (cuz all the dash lights lit up). This was in spite of me inspecting the belts just a few days beforehand, and none of them had any cracks or anything. It was in good shape.

So I had the belt replaced, and I really haven't driven the car for more than 50 - 100 miles over the past 2 weeks. I did notice that all throughout last week, however, when I started the car, it made this weird screaming noise that I often hear on some really old cars (like my FB hehe), and the noise was usually confined to startup. I didn't know what it was, and since the noise would disappear afterwards, I ignored it.

Then this week, I drove it for another 50 - 75 miles or so, and go figure, on Monday morning, while I was driving the car in the morning, about 5 min into the drive, the temps shot up again, I smelled something burn for a sec, and the dash lights came up....the belt snapped, AGAIN. A brand new belt at that.

Now I've been having problems w/ my FB running hot, and I had changed the radiator, I put a hi-flow cat on, the DP is not clogged, and I just had the t-stat, waterpump and fan replaced. I dunno why the temps shot up like that...but my guess is there's something wrong w/ the alternator, making it put out a lot more heat to the point it's breaking the belt? And would this heat reflect in my engine temps?

Any suggesstions/advice would be great. As of now, I'm thinking of taking the car to get the alternator checked out (if you have any suggesstions of shops to do this in the NoVa area, plz lemme know. RP doesn't do it...)

Thanks
~Ramy

EDIT: Oh yea, if it makes any difference, my FB is a 1984 GSL, 12A, 1.1L Carb.

Last edited by FDNewbie; 08-10-04 at 10:53 PM.
Old 08-11-04 | 12:08 AM
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faye x7's Avatar
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That screaming is the belt slipping probably, maybe your water pump is shot too if. Or maybe you don't have the belts tight enough.
Old 08-11-04 | 12:12 AM
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Sorry to hear about the troubles Ramy, I know how that feels. First off you can check the alternater yourself in your own driveway. Start the car up and while she is idling pull the positive terminal off the battery. If the car dies then the alternator is indeed bad and will need replaced, If the car continues to run for a few minutes then you can elemenate a bad alternator. BUT, it sounds to me that the bushings in the alternator might be going bad which is putting strain/resitence on the belt which will burn up the belt and eventually break it. One question for you, I assume you replaced the belt yourself. How tight did you make it? You do want to have a little play in the belt not extremely tight. Also do any of the other gauges do anything funny? You mentioned the temp gauge a few times. I feel that the car wasnt really over heating but the gauge was acting up due to fality voltage going through. Just my 2 cents. Let us know what happens.
Old 08-11-04 | 01:33 AM
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With the belt off, try manually turning the alternator... Feel ANY resistance? Same with the water pump. They should both turn fairly easily by hand, and should feel smooth... Also check the pullies... Rust or a rough spot willl sand right through a belt.
Old 08-11-04 | 03:25 AM
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You can allso try looking at how well your pulleys are aligned.

I had the same problem.My belts kept on breaking.I checked how well the pulleys line up with a steel ruler.It solved my problem,as mine was out a small amount.

Karis
Old 08-11-04 | 09:30 AM
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Originally Posted by r0taryluv
First off you can check the alternater yourself in your own driveway. Start the car up and while she is idling pull the positive terminal off the battery. If the car dies then the alternator is indeed bad and will need replaced, If the car continues to run for a few minutes then you can elemenate a bad alternator..

Not a good way to test a good alternator. Think about it.....


J.
Old 08-11-04 | 10:32 AM
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These cars eat cheap belts.

$3 belts are worth exactly what you pay for them. If you're getting someone to change the belt for you (man, my sister changes her own belts on her Honda!) then make sure they use high quality belts. Gates is a good brand.
Old 08-11-04 | 01:17 PM
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Aren't Napa belts made by Gates?
Old 08-11-04 | 09:05 PM
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Thanks for all the comments and advice guys. Actually, I hadn't replaced the belt myself, since the first time this happened it was really late at night, and I had crazy hours of work all week long, so I just dropped off the car at RP that same night (at like 3:30 am lol) so they had replaced it. On that note, I'd imagine they didn't use some el-cheapo belt, considering they charged me much more than $3 for it.

The other gauges seem to work just fine. Unfortunately, I believe the car does actually run hot when the temp gauge shoots up, because on occassion, I've seen smoke (it looked like it was coming from around the exhaust housing, where the dp begins, coming off the engine). Also, when she runs hot, sometimes I can sense or smell the heat. I usually just turn the heater on, fans on max, in the vent position, and in a few min the temps drop back down.

I just had the waterpump & fan replaced, and she's still running warm (fan was replaced because it had too much play...now I have an electric fan that's pretty much wired to run all the time hehe...lets see if that helps w/ temps!)

Why isn't pulling the + terminal off of the battery a good idea in testing the alternator?
Old 08-11-04 | 09:54 PM
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Originally Posted by FDNewbie
Why isn't pulling the + terminal off of the battery a good idea in testing the alternator?
1. It puts your hands in a situations where you're likely to act as a conductor. Its like sticking metal into an outlet.

2. AutoZone, Advanced, and some NAPA's will test your electrical system for free. FREE. No reason to waste time with these kinds of tests when you can use farily accurate test gear.
Old 08-11-04 | 10:01 PM
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Originally Posted by nevarmore
2. AutoZone, Advanced, and some NAPA's will test your electrical system for free. FREE. No reason to waste time with these kinds of tests when you can use farily accurate test gear.
Word? Guess where I'm going tomarrow! hehe
Old 08-11-04 | 10:42 PM
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Originally Posted by FDNewbie
Why isn't pulling the + terminal off of the battery a good idea in testing the alternator?

The posibility of frying the diodes in a good alternator...... Take it off the car and have it professionally tested.



John
Old 08-11-04 | 10:54 PM
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Having a parts store test the alternator isn't going to tell you whether or not you have worn out bushings. They can test your alternator and tell you it's "bad", which could be bs. Pull it out and bring it to an Automotive Electrical Shop. They can put it on a bench, crank up the amps and test and listen for noises like it was second nature. I can't stress enough having them rebuild an alternator or starter than some 5 yr old in bangcock on an assembly line filling your local parts store shelves. Plus you know what your getting. But, thats just my opinion
Old 08-12-04 | 12:43 AM
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Originally Posted by GavinJuice
Having a parts store test the alternator isn't going to tell you whether or not you have worn out bushings. They can test your alternator and tell you it's "bad", which could be bs. Pull it out and bring it to an Automotive Electrical Shop. They can put it on a bench, crank up the amps and test and listen for noises like it was second nature. I can't stress enough having them rebuild an alternator or starter than some 5 yr old in bangcock on an assembly line filling your local parts store shelves. Plus you know what your getting. But, thats just my opinion
I agree with you even though its against what I do and the advice I usually give. If you have a top notch car or are running a lot of electrical devices off of a good alternator, listen to GavinJuice. Treat your top shelf parts like top shelf parts.

In my experience with mostly stock vehicles, alternators, batteries, and starters are cheap and almost expected to fail right out of the box. So often that parts stores will very rarely give you any hassle if you return one. Thus when diagnosing electrical problems (which I HATE to do) I tend to roll with the test the parts monkey performs and replace parts that test bad. Parts stores do exist to sell parts, but for minor problems they have the test gear to give you a slightly biased second opinion.

Also, if the alternator is having problems, the battery probably is too. If one goes out on you you probably will be replacing the other very soon.
Old 08-12-04 | 02:54 AM
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100 bucks says it's bad alternator bearing.
Old 08-12-04 | 03:12 AM
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man for some reason at about 4 grand my alternator belt slips in ever gear.. makes me so mad. i hate hearing that thing squeel. im running a yoohoo belt so what is wrong. its tight and everything.???
Old 08-12-04 | 12:24 PM
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Originally Posted by bouis
These cars eat cheap belts.

$3 belts are worth exactly what you pay for them. If you're getting someone to change the belt for you (man, my sister changes her own belts on her Honda!) then make sure they use high quality belts. Gates is a good brand.



I'll add that you need to keep the belt tighter than you would on a piston engine.
Also, when checking alt bearings for excessive play, make sure that there is no fore and aft movement as well as side-to-side play. And check for a burr on the pulleys too, as that will eat up belts.
Old 08-12-04 | 06:21 PM
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I stopped by an automotive electical shop today that was recommended to me by RP...the shop has dozens of alternators and starters laying around on their shelves, so I'd say at least from the look of it, they seem to know what they're doing.

The guy checked the voltage the alternator was putting out, and it was fine (13.4 volts I believe). He listened to it, and told me if any bearings were bad, you would hear them...but my alternator is super quiet, so it's definitely not a bearing. He did try pulling on the belt, and he told me that he could almost turn the pulley, which means the belt is a little loose. He said that new belts for these older cars aren't self adjusting, so you have to retighten them after 3 days or so. He tightened the belt, and told me I'm good to go (w/o charging me for anything, at that).

Also, he said the screaming I got upon startup and when getting on the throttle hard was cuz the belt wasn't tight enough, so it was slipping... Hopefully the problem's fixed. We'll see in a few days...

The prob that remains tho is the engine runs hot...but that's another thread.
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