: WTF Belt tensionner squeel?!?



JSMeloche
06-20-05, 12:53 PM
Ever since I got a new alternator the acc. belt squeels! So I got it back to the dealer, they told me its the Belt tensioner pully gone bad, they assured me its not my rebuild alt doing this.
Fine, go to the part store, get a new pully and change it (25$ instead of 60$ @ dealer + labor). STILL squeeling. Back to the dealer, Idler pully is bad. Hummm k, changed the idler pully myself (same price). STILL SQUEELING :banghead:. So I brought it to a small garage near my work to get a second opinion. They are telling me its the belt tensioner that is squeeling, not the pully but the tensionner itself?!?

I find this odd a bit, the squeeling starts at around 2500-3000rpm, lower if engine is cold, and keeps getting louder as rpm go up. So its a squeeling, like a bearing gone bad, I dont understand how a tensioner, that is basicaly a spring, can squeel like a worn out bearing?!?

Ive exercised the tensioner at least 4 times doing the idler and tensioner pully, it seems rather smooth, a bit stiff but smooth.

I found a new tensioner on ebay for a very decent price (19.99$!!!) so I will replace it but I would like to understand how a freakin spring can squeel like a bearing?!?

Ranger
06-20-05, 03:19 PM
That does not make sense. Are any of the pullies out of line by any chance? Was the P/S pully removed to get at anything. I recall Bbob once saying that there is a small lug on the pump I think it was that had to fit into a small notch. If it wasn't, it would not run true and may squeel. I also recall someone else having this problem once and replacing the belt solved it, though I must admit that doesn't make much sense to me. It would on the old "V" belts but not on the serp's.

JSMeloche
06-20-05, 03:44 PM
Nobody touched the PS pully. A/C Compressor was replaced last year, and I installed a new belt. Alternator is rebuilt, been in car for 4 weeks and it squeeled even since. The GM tech putted some belt "dressing", noise went away for a day, next morning its back... Belt tensioner pully is new, idler pully is new, alternator is new.... N e way, ill try the belt tensioner, its the last "cheap" way, after that GM is gonna get a load of crap ;)

eldorado1
06-20-05, 03:56 PM
Alternator isn't fully seated or perhaps they installed the wrong pulley (either wrong rib count, or different offset, etc). I bet if you look down at the alternator, one end of the belt is lifted up a bit, or else looks misaligned.

lry99eldo
06-20-05, 04:22 PM
Hi JSM, Hmmmmm. Don't replace the idler assy. or idler wheel/bearing just yet. Slip a breaker bar into the idler off tension access and loosen the belt but don't take it off. If you have to, have some one hold the tensioner off as you go through all the pullies individually. Start with that new alternator, it should spin free. If it has any resistance take it back to the dealer. It's quite possible that the concentricity of the armature shaft and the alternator halves is not in line and in fact may even get worse as it runs up to speed.
The idler wheel it's self should be a replaceable unit, just remember that the shoulder bolt that is the bearing shaft is probably LEFT HAND thread. If you put a socket on that bolt and go to loosen it as a right hand thread and it puts pressure on the belt then it's most likely left hand thread.
The tensioner assy it's self shouldn't be bad but they are a spring unit but that's a long shot. As they get older you'll see that at idle that tensioner will appear to be bouncing causing a chatter but not a squeal.
I'm only saying this because the belt dressing spray was used and the squeal went away for a day right after the insallation of the new alternator right?. You've got to remember that the idler is just that and the only thing it does is apply outward pressure and from the SMOOTH side of the belt so what does that tell you? Idler bearings themselves go bad but you'll be able to SEE that and or be able to wobble it by hand with the belt tension engaged.
Sounds like your "stealer" just wants you to go away. Which if it is the case come prepared with a sign to put in your rear window telling the World what you think of that dealer. Works every time!!!
lry99eldo

JSMeloche
06-20-05, 07:27 PM
Hi JSM, Hmmmmm. Don't replace the idler assy. or idler wheel/bearing just yet. Slip a breaker bar into the idler off tension access and loosen the belt but don't take it off. If you have to, have some one hold the tensioner off as you go through all the pullies individually. Start with that new alternator, it should spin free. If it has any resistance take it back to the dealer. It's quite possible that the concentricity of the armature shaft and the alternator halves is not in line and in fact may even get worse as it runs up to speed.
The idler wheel it's self should be a replaceable unit, just remember that the shoulder bolt that is the bearing shaft is probably LEFT HAND thread. If you put a socket on that bolt and go to loosen it as a right hand thread and it puts pressure on the belt then it's most likely left hand thread.
The tensioner assy it's self shouldn't be bad but they are a spring unit but that's a long shot. As they get older you'll see that at idle that tensioner will appear to be bouncing causing a chatter but not a squeal.
I'm only saying this because the belt dressing spray was used and the squeal went away for a day right after the insallation of the new alternator right?. You've got to remember that the idler is just that and the only thing it does is apply outward pressure and from the SMOOTH side of the belt so what does that tell you? Idler bearings themselves go bad but you'll be able to SEE that and or be able to wobble it by hand with the belt tension engaged.
Sounds like your "stealer" just wants you to go away. Which if it is the case come prepared with a sign to put in your rear window telling the World what you think of that dealer. Works every time!!!
lry99eldo

Idler pully has been replaced yesterday, the old one ran pretty smoothly but had some lateral play in it. It has been replace with a brand new metal unit. Same thing goes for the Tensionner pully.
Last week the Dealer told me there was some play in the tensioner assembly and this could be causing the problems. And that it squeeked when manualy operated. I ignored them, this sounded too stupid lol.
Now this morning I brought the car to another garage (independant) and them too told me its the tensioner assembly. They told me the tech put a stethoscope directly on the tensioner and almost rip his ear off from the screeching noise. N e way, the tensioner is already purchased, I will get it in 4-10 days, I will keep you updated on how this work.
I might have trouble getting the dealer to replace the alternator for free. The alternator was purchased by me at a local part store. Part store cost: 250$, dealer cost 450$. But I dont trust the part store install shop.
The part store will honor the return policy if I bring them the part removed, but the dealer probably wont want to R&R an alternator they are not responsible of for free.

Ranger
06-20-05, 10:14 PM
I was going to suggest a stethescope. I recently sweet talked the girls at medical to get me one when I had my physical at work. I modified it for automotive use and it is amazing what you can hear with these things. From what the mechanic told you when he used it I'd say you have it nailed down.

eldorado1
06-20-05, 11:02 PM
I was going to suggest a stethescope.

A long screwdriver or simple 3/8" hose works just as well.....

davesdeville
06-21-05, 08:44 PM
I wouldn't say "just as well" because in my experiance especially the screwdriver doesn't. But they do work also.

cl1986
06-21-05, 11:53 PM
I washed my motor and got degreaser on the belt and it squealed and sqauked for a month, now its fine.

Could be the new belt and/or new alt pully combo, it will probrably go away, not much u can do about it.

JSMeloche
07-04-05, 09:09 AM
New belt tensioner is in, it is a lot smoother then the old one (with the breaker bar). But the freakin squeek is still there... its less noticeable but still there!!! I tried gently loosening the belt while the engine is running and get very loud chirp coming from the power steering area... Im really starting to think its the belt squeeling on the PS pully. The PS pully has a small wobble, about 1 mm is this normal? Maybee the PS is going away.
Advice any one???

So if any one needs a good used belt tensioner, mine is for sale. Bearing is brand new 2 weeks old.

Spyder
07-04-05, 10:59 AM
The GM tech should have never used belt dressing on it either...that is just a band aid. Replace the belt! Have you done that yet, or did I miss it in your posts? If you want to try saving a couple of bucks, take the belt off, wash the hell out of it with soapy water, but make sure you rinse it completely and get everything off of it...and try putting it back on. The belt dressing likely made it worse, as it'll get rid of a squeal for a day or two, like you said, then it'll come back with a vengeance.

JSMeloche
07-04-05, 02:59 PM
The belt is one year old, I will try this this weekend, I have some free time and a garage full of tool hehe. I should have tried it first.... now I bought: One idler pully (30$), one tensionner pully (30$), one tensioner with a new pully (20$+20$ shipping), 15$ diagnostic at GY garage, 35$ diagnostic at GM dealer. AND ITS STILL SQUEALING. and now i have a spare tensioner...

BeelzeBob
07-04-05, 04:10 PM
Did you check that the power steering pump pulley is in alignment..???

Look at the mount that the power steering pump sits in. It has a lug machined in it that overhangs the front face of the block. The lug is precision machined to sit flush against the front face of the block for proper alignment. If you look carefully at the power steering mounting bracket you can easily see the lug hanging down in front of the block front face. There should be no clearance between the lug and the block. If there is, loosen the belt and slip it off the power steering pulley. Loosen the one bolt holding the power steering pump to the block (it is on the right side (rear) of the bracket down between the bracket and the cam cover. Slide the power steering pump rearward as far as possible on the block (push toward the drivers side of the car...i.e...rearward on the engine) so as to seat the lug firmly against the block front face and tighten the mounting bolt. Reinstall the belt.


Also, double check for proper belt engagement on all the pulleys. I have investigated "incurable" belt squeels more than once to find a pulley with the belt one rib off so that the belt is being forced to one side and then the other....it doesn't like that and will squeel in protest.

I know you guys know I like the OEM parts....but....get the OEM idler pulley. Many times the aftermarket generic pulleys do not have the same crown or geometry on the face of the pulleys to ensure proper belt tracking. It is very easy to get a consistent or intermitant squeel out of the BACKSIDE of the belt as it tries to track crookedly on a flat pulley. The belt will look straight but in the mean time the pulley will be trying to make it track out of line due to the geometry of the pulley face causing the squeel.

cl1986
07-04-05, 06:34 PM
How long has it been squealing?? 2 months?? Thats what mine took to quiet down after the degreaser. Now it makes no noise at all, but a new belt in the trunk aint a bad idea either, remember to buy an extra 1/2" drive rachet or breaker bar to go with it.

JSMeloche
07-04-05, 07:51 PM
The GM tech should have never used belt dressing on it either...that is just a band aid. Replace the belt! Have you done that yet, or did I miss it in your posts? If you want to try saving a couple of bucks, take the belt off, wash the hell out of it with soapy water, but make sure you rinse it completely and get everything off of it...and try putting it back on. The belt dressing likely made it worse, as it'll get rid of a squeal for a day or two, like you said, then it'll come back with a vengeance.

Today the squeel is almost inexistant, non hearable from the inside but still noticeable with the windows down.

But the winner to solving my problem is SPYDER!!!
It seems to be fixed but I will wait a few days (like the belt dressing) before calling it complete success :D
I didnt even remove the belt. I took a small soft bristle brush and some hot soapy (M. Clean) water and went to my car. I turned the car on and while the engine was running I brushed the top of the belt, the bottom and the PS pully. Now there is no squeeling watsoever even after the water dried out.
While the hood was open and i had a brush and a bucket in my hand I cleaned all the underhood :thumbsup:

Thanks Bbob for the advice, I will look into it this weekend just to make sure. I made sure that all the pully were engaged yesterday when i installed the new tensioner. The battery was removed so I could see farely well. The PS pully is wobling from side to side but its almost unoticeable, not even 1mm, just noticeable... I just find it weird that this has all started with a new alternator...
And the original plastic pullies both had some noticeable lateral wobble (100k miles)

All this reminds me of what a teacher told me when I first started programming (Im a Programmer/Analyst) : KISS; Keep It Simple STUPID!!!

Moral of the story, I changed 100$ of parts to found out a bucket of soapy water did the trick....

I hope this is completely fixed now ;)

JSMeloche
07-06-05, 10:13 AM
Problem isnt completely solved... it was still squeeking this morning, but a loooooot less, I will try to clean it again

Spyder
07-06-05, 11:09 AM
just take the thing off...scrub the hell out of all the pulleys and everything that contacts the belt, as well as the belt...hopefully that is all it is, once you get that belt dressing off...