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BuildBreakRepeat

BuildBreakRepeat

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McKenzie Bridge, Oregon
Afternoon everyone. My tj has developed a problem recently where the belt will screech and scream extremely loud for the first 10 min after startup. I’ve read and researched everything about belt noise, and so replaced my tensioner pulley, belt, and idler pulley. The noise got a tiny bit better but only a little bit. I pretty much wake up the whole neighborhood when I start it up at 0500 for work :confused: Any help concerning what or how to check next would be very much appreciated!

A few key facts:

Noise goes away after driving for 10 min

It started a few months back while camping out in the snow (very cold temps)

It’s coming from the alternator side of the engine where the pulleys I already replaced are
 
Cornbread said:
Have you checked to see if any coolant is leaking somewhere? If coolant gets on a belt it will squeal.
Click to expand...

I did check all over for leaks, even cleaned the new belt with soapy water (online fix said it would work). I did read about the possible crank pulley being out of alignment over time and causing the belt to deflect and make noise. Been trying to fix this for months with no results. I could take a video and post a link to see if that help.
 
image.jpg
Any way of telling from this? I usually don’t rely on autozone to always get stuff right but I figured what could they mess up with a belt @Chris
 
BuildBreakRepeat said:
View attachment 74763Any way of telling from this? I usually don’t rely on autozone to always get stuff right but I figured what could they mess up with a belt @Chris
Click to expand...

That's the right one, 88.2" in length.

Now I'm stumped! Screeching is either going to be a bad belt or a bad pulley bearing though, no question about it.
 
Chris said:
That's the right one, 88.2" in length.

Now I'm stumped! Screeching is either going to be a bad belt or a bad pulley bearing though, no question about it.
Click to expand...
I do have slight ( and I mean extremely slight) play in the power steering pulley when I checked them all with the belt off. Possibly time for a new pump? Or upgraded pump? Or power assist? Or full hydr......oh shoot here I go again down the rabbit hole of upgrades lol! Just playing...confusing because it’s coming from the side of the parts I replaced which should have made a difference. Weird. Is alternator a possibility? Or would the bearing sound from that not go away after some driving like mine does?
 
BuildBreakRepeat said:
I do have slight ( and I mean extremely slight) play in the power steering pulley when I checked them all with the belt off. Possibly time for a new pump? Or upgraded pump? Or power assist? Or full hydr......oh shoot here I go again down the rabbit hole of upgrades lol! Just playing...confusing because it’s coming from the side of the parts I replaced which should have made a difference. Weird. Is alternator a possibility? Or would the bearing sound from that not go away after some driving like mine does?
Click to expand...

I think you may have a pulley bearing going out but I can say this, sometimes when I let my GMC pickup sit outside over night on rainy or humid night, the next morning the belt will squeal for about 10 minutes. Almost seems as if the heat from the engine dries the moisture then the noise goes away. But this isn't really loud, its just an annoying squeak.
 
BuildBreakRepeat said:
I do have slight ( and I mean extremely slight) play in the power steering pulley when I checked them all with the belt off. Possibly time for a new pump? Or upgraded pump? Or power assist? Or full hydr......oh shoot here I go again down the rabbit hole of upgrades lol! Just playing...confusing because it’s coming from the side of the parts I replaced which should have made a difference. Weird. Is alternator a possibility? Or would the bearing sound from that not go away after some driving like mine does?
Click to expand...
Have you briefly started the engine with the belt off..?
Just to confirm whether it's the belt or not.
If it squeals with the belt off, then you know its something else.
 
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Cornbread said:
I think you may have a pulley bearing going out but I can say this, sometimes when I let my GMC pickup sit outside over night on rainy or humid night, the next morning the belt will squeal for about 10 minutes. Almost seems as if the heat from the engine dries the moisture then the noise goes away. But this isn't really loud, its just an annoying squeak.
Click to expand...

Honestly it could be the winter time water on the belt, it does have the characteristics of going away once the engine gets warm enough.
 
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KCsTJ said:
Have you briefly started the engine with the belt off..?
Just to confirm whether it's the belt or not.
If it squeals with the belt off, then you know its something else.
Click to expand...

Good point, I’ll try that today! When I listen to it closely it sounds like my alternator is screaming. When I asked around a few months ago another place told me the something about how temps affect the grease inside of the alternator or something along those lines....I’m not scared to replace the alternator just hoping that would actually fix it if I did lol
 
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BuildBreakRepeat said:
I do have slight ( and I mean extremely slight) play in the power steering pulley when I checked them all with the belt off. Possibly time for a new pump? Or upgraded pump? Or power assist? Or full hydr......oh shoot here I go again down the rabbit hole of upgrades lol! Just playing...confusing because it’s coming from the side of the parts I replaced which should have made a difference. Weird. Is alternator a possibility? Or would the bearing sound from that not go away after some driving like mine does?
Click to expand...

If it was a bad bearing, I could see it coming and going, butI don't think it would only happen on start-up.

The alternator pulley is indeed a big possibility. Any of those pulleys have bearings in them, so the trick is going to be figuring out which one.

I'd open the hood while it's making the noise and spray some sort of lubricant on the inside of the pulleys one-by-one until you get the sound to go away. That's always what I do in this sort of situation.
 
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Sounds like the bearings in the alternator since you say it is coming from the alternator side of the engine. A bad AC bearing will also act like that but usually turing the AC on or off will change the squeal and let you know that the AC pully bearing is the problem.

Take Chris's advice and spray some lubricant (WD-40 is what I use) behind the pully to help narrow down the culprit.
 
Normally the squeal can come from the belt not being tensioned properly...had to adjust the Alternator using the crowbar on the swing arm. (had to do this on a few older cars I've owned) The squeal would go after the car had warmed up.
 
Kiwi TJ said:
Normally the squeal can come from the belt not being tensioned properly...had to adjust the Alternator using the crowbar on the swing arm. (had to do this on a few older cars I've owned) The squeal would go after the car had warmed up.
Click to expand...
True, my 97 has to be tightened manually, no automatic tensioner.
The op should have an automatic tensioner which keeps constant tension on the belt.
Strange, a 10 minute squeal then it goes away, gotta be the belt somehow
 
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