Squeaky belt drive question

EJD

EJD

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Are there any components in the Belt Drive category that would cause the typical embarrassing squeaky belt noise only when its wet? I have a new belt, new tensioner pulley, and new idler pulley now and its still doing this but it seems only when its wet outside.

I know this sounds kinda dumb and to me does not make sense but let me explain the situation. I've recently replaced a tensioner pulley on my Jeep because of a chirping type noise, and it went away once I replaced that pulley. A few days later I hear a small chirping sound again, I figure it is probably the old idler pulley that I should have replaced at the same time but didn't so I replace that and the noise goes away.

Then the next day it rains, I start up the Jeep and something in the belt drive is chirping again just as it was before I replaced anything. It makes the noise for the next few days, all while its rainy or wet out. Today its dry, no rain or water anywhere, I start it up and no noise. WTF is going on here?

Does this make sense to anyone? Does it sound like I have a bad tensioner pulley? I have since ordered a replacement one just as an experiment to see if thats it but I really have no clue here...its hard to narrow down where exactly the noise is coming from cause its so loud and all the belt drive components are so close to each other.
 
You might consider an inexpensive automotive stethoscope. The ear pieces will filter out the ambient noise and allow you to focus on what is really making the noise. You just carefully place the rod on each part until you find what is making the noise. It is how I have pinpointed every one of my pulley bearing issues and I've had a few.
 
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pagrey said:
You might consider an inexpensive automotive stethoscope. The ear pieces will filter out the ambient noise and allow you to focus on what is really making the noise. You just carefully place the rod on each part until you find what is making the noise. It is how I have pinpointed every one of my pulley bearing issues and I've had a few.
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This is a good post ..those scopes are invaluable .

If I remember right , some of those bearings can be greased too. Also notice the bolts condition on the tensioner pulley .
 
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Look for any wobble in the belt at all pulley locations. Alt, crank, etc. It could be a bearing on several different points. Or the extra alt load on startup putting enough extra load to slip a bit when wet. I've had some belts on other vehicles that just like to chirp a bit. Put the cracked, dry rot belt back, quiet. New belt, chirp.
 
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Goatman said:
Look for any wobble in the belt at all pulley locations. Alt, crank, etc. It could be a bearing on several different points. Or the extra alt load on startup putting enough extra load to slip a bit when wet. I've had some belts on other vehicles that just like to chirp a bit. Put the cracked, dry rot belt back, quiet. New belt, chirp.
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I'll try that but this is just weird...

Tonight I park in a parking garage at the hospital, work all night and everything is obviously dry in a parking garage, I start it up this morning, no chirping at all. I drive out of the garage where its wet out from raining all night and after driving for 1 minute it starts chirping. Not loud and embarrassing but noticeable, then after 15 minutes of driving the chirp dies down. Its just that i'm trying to figure out what is causing that noise when wet or why once it gets wet does it make this noise.

I did get the new new tensioner pulley yesterday in the mail so i'll have to for fun swap it and see if that makes any difference at all.
 
Spin all the pulleys when you have the belt off. Alt, etc. Check for any little grinding, roughness, lateral (in and out) movement on each one. Belt issues can be a real pain to find sometimes.
 
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My belt is only squeaking sometimes when i give it gas and sometimes it does it CONSTANTLY. It started doing it right before winter(around mid December), I don't see any play in the belt and the belt itself looks in fairly good condition, anybody got any suggestions?
 
TylorGodfrey01 said:
My belt is only squeaking sometimes when i give it gas and sometimes it does it CONSTANTLY. It started doing it right before winter(around mid December), I don't see any play in the belt and the belt itself looks in fairly good condition, anybody got any suggestions?
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Check the tensioner or idler pulley... Those things have the ability to make a racket. Sometimes you can spray a little spray lube in one and if it quietens down that tells you it needs to be replaced... Just try not to get it on the belt.
 
If it started in the fall then it could be that the battery isn't holding enough charge in the cold weather and so demands a high output from the alternator right after startup. This high load from the alternator will make it much harder to turn the pulley, which could overload the belt's friction. Add to that the dampness that the dew will deposit on the belt, and the problem is compounded. This isn't a cure, more of a possible explanation. Then when the engine gets hot (using your parking garage post) it is able to keep the belt dried off better reducing or eliminating the squeal as you drive. Hope any of this is understandable.
 
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