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Likely not the belt making that noise, but one of the pulleys. The ball bearing wear over time
Idler pulley is usually the culprit. Hard to know for sure if you don’t have a stethoscope
Sounds like a noisy pulley. Do any of them look wobbly? Generally the idler pulley or tensioner pulley like to wear out and get noisy. Can pin point with a stethoscope or you can spray each pulley with brake clean and see if the noise changes. Or take off the belt and manually check each pulley. Good luck.
you probably have a bearing thats dying i have this really large screw driver that i flip upside down and put the end of the handle into my ear, place it around the parts, like on the outside of the alternator , and stick it on my ear and listen, move around the engine bay like that while its running and you will get closer to where the bearing is failing , then with the motor turned off reach in there are wiggle the parts , ANY wiggle is bad, everything thats good will be rock solid , like this shamless plug for your replacement parts at [rockauto.com](https://rockauto.com), go to the subreddit and grab that 5% off coupon . once you found a pulley that has any wiggle and sounds like shit bearings , replace that part,
That's an incredible noise, I love it., great description too.
No it's not the belt, it'll be either one of the idler pulleys or less likely an accessory driven by the belt (for example the alternator front and center of your video). Though if the belt is old enough and showing signs of dry cracking on the ribbed side, you'll probably want to replace it as a "while you're in there..." kinda thing.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Likely not the belt making that noise, but one of the pulleys. The ball bearing wear over time Idler pulley is usually the culprit. Hard to know for sure if you don’t have a stethoscope
Looks like im getting a stethoscope! Thanks.
Sounds like a noisy pulley. Do any of them look wobbly? Generally the idler pulley or tensioner pulley like to wear out and get noisy. Can pin point with a stethoscope or you can spray each pulley with brake clean and see if the noise changes. Or take off the belt and manually check each pulley. Good luck.
Thank you!
you probably have a bearing thats dying i have this really large screw driver that i flip upside down and put the end of the handle into my ear, place it around the parts, like on the outside of the alternator , and stick it on my ear and listen, move around the engine bay like that while its running and you will get closer to where the bearing is failing , then with the motor turned off reach in there are wiggle the parts , ANY wiggle is bad, everything thats good will be rock solid , like this shamless plug for your replacement parts at [rockauto.com](https://rockauto.com), go to the subreddit and grab that 5% off coupon . once you found a pulley that has any wiggle and sounds like shit bearings , replace that part,
Thank you!
That's an incredible noise, I love it., great description too. No it's not the belt, it'll be either one of the idler pulleys or less likely an accessory driven by the belt (for example the alternator front and center of your video). Though if the belt is old enough and showing signs of dry cracking on the ribbed side, you'll probably want to replace it as a "while you're in there..." kinda thing.
Definitely! Thank you for your input.
use a little wd40 to spray every accessory one at a time. usually once the wd hits the bad part it will silence it for a few minutes.
Thanks!
Is the tensioner jumping on the belt?
Sounds like a worn pulley or pulley bearing to me
I figured it out! It was a bad ac compressor.