BRZ Squeal, Belt and Idler pulley question
 

So I recently changed one of my idler pulleys and now I'm smelling a burning rubber, especially after longer drives. This is a relatively new occurrence and I'm wondering if I should put the old idler pulley back in because it was slightly smaller in diameter.

I originally replaced the top smooth idler pulley because my mechanic thought it was that pulley and nothing to do with the timing system as I've had a bad experience with waiting too long on a squeal when I had a 97 Forester.

I'm also toying with the idea of just buying a pulley kit since all of my pulleys are looking old and rusty and making a lot of squealing noises but I really haven't seen a lot of information about the other pulleys besides the crank pulley.

Any help would be appreciated. I did order a 2nd idler pulley since I only replaced one and a new belt from work since I work at an autoparts store. I'm also gonna hit them with some belt dressing just incase.

Ugh. Belt dressing just makes a mess.

The bearings on all the accessories, including idlers, should run silently. If it squeaks or makes a 'whoosh' when spun, it's toast.

The only audible exception to this is the alternator. There is contact between the brushes and slip rings. Still, it should spin smoothly and make very little noise.

I hear a squeal especially when idling that goes away when I bring up the engine RPMs, which is why I thought it was a timing belt before I found out the twins use chains.

Just replace the belt, don't use the dressing.

isn't belt dressing bad for the belt?
Plus its only a temporary fix too I believe.

If a timing belt were ever to slip, much bigger problems would be looming because their functions are identical. Then again, maybe you were just referring to a failed tensioner.

The squeal you hear immediately after startup is coming from the alternator. It is working hard to dump charge back into the battery. I get a little on dewy cold mornings once in a while.

If it gets louder when you crank up your blower motor and the headlights, that's 100% confirmation.


(edit) I misread. Do you hear the squeal always?

Spray the belt with Windex or water. If the squeal goes away for a second then it might be a bad belt or a belt that squeaks. I went with a Gatorback belt when I got my supercharger because I had belt squeal on a replacement belt; it fixed the squeal.

If it isn’t the belt then move to the other suggestions.

Its generally after a longer drive when idling that I hear the squeal, but its not all the time and I haven't smelled the burning rubber smell since. I've heard it when its rainy or wet outside and just assumed the belt got wet.

I have a new smooth idler and a belt from work that I'm going to install this weekend but I also want to clean up the engine a bit as well, get some of grime off of it.

Keep us posted.

I changed the belt and idler pulley and seemed to make a difference but at the same time it didn't seem like it.

I'm wondering if what I'm hearing isn't from the belt and pulleys but the fuel pump chirping. The Dayco belt does seem to be of higher quality than the belt the Toyota dealership installed so if nothing else that's a positive.

Post a clip of the sound on youtube. We can tell you in 2 seconds if it's crickets. If that's not it, then there's a chance we can still help.

I'll try next time its dry enough to eliminate a wet belt as the reason.

Hey y'all not to hijack a dead thread or anything I'm having the same sorta sound. Was wondering if y'all could help diagnose. The squeal did go away after spraying water but this just sounds rough for a 55k mile car.
https://share.icloud.com/photos/0Uts...DWlbMH4Qw#Home

If the squeal goes away with spraying just a bit of water replace the belt. I dont hear anything out of the norm. Our flat fours sound like tractors at idle and your hearing the typical crickets from the HPFP.

Sent from my GM1915 using Tapatalk