Pulley Question

[BMW Kid97]

So, i've got the dreaded squealing coming from my engine bay, and we're finally supposed to have a nice day out here so i'm going to take a look at the pulleys tomorrow. My question is, I see a lot of posts about spraying the pulleys with WD40 to see if the squealing stops, and if it does that is the problem pulley. My question is, is it really okay to just spray down the pulleys like that? Or should I only be spraying certain parts of the pulley? Any help is really appreciated here guys!

[ovation1000]

Do you mean spray the tensioner? Spraying the pulley won't do anything besides make your belts slip even since the belt rides on the pulley, plus the pulley is sealed.Have you checked the condition of your belts? Mechanical or hydraulic tensioner?

[BMW Kid97]

I thought i read somewhere you could spray the bearings on the pulley...maybe i misread. I haven't had a chance to look yet, I posted this because tomorrow we're supposed to have a decently nice day out in the midwest, so i was planning on tackling this then.

[Eric93se]

The bearings are sealed so I don't see how that would really work. If your idler pulley and tensioner pulley are original you should replace them, and the belt too depending on how old.

[BMW Kid97]

yeah, i was planning on replacing everything when it's warm out, as i said i get somewhat of a nice day and was hoping to get rid of the sound for a little bit :D

[ovation1000]

Some people have removed the seal on the pulley and regreased them.I tried that but it didn't last long, maybe two weeks.If your belt is squealing(slipping) the problem is most likely the tensioner or a worn belt.

[BMW Kid97]

I see. I guess i'll just have to wait until tomorrow when i can rip it apart to find the problem. Any idea how much tensioners run off the top of your head?

[ovation1000]

Depends on if you have a mechanical or hydraulic tensioner.Mechanical (spring loaded) ones are cheaper, about $60 depending where you buy it.

[BMW Kid97]

ah gotcha. Is this something I should order online, or can i just pick one up at a local autozone/advanced auto parts?

[Eric93se]

rockauto has the right pulleys for your car, they're about $15 and ~$22, DON"T buy the URO brand. You need one offset idler pulley and two centered tensioner pulleys.

edit: I take that back I thought you had a 328i, so I don't know which you have then, check realoem.com

[ovation1000]

Pretty sure your going to have order it, don't think an Autozone would carry that.Confirm that's your problem though it might just be the belt.

[BMW Kid97]

yeah, i'll check everything tomorrow. thanks!