Hey, I just bought a '95 SC300 and I am getting a squeak from the serpentine belt. I did the "spray water on the belt" trick and it made the noise go away for a couple seconds so that means that the issue is most likely a pulley going bad or pulley misalignment. I changed the tensioner pulley and it made no difference. It seems like the harmonic balancer is further forward (toward the front of the car) than the other pulleys, which seems like it could be causing the noise. Is it normal for it to be positioned like that? Can the harmonic balancer position be adjusted, or does it just sit where it sits?

The previous owner recently changed the belt, so I don't think that would be the cause unless the belt is just defective.

Here is a video of the noise...
http://vid90.photobucket.com/albums/...psf1dxhbgn.mp4
In the video you can see that the belt also hangs off the tensioner, as if the harmonic balancer is dragging it off. Any information or advice would much appreciated. Thanks in advance.

 

its your new belt .. I just had the same issue 2 days ago when I changed my belt to a new oem one from Toyota .. made the same noise , went back to my old belt and noise went away .. crank pulley can only be installed one way , just on unless the woodruff key is out of its normal grove on the crank snout and preventing the pulley from being all the way on , I have seen that happen before

 

Hmm before I read your post I was leaning towards the crank pulley was going bad. Here are two pics to show why I was thinking this...

http://www.billet.net.au/linked/belt_tensioner__1_.jpg
http://i90.photobucket.com/albums/k2...m.jpg~original

I just posted links, because the photos are fairly large. The first pic I found online, but you can see that the belt comes off the crank pulley and goes straight to the tensioner as it should. But in the second pic, which is my sc, you can see that the straight line path of the belt from the crank pulley causes it to hang off the tensioner. Therefore, I was thinking that maybe the outer layer of the crank pulley has started separating from the inner and shifted forward.

However, I would like to be fairly certain before spending $300 on a new crank pulley, so I'm gonna look into it more today.

 

Over time the rubber on the balancer breaks down and the outside ring separates from the rubber. Ive had this happen twice, I bought a low milage used one and it happened a year or two later. I think its best to buy a new one, I actually saw some non-oem ones for less than 100 lately. I end up just buying a fluidampr because it was just a little more than a OEM one and it elimated the need for the rubber part of it. I've always plan to do a 2jzgte swap in mine so its nice to have the upgraded part.

 

separating pulley will do this as well .. easy test , have some one rev motor while you watch crank pulley , if separating you will see the inner ring move in and out ever so slightly .. I have that same tensioner pulley from phr ... I changed my damper to fluid damper as well to eliminate chance of separation

 

Well the crank pulley is definitely bad. Upon closer inspection the outer part clearly has shifted forward and when revving the engine the inner and outer parts are definitely slipping. Thanks for the help.

Quick question about buying a new pulley. Has anyone tried the ebay crank pulleys that cost around $50? Does anyone think its worth trying or will it probably just go bad in a month? Here is a link to one of them....
http://www.ebay.com/itm/Harmonic-Balancer-Fits-Lexus-IS300-SC300-GS300-Supra-Crankshaft-Pulley-3-0L-L6-/331483639421?hash=item4d2df6ee7d&vxp=mtr

 

^^eBay crank pulleys' have been getting a lot of bad publicity on here. Several users have bought them and had them go bad in a few months.

I would not get anything with a rubber damper that wasn't OEM. The Harmonic Balancer takes a bit of work to get to and replace, and having one separate while driving is not fun either. I'd go with a fluid damper like the guys above, or go OEM, unless you need a temporary solution to float you a month or two until you can afford OEM or fluid damper. I bit the $400+ bullet and got an OEM one when mine went out, and at the very least I know I won't have to be buying another one for another 20+ years or 150k miles.

 

Don't buy those cheap pulleys. I bought one and the rubber is already falling out. Did this in only 1 year.