Help finding possible pulley bearing failing...

[dasgeek]

I have a 2002 LX470 with just under 230,000 miles. Last summer started to hear a squealing sound from under the hood. It turned out to be the belt tensioner pulley which I replaced with help from the great thread in the FAQ. Yesterday I started to hear a similar squealing from under the hood. It sounds like a pulley bearing going bad. Kind of a high pitched chirp. I popped the hood and tried to figure out which one was making the noise, but I could not tell. Any thoughts on how to track down whick pulley is failing, or what else it might be?

I have to go out of town for a couple of days on Monday and am concerned about it failing while I am out of town.

 

[AimCOtaco]

A mechanics stethescope could be useful, or as a substitute, a piece of tubing.

Best guess is the bearing in the fan bracket, I would start there, next Alt, then steering pump. Could be the belt tensioner again depending on the source of the last replacement.

 

[2003lx470]

Any video?

 

[dasgeek]

I used a mechanics stethoscope from Harbor Hate with the solid metal end on it not the open tube (all I have handy) and did not hear anything. I will try and get some video, but it is not doing it as bad as yesterday. Yesterday, I made a short trip and it was squealing more as I increased RPMs. The car was cold from garage and outside temp was about 25F. I just pulled the truck out and it is not doing it like it was. It is just a little hint of a chirp. If it starts again I will get video.

 

[dasgeek]

OK. Here is a video. You can hear the chirping a little. It was much louder yesterday. Audio might be loud so watch playback volume.

 

[ttahara]

Take off the belt and spin the pulleys and I bet you'll find one that doesn't sound right.

 

[00Bruiser]

Hi forgive me for never introducing myself... But I believe I know what that noise is and unfortunately what will happen if left unattended... Last January I purchased my very first LC and after about two months I noticed a sound very similar to that in the YouTube video... One morning on my way to work I noticed the sound it was really really cold outside so I thought that maybe the belt was just stiff and chirping a little bit but on the ride home the weather was significantly warmer and the sound still persisted I only noticed it when I was at low RPM's (idle-1800) and once I got about 2 miles away from home the bearing on the pulley completely gave out and caused a extreme amount of play resulting in the serpentine belt coming off... Causing the loss power steering and I believe alternator... Once that happened it was very obvious what part had malfunctioned and this is the part. 1607A




1607A

 

[00Bruiser]

Sorry...#16307A

 

[dasgeek]

Hi forgive me for never introducing myself... But I believe I know what that noise is and unfortunately what will happen if left unattended... Last January I purchased my very first LC and after about two months I noticed a sound very similar to that in the YouTube video... One morning on my way to work I noticed the sound it was really really cold outside so I thought that maybe the belt was just stiff and chirping a little bit but on the ride home the weather was significantly warmer and the sound still persisted I only noticed it when I was at low RPM's (idle-1800) and once I got about 2 miles away from home the bearing on the pulley completely gave out and caused a extreme amount of play resulting in the serpentine belt coming off... Causing the loss power steering and I believe alternator... Once that happened it was very obvious what part had malfunctioned and this is the part. 1607A




1607A

Thanks for you input. How long did you hear the noise before it failed?