Name that noise.

[jlwdvm]

My zero mile Texas Speed 570 horse LS3. The belt was taken off and cleaned with Dawn. All the pulleys and idlers were cleaned with alcohol and Dawn as well. The sound persists! I used a screw driver and my ear in an attempt to isolate it, but I can't. Everything turns freely by hand with no noise/grinding. Thoughts?

https://www.youtube.com/watch?v=aGTQVrdE-3g

[Che70velle]

Did you put oil in the engine? Just kidding!
Sounds like a bearing to me, maybe alternator? Tough to diagnose, even with video...

[raustinss]

yeah i would agree with scott, on a different note i had a old vacuum line go for a s**t on my chevelle quite some time ago and it created the most annoying weird squeeling flutering humming noise , had the dealership mechanics in fits trying to find it then when we did no one could believe it almost like it was coming apart from the inside . if you can try to get a piece of a hose or a stethoscope ,would work better then a screwdriver

[Vegas69]

It does sound like a strange vacuum leak.

[rallystyle]

Did you take the belt off and run it to see if that was the noise?

[jlwdvm]

Forgot to mention that! I ran it to verify that the noise was there at idle and higher rpm. I then pulled the belt and ran the motor to verify that the noise was gone...and it was.

[raustinss]

try a new belt ?

[TomM]

Idler or tensioner bearing is bad....IMO


T,

[NAPA 68]

^^^^^^^^^^^^^ This!

[CamaroAJ]

Check your belt alignment to see its its misaligned. Make sure the power steering pulley is all the way on too.