Belt Squel

[bil1024]

I have a stock 302 setup with 6 rib pully, March bracket for alternator. water pump, idler and crank. It is making a heck of a noise from the alternator, the pully is fine without the belt. Alignment is pretty much dead on. If I loosen the tension its better but still there. Not sure what it is, I apply belt dressing to it and goes completly away, any thoughts ?

[Avalanche325]

Do you have a bad tensioner?

How are the alt bearings? Does it spin free? You don't have an 8000 watt stereo putting a huge load on, do you?

I have seen a V-pully that is worn out, but not so much a serpentine one. But maybe.