Pully or damper noise?

[PatinaBeforePolish]

I've listened to it a bunch of times and it sure sounds bearing related. Have you tried taking the belts off of each accessory one by one? I'd start with power steering, then ac, then alternator/water pump.

[REman]

My cousin was just here and he said it sounds like a pully bearing to him.

[canada karl]

I'd bet money on the alternator bearing.

[528i-1981]

My cousin was just here and he said it sounds like a pully bearing to him.

To me, spraying lube behind the pulley suggests that's where the problem is. I can convince myself that the video also locates the noise as from behind the pulley as you pan around, but that has low (perhaps negative) diagnostic power. One thing you might try is to turn on the AC to see if it's the compressor clutch (maybe pull the aux fan fuse first, that thing is loud).

A change in intensity and pitch as Jon asked earlier would accompany anything belt-driven, but removing belts seems like your next move. Let us know how you make out.

[REman]

Thank you for all the good feedback and ideas! I just have not had the time recently to explore the issue further but promise to get back to you all once I figure this odd noise out.