I'm just a new guy here. I am bringing a '37 back from 50 years of sitting in a barn and I'm no expert but I'm learning as I go.
I had a high pitch screech up front and a few drops of oil in the generator oil caps solved the problem.
It sounded a lot like your noise. I can't see in the video if you have a second belt running your generator.
Maybe I just got lucky.
