Here's the source of that annoying screech

 

 

here's your culprit, the bearing beneath that hub has failed, removal is fairly straight-forward

 

 

Profile of where your fan hub attaches, note you will have to remove it from your QSB

 

 

Lock down the hub mounting point on a vise to remove this backing plate, you will have to re-press the bearing back into this mount, or have someone do it for you.

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