Thanks for the clues above. @Richard1079, I have a set of bushings on order, didn't think I'd need the spring at $30 or that I can source an equivalent for much less (even at Grainger). @ccwatchmaker, are you using an o-ring in place of the spring? I just noticed that my fan is hit-and-miss, sometimes it turns and sometimes the spring slips. I lubricated the bushings, cut about a quarter inch from the spring and also cleaned it and both pulleys, all to no avail. My next though is to source an o-ring.