You can see what the guy in the video is doing by taking your visor, push up on the very end to support it, and pull down on the visor with the other hand at the pivot point. It will straighten right up for a second or two. Like he said, the center hole in the 3 hole casting is worn out. This is letting the spring pull the 90 degree portion of the arm too far up into the casting, which then lets it sag. That washer he added stops the spring from pulling the arm up too far.
I have been wondering how to fix this myself. If you use his method, I would make a easy way to get the spring off again, I suspect over time his washer is going to wear out and need replacement again. Once it wears enough to make it's way around the 90 in the arm, you are back to square one again.
I had thought about using one of these split collars. You would not have to take anything apart, and it's much thicker than the washer so i don't think it would ever wear enough to make it around the 90. I don't know, I hope it's not too thick to fit.
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