Hampton Bay Fan model K2 52" 5 blades was already installed when bought house 6 years ago. I switch to push air up in winter. The 2nd time fan was turned on after switching to up, the fan unwound from the drop post. I screwed the sleeve attached to the motor housing back onto the post. There are 4 'set' screws on sleeve. If I tighten the screws, I fear I'll strip threads. If I don't tighten, I fear the motor will unwind again. Any ideas? Thanks