Hot answers tagged exhaust-fan
WD-40 is a penetrating oil and corrosion preventative. As a lubricant, it is quite short term as it tends to evaporate. And the lubrication type for an electric motor depends on the type of bearing. Ball bearings require grease. Flush the bearing with solvent to clean out the old gunk and pack with a light bearing grease. Oilite style sleeve bearings ...
Pull the cover: inspect the fan to see if it is full of lint or debris, you may simply need to clean it. While you're there: Get the model number of the fan and verify that it has the correct CFM for the size bathroom it is installed in. If it is under rated, consider replacing the fan with one that is more powerful; some decent fans start as low as 50$ ...
Check around the farm supply places - they carry big dampers. I used to have one about 36" square (the ex still has it). Try places like here and here.
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