After only one season a fan may be covered in enough gunk to give the illusion that the 'motor' is worn out, when really all that is needed is a good cleaning to keep it running for a lot more hours. I have often picked these up on trash day, and gotten years of use from them. Rarely I may have to replace a knob, but usually they are functioning, but the blade speed is about half of normal.
Step 1: Tools
All Purpose Cleaner/degreaser
Finger Nail Brush
green kitchen scrubbies
Step 2: Remove Front and Back Grills
Sometimes a few can be missing OR the hole has grown too large to reseat tightly.
Yes, you can skip a few, usually you can leave off a side screw without TOO much noise factor.
but you NEED the top and bottom tightly screwed down of the vibration will make a hell of a racket.
scout around for replacements - you want short and fat threads.
Step 3: Remove Grill and Fit
if the feet are missing you will have to dummy a replacement, or just make sure the fan is propped up, like in a window. Vibration at high speeds will make the fan walk and possibly fall.
Step 4: Brush the Motor
Use a brush to remove the hair and gunk.
also wipe the struts.
Step 5: Wash Blades
I find that some blades resist degunking and a scrubbie pad is useful to remove the stuck on gunk.
If you leave it gunked and only remove the visual material, new stuff will quickly latch on and you will be just as bad off. You want to end up with smooth clean plastic blades, where things slide off.
Step 6: Clean Fan Grills
The grids are NOT straight but beveled, and may appear clean if you look at them straight on, look at them from an angle and you will see they have four sides, you don't need it spotless, but get the area in front of the blades reasonable clean. You CAN do these in the shower, and use a long handled scrub brush, but you will still need to use paper towels to get in some crevasses.
Step 7: Reassemble the Fan.
Reattach the grills, the feet and align the power cord collar.
Turn it on, if the fan was not old to begin with you will find a world of difference between the speed of the fan blades before and after the cleaning.
I do this every season to my own fans and these $20 box fans last a lot longer then the manufacturers want them too.