Apparently wd 40 was the wrong oil to use.
Lubricant for fan motor.
Step 3 apply a light nondetergent household oil that is sae20.
Instead pick up electric motor oil like 3 in one electric motor oil about 3 at amazon.
Then remove the fan s blade and wash it with soap.
Add no more than 1 to 2 drops at each oil port.
It is now so far removed from the way most americans think it.
First find the point where the shaft is holding the motor and clean that area.
Step 2 lay the fan down on a flat surface with the exposed face up.
This lubricant oil is produced by liberty oil products and it is a 100 synthetic oil compound.
It s too thin for electric motors.
The furnace blower motor is going to be working in very hot conditions so the type of lubricant you use is important.
Then put in a few drops of number thirty oil on both ends of the aforementioned shaft sticking out of the motor.
It not only removes any remaining lube but it can melt coil wires the lightly coated copper wires twisted up in electric motors and cause an electrical short.
It is excellent for smaller electric fan motors because it helps to reduce friction when there is a moving surface.
If there is a c clip pry it off first.
Whenever you have to lubricate an electric pump bench grinder or other electric motor don t pull just any oil off the shelf.
Don t use automotive motor oil.
Instead you might look for a particular brand of lubrication which is right for your motor.
Grasp the blades firmly and lift slowly to remove them.
Then swivel the shaft and cleanup any excess oil.
Afterwards you can oil the fan.
Lubricate a box fan motor step 1 remove the front grill of the fan.
Fan maintenance it s important in this throwaway society to realize the value of maintenance.