Over time, the bearings on the evaporative cooler can wear out from usage as the drive shaft is constantly turning while the cooler is working, causing the bearings to vibrate and build up friction. If the bearings are not regularly oiled, they can dry up and begin to break apart or start making noise. Replacing the bearings can be done by taking the brackets off the stabilizing bars on the sides of the cooler with some basic tools.

Turn off the water to the evaporative cooler at the water shut off valve, and switch off the circuit breaker at the breaker box before attempting to replace the coolers bearings. Remove the cooler panels from all three sides, and set the out of the way.Loosen the bolts on the motor with a socket wrench, and take the belt off the motor pulley to remove the tension on the drive shaft. Unfasten the bolts on the top of the bearing housings on both ends of the drive shaft with a socket wrench, and take the hold down brackets off the top of the bearings.Things You’ll Need:  Slide the old bearings off both ends of the drive shaft, and remove them from the evaporative cooler. Place the new bearings on the ends of the drive shaft, and secure the hold down brackets over the tops of the bearings with bolts.Oil the new bearings by placing 3 or 4 drops of non-detergent lubricating oil in the oil caps on the tops of both bearing brackets. Place the belt around the motor pulley, and pull back on the motor to add tension to the belt while tightening the bolts on the motor.Put the cooler panels back in place, and turn the water back on at the shut off valve. Turn the circuit breaker back on for the evaporative cooler at the breaker box.