If your pump is grinding or making a loud whining noise, you most likely have a bearing failure in your pump. This will give you a guide on how to change them.
Tools and Parts:
- Shaft seal
- Socket set and ratchet
- Bearing puller
- Snap ring pliers
- A short pipe the diameter of the inside bearing race (usually ½”)
- Hammer
First, remove power to the pump by turning off the breaker. Then remove the wiring to the pump as well, as you will need to remove the motor from the area. Once the power is off and then disconnected, you need to separate the motor and pump from one another. To do this remove the 6 bolts (usually 9/16”) or the clamp on older pumps, whichever you have. Once the motor assembly is removed, remove the impeller by using a wrench to hold the shaft at the rear and spinning the impeller counterclockwise to spin it off the shaft. Note: your impeller may have a screw locking it in place. Be sure to check for and remove the screw before attempting to unscrew the impeller from the shaft. Next, remove the seal plate and mounting plate. Once removed, you will see a rubber seal on the shaft called the water slinger, make sure you keep it for reassembly.
Once the motor is separated and by itself, you can start disassembling it. The first step is to loosen the bracket for the capacitor and set the capacitor to the side. You will then need to access the motor governor. Most pumps have a copper V-shaped switch that sends power from the terminals to the motor assembly. That needs to be removed (but not disconnected) to access the screw on the end of the shaft that holds the governor on. Remove the screw holding the governor in place. This will allow the shaft to be removed from the motor housing. Before removing the shaft assembly, mark the motor case and frame on opposite sides with specific marks. This will make sure the case goes back to the same orientation it came off. The last step before being able to separate the motor and case is to remove the 4 through bolts along the perimeter of the motor.
Take the hammer and lightly hit the tabs on the end plate to break the seal and get the shaft assembly to separate from the motor shell. The rotor and shaft assembly is where the bearings are pressed onto so that’s the part we need to hold onto.
Remove the front-end bell with a bolt. Then stand the shaft on end and tap the tabs with the hammer to separate the bell from the shaft. Starting with the rear bearing, it is time to use the bearing puller. Make sure the tabs of the puller are on the outside race to clear the retaining clip. For the front bearing, you must first use the snap ring pliers to remove the snap ring that holds the bearing against the retaining clip. Once you remove the bearings you can find the part numbers on them and order a new set of bearings. If you purchased bearings beforehand, make sure the part numbers match before reassembly.
You will need the short pipe for this next part. Ensure the pipe is the same size as the inside race of the bearings. This ensures you do not put undue stress on the bearings during installation. Start with the front bearing by standing the shaft on the end and using the pipe and hammer to press the bearing onto the shaft and put the snap ring back in place. Repeat the process for the rear bearing, making sure both snug them up to the retaining clip on the shaft.
We can now begin reassembly of the motor. In doing so, place the bearing retainer plate and start the bolt for it. You will see on the front shell where the bearing rides, and now is the time to mate those two. Squeeze the front shell plate and motor fan assembly together to seat the bearing properly. You will feel the movement stop as it bottoms out. At this point, you can tighten the locking plate for the front bearing. If there was a unique washer or load spring at the rear of the motor, make sure to put it back. Then, line up the shaft to press the rear bearing into the motor case. Make sure it's fully seated, and line up your marks from earlier. Make sure the orientation of the motor case and endplate are the same as when you took it apart. Use the 4 through bolts to tighten it all together. Then, you can reinstall the governor, V switch, and capacitor in the opposite order from how you disassembled them.
Make sure to put the water slinger back on the front of the motor, then slip it on the motor mount plate. While the seal plate is off, it is a good idea to replace the seal before reassembly. Once the new seal is in, you can reattach the seal plate and the impeller(hand-tight is all you need) and attach the motor assembly back onto the pump housing. Make sure you tighten the bolts correctly, reattach the electric to the back of the motor, and fill the basket with water before starting. If done properly your pump should now run as quietly as it did when it was new.
