Swimming Pool Blog
by Rob Cox, May 26, 2012
Anthony Pools Bronze Pump motor replacement
If your pool pump motor is screaming and shrieking, it's begging for attention. Or perhaps your motor has given up the ghost altogether. In either case, you have a few options.
You could take the motor to a local electric motor shop, and have them rebuild it - this general involves replacing the bearings and the shaft seal, maybe a fresh coat of paint on the motor casing. This cost can vary from area to area, but let's assume that this option will cost you $125 +/-.
Rebuilding your pump motor can be a good option, especially for a relatively new pump. The only problem with rebuilding a motor is that the only thing being "rebuilt" is the bearings and the seal. The other parts of your pump motor are still the same age. Windings, Capacitor, Switches, etc - could cause problems later on, and the warranty on a rebuild job is usually only 30 days.
Option #2 is to replace the pump, from front to back, motor and "wet end". This could be a reasonable option if your old pump was undersized and underpowered, or if you want to (or are required to) switch to a dual-speed or variable speed pool pump. Of course, this is the most expensive option, running anywhere from $350 to $900, depending on the pump model and features.
Option #3 is the subject of this blog post - replace the motor. When we speak of the motor, we refer only to the electrical motor attached to the "wet end", where the water is pumped through. Modern pool pump motors are now more efficient than ever, and if you wanted to, you could switch to a two-speed motor, although you will need to replace the time clock, and add the 4th wire - the low speed power wire.
To replace your pool pump motor, you'll need to have a few items on hand:
- Pump Motor. Pool pump motors are classified by Frame Type, 48 frame, 48Y frame and 56 frame, otherwise known as aboveground pump motors, C-flange motors and Square flange motors. Of the two type of C-Flange motors, you can find threaded shaft motors, with male threads on the end of the shaft, and also Keyed shaft motors, which have a groove along the shaft, and no threads on the end. Our Anthony bronze pump motor is a keyed shaft type, and uses a brass stub shaft to connect the motor shaft to the impeller.
Order the correct frame type and the correct horsepower motor for your pump. If you want to change the horsepower, you will also need to change the impeller in most cases.
- Shaft Seal. This 2-piece mechanical shaft seal sits behind the impeller and keeps water from running out along the shaft. For our Anthony pump motor replacement, we are using a #1000 seal. Other common seals are #100, #200, #201.... and many others. Different pumps will use different shaft seals, check our shaft seals page to buy the correct seal for your particular pump.
- Volute Gasket. Our Anthony bronze pump uses a paper gasket, but more modern pumps will use rubber o-rings. Paper gaskets absolutely need to be replaced when changing the motor, but if your rubber o-ring is in good shape, you may be able to reuse it. Go-Kits are convenient to use when replacing a pump motor. Go-Kits contain the shaft seal and all gaskets or o-rings for a particular pump.
How to Replace an Anthony Bronze pool pump motor:
- Shut off power at the breaker, and the time clock.
- Remove the bracket nuts that connect the open volute or bracket to the hair & lint strainer.
- Remove the rear motor cover, and unscrew the wires, 2 power leads and 1 ground wire.
- Loosen the flexible conduit nut, and pull the wires out of the motor.
- Remove the set screws which secure the stub shaft to the keyed motor shaft.
- Remove the rear bracket bolts which secure the bracket to the motor.
- Pry the bracket off of the keyed shaft with a large flathead screwdriver.
- Remove the impeller from the stub shaft by holding the shaft firmly and unthreading the impeller.
- Replace the shaft seal between, thread the impeller back onto the stub shaft.
- Slide the bracket / stub shaft assembly over the keyed shaft of the motor.
- Reinstall the bolts that secure the bracket to the new motor.
- Push the impeller very close to the motor, and reinstall the set screws to secure the stub shaft.
- Wire up the motor and replace the rear motor cover. Give a quick power test to check wiring.
- Replace the paper gasket and reattach the bracket to the hair & lint strainer.
- Fill the hair & lint strainer with water, open the valves and turn on the pump.
The job of replacing a motor on a different pump is not so different, really. Most modern plastic pumps don't utilize a stub shaft, or a keyed shaft motor. The most common question I hear from pool owners replacing Hayward, Pentair or Jandy pump motors is how to remove the impeller. The trick to this is to hold that shaft stationary, in the rear of the motor, while unthreading the impeller from the opposite end of the motor shaft. Once the impeller is removed, you can then remove the seal plate from the old motor and reinstall it onto the new motor, using a new shaft seal.
I hope this has been helpful to those who want to save a few dollars and replace their own pumps, or for younger pool guys who dont often come across the old style Anthony bronze pump (made by Sta-Rite for Anthony).
If you have any questions on your pool pump motor replacement, hit the link at the top of the page and send me an email, or leave a comment below.