This guide provides a step-by-step procedure for replacing a pool motor shaft seal. If you see water leaking out of the bottom of the pool pump assembly, it's a good indication that you may have to replace the shaft seal within the motor pump assembly. As shown in the pool pump cut away, the shaft seal is located in the motor pump assembly behind the impeller. Although this description is specific to a Hayward pool pump, many of the steps can apply to other models of pool pumps.
1. The first step is to turn off all power to the pool pump. For maximum safety turn off the power at the circuit breaker to the motor.
2. Next you will want to remove the motor pump assembly from the wet end housing. Remove the four 9/16" bolts that bind the motor pump assembly to the housing. Note: some Hayward pool pump models have six bolts.
3. Now pull the assembly apart from the pool pump housing.
4. After the assembly is out, you should see the pool pump diffuser and diffuser gasket on the end of the assembly. If you do not see the diffuser or its gasket, check inside the housing.
5. If the pool pump diffuser came out with the assembly, pull the diffuser off the assembly. You may have to pry it off gently with a screwdriver. Now you will see the pool pump impeller. The shaft seal is behind the impeller so you will now have to remove the impeller.
6. To remove the pool pump impeller you will twist the impeller off in a counter clockwise motion. The impeller cannot be freed from the motor shaft without first securing the motor shaft.
7. Move to the other end of the motor shaft in the back of the motor assembly. Take off the two screws that hold the back cover onto the pool pump assembly.
8. You will see the pool pump motor wiring and capacitor. You will have to remove the capacitor to gain access to the end of the motor shaft. Capacitors store power. To avoid a possible shock, lay a screwdriver across the two leads to short out the capacitor. These capacitors sometimes burst when shorted out, so it is a good practice to place a cloth over the capacitor and to wear eye protection.
9. Now unscrew the single screw that hold the capacitor in place and push it out of the way. No need to disconnect capacitor from leads.
10. Place a 7/16" wrench on the flat end of the pool pump motor shaft to secure the shaft from rotating.
11. At the pool pump impeller end, twist off the impeller, counter clockwise. You may have to use a strap wrench to gently free up the impeller.
12. Now you will see the motor shaft seal. One half on the pool pump impeller and the other half in the seal plate on the shaft.
13. Inspect the threads on the inside of the pool pump impeller. If these are badly worn, you will have to replace the impeller.
14. Stand the motor up on end and gently remove the white ceramic seal inside the seal plate. You may have to use a small screwdriver to gently pry out the seal. If the seal plate lifts off, it may be simpler to push the seal out of the seal plate from the other side.
15. Set the new seal on the shaft inside the seal plate - white side up. Be very careful NOT TO TOUCH the white ceramic side of the seal with your hands. If necessary, gently seat the seal with the blunt end of a screwdriver.
16. Grab the seal on the pool pump impeller and twist it off. Make a note of how the seal is positioned on the impeller so you know how to place the new seal. It is possible to place this seal upside down. Note: You may have to also have to remove the metal collar if the new shaft seal also has one. Several people have written in saying that the new seal won't fit because they were trying to place the new collar on top of the old one.
17. Now push the other half of the new seal onto the pool pump impeller. Place the new seal on in the same postion noted above. Again, DO NOT touch the bearing (top) surface of this seal.
18. With the wrench securing the back end of the motor shaft, screw the pool pump impeller back onto the shaft (clockwise). Hand tight is sufficient.
19. Inspect the diffuser gasket for wear. Replace if required. Put a thin coat of lubrication on the gasket.
20. Snap on the pool pump diffuser - no screws are required. Ensure that the part of the diffuser labeled "TOP" is aligned with the "TOP" labeled on the seal plate.
21. Slip the motor assembly into the housing.
22. Replace the four bolts evenly. If bolts were numbered 1 though 4, replace bolts in this sequence - 1, 3, 2, 4 - to ensure that the motor is set properly inside the housing. Loosely tighten bolts in this sequence, then go back and tighten them down again in this sequence. If pool pump has 6 bolts, replace bolts in this sequence - 1, 3, 5, 2, 4, 6.
23. Replace the capacitor on the backside of the assembly. Make sure the plastic strip is in place between the clip and capacitor so that the capacitor does not short out.
24. Replace motor cover and secure with two screws.
25. Prime pump by removing strainer lid and filling strainer with water. Replace lid.
26. Reset circuit breakers and start pool pump.
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