How To Replace The Shaft Seal On A Polaris PB4-60 Booster Pump

This guide will take you step by step through replacing the shaft seal on a Polaris PB4-60 Booster Pump. A booster pump is required for certain Polaris pressure-side cleaners. Just like your swimming pool pump, they require periodic maintenance such as changing the shaft seal. A leaking shaft seal should be replaced as soon as possible to avoid damage to the motor.

1. The first thing you will want to do is to turn off the power to the motor. This can usually be done by switching the circuit that the booster pump is on to the off position.

2. Depending on how the booster pump is plumbed in, you can either disconnect the hoses or use the shut off valves (if installed).

3. Next, you want to remove the 6 nuts and bolts that are holding the front cover to the volute using a 1/2 or 13mm socket wrench. Once the nuts have been removed, the bolts can be pushed through to the front and out of the housing.

4. The next step is to remove the front cover exposing the impeller. Once the impeller is visible, you will need to remove the back cover that hides the end of the shaft. The cover can be removed using an adjustable wrench.

5. Once the shaft cover has been removed, use a 1/2 or 13mm open ended wrench to hold the shaft in place.

6. While holding the shaft in place, begin turning the impeller counterclockwise until it has been removed from the shaft. Make certain to remove the volute o-ring and inspect/replace it if necessary. If it is in good shape, place it aside for now so that it doesn't get damaged or lost.

7. Once the impeller has been removed, both halves of the shaft are visible. One half of the shaft is installed on the impeller itself. The other half is installed inside of the volute and is not accessible with-out removing the volute.

8. To remove the volute, we will have to remove the 4 bolts that hold it onto the motor and stand. Start by removing the top 2 bolts. Once they have been removed, you can remove the bottom 2 bolts.

9. After all 4 bolts have been removed, you can carefully lift the motor and volute off of the booster pump stand. Gently pull the volute away from the motor to remove it. There is an o-ring that sits on the shaft that may make it difficult.

10. If you turn the volute over, you will be able to see the metal seat of the shaft seal. Using the 1 1/4" pvc pipe (or other material with the same diameter) and hammer, lightly hammer out the shaft seal. Make certain that you are not hammering the surrounding volute housing otherwise the volute will need to be replaced.

11. Once the shaft seal has been removed from the volute, you can use the flat head screw diver to remove the other half of the seal from the impeller. Insert the tip of the screw driver in between the rubber boot and the body of the impeller and gently push down towards you. This should lift the shaft seal enough so that it is easily removed by hand.

12. Inspect both the volute and the impeller for signs of wear or warping. The shaft seal is water-cooled. If the pump ran dry, the 2 halves of the shaft seal will create high heat due to friction. The heat can often cause the area where the shaft seal is installed to become warped.

13. If both parts are good, you can begin installing the new shaft seal. Place the shaft seal (with the metal seat) upside down on a clean paper towel. Now apply a bead of silicone caulk around the metal seat. 

14. Carefully lift the shaft seal and place it into the volute. To install the new shaft seal properly, you will need to use the 1 1/4" pvc pipe or a 1.5" male threaded adapter. The pipe should fit over the spring portion of the shaft seal. Using the pvc will allow you to hammer the seal into place without damaging it in the process.

15. With the shaft seal and pvc pipe in place, lightly hammer the shaft seal into place. Some of the silicone caulk will get behind the metal seat (back side of the volute). You can use your finger tips to smooth it out.

16. Next, apply a small amount of lube onto the impeller where the other half of the shaft seal will be installed.

17. Using a clean paper towel, press the shaft seal firmly into place. The white ceramic part should be facing up.

18. Apply a small amount of lube to the shaft o-ring and press the volute back onto the motor. Once you have done this, gently place the motor back onto the stand. If the o-ring is damaged, it should be replaced.

19. Install the 4 bolts connecting the volute to the motor. Two of the bolts will be longer than the others. The 2 longer bolts will be installed on the bottom half of the volute connecting the motor, volute and stand together.

20. Lubricate then re-install the volute o-ring. Use the 1/2 or 13mm open-ended wrench to hold the shaft in place. While holding the shaft in place, begin turning the impeller clockwise until it is firmly in place on the shaft. DO NOT OVERTIGHTEN.

21. Place the volute cover back on and install the 6 nuts and bolts that hold the front cover to the volute using a 1/2 or 13mm socket wrench.

22. Your booster pump repair is now complete. You can reconnect the hoses and turn the power back on. Let the pump run for a few minutes while inspecting for leaks. If there are no leaks present, job well done. If there are leaks present, turn the power off to the booster pump to repair the leaks.

If you have any other questions about pool and spa products please do let us know - we are here to help! 

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