How to replace the seals in your pump

Rick the Spa Guy

The following is my easy (LOL) to follow steps for, How to replace the seals in your pump.


The following tips are general there are MANY pumps out there and a lot of pumps use different seals, this being said I will discuss the most popular types of pump seals out there.


The first thing to do is identify what pump you have and then which seal assembly is used in that type of pump. If you look on the label of your pump there usually will be a name for the pump like Aqua-flo, Theramax, Duramax, Flow master etc. Once this info is obtained you can google that pump name to find out which seal assembly is needed. Example's of seals are PS200, PS201, PS1000.

PS 200 seal assembly

Now once you have the seals you will need to remove the pump from the spa to more easily make the repairs.


Once the spa pump is removed you need to open the back cover of the pump where the wires go and locate the pump shaft (some motors will just have a small round cap on the back, in the center of the motor remove this cap to expose the back of the shaft). You will need a good strong flat head screwdriver and vise grip pliers to hold the shaft still.

Power Flo pump

Once you located the shaft and know where you can grab it to hold the shaft still you need to remove the pump face plate, there are several small screws on the front of the pump, remove these and pry off the pump face plate and set to the side. Once open you will see the impeller inside the housing this is what turns to push the water through the pump, the seal assembly is located behind this impeller. 


Hold the shaft still and reach into the front of the pump and turn the impeller counter clockwise to unscrew the impeller off the pump shaft, this will expose the seal assembly. Seals have 2 parts to them as pictured above, the white ceramic seal and the spring type mechanical seal, when these two pieces get compressed they form a water tight seal between the plastic pump end and the metal motor end of the pump assembly.

Impeller front and
Picture courtesy of
Spa Parts Plus

You will see how these two seals are installed once you separate the impeller from the shaft, remove the old seals and REMEMBER which part of the seal goes where. The white ceramic part must come in contact with the raised part of the mechanical seal as pictured above. 


So once you removed the old seals and you are installing the new spring type mechanical seal be careful not to damage it, you may need a SMALL amount of lubricant to get the seal so slide into place be sure it is snug fitting, sometimes the mechanical spring seal is installed on the back side of the impeller and and the ceramic is pressed into the rear housing of the pump sometimes this is reversed, it is very important that you know what part goes where, take a picture once you have the pump apart you you can reference it later if needed.


Now you have the seals installed and it is time to re install the impeller and re install the front face plate of the pump. There is also an o-ring on the back of the face plate you may want to replace this as well. Once all this is done just re install the pump fill the spa and check for leaks. It sounds harder than it is. LOL just take your time and you will be fine.


Until Next Time...