Replacing the Mechanical Seal on Your Centrifugal Pump

It is I, Inspector Pumphead! I return this week to share some of the knowledge that’s inside my oddly shaped head, specifically the knowledge on how to replace the mechanical seal on your centrifugal pump.

The main purpose of the mechanical seal is to prevent leakage. They are a particularly important element of your pump because mechanical seal failure is responsible for a majority of pump malfunctions. By following these simple steps, you will be able to replace the mechanical seal in your pump so it experiences as little down time as possible.

-Armstrong 975000-982 Mechanical Seal Kit

The first step of replacing your seal, is to make sure the power to your pump is off because safety is always the first step. Next, disconnect the pump from the plumbing system by using a PVC saw. Place the pump on a table or spacious work area.

Using a wrench, unscrew the bolts on the pump housing. Detach the pump’s motor shaft from the housing. Make sure to keep track of the bolts you unscrew!

Dismantling the pump’s impeller is the next step, as the seal is located on the shaft behind the impeller. While holding the shaft in place, rotate the pump’s impeller counterclockwise with the wrench until it disconnects from the shaft. Part of the old mechanical seal will be attached to the impeller, while the other part will still be attached to the motor shaft. Remove both of these pieces.

-Goulds eHM Series Centrifugal Pumps

Now it’s time to put on the replacement seal. Slide the new mechanical seal along the shaft of the motor. Do not touch the front face of the seal, as it is highly sensitive to the oils on your fingers. Once the new seal is on the shaft, use the wrench once again to screw the impeller back on. After this, reattach the pump housing and motor by tightly screwing in the bolts.

Now that your pump is ready to go, the final step is placing the pump back into your plumbing system. You can do this by reconnecting the pump to the plumbing tubes with industrial strength PVC glue and primer. Wait a full day before starting the pump as the glue and primer need at least 24 hours to dry off.

So there you have it, in the matter of minutes your pump is back to new.  Be on the look out for another one of Inspector Pumphead’s Tips and How To’s, coming soon.

PumpProducts.com sales specialists are standing by to help you find the right pump or part, as well as to provide price quotes, stocking availability and shipping information. Call our toll free number 1-800-429-0800 to speak to an expert today.