Removing an impeller and replacing a shaft seal
Water Leaks at the Pump Motor Shaft

STEP 1) What’s causing this leak is a mechanical shaft seal that has failed due to water/chemical corrosion, or the pump/motor running dry. Following the instructions below should guide you through a successful shaft seal replacement.

There are a variety of different shaft seals for pumps; you will find all of them in the "Pump Parts" section of our catalog.

STEP 2) You must first remove the pump cover that is usually held on by screws or a stainless steel band. After removing the pump cover you will see the impeller, this will have to come off to get to the seal following these instructions.

STEP 3) The impeller screws on to the motor shaft with regular threads, to remove it the motor shaft will have to be held in place while unscrewing the impeller (counter clockwise). On the back end of the motor (where electrical cord is) you will find a place to hold the shaft, either behind a metal knock out, or by removing the end cover. In most cases after doing this, you will notice a place to put either a flat blade screwdriver, or 7/16 open-end wrench to hold the shaft in place. In other cases, it can be held behind the spring action mechanism, where you will find that the shaft has two smooth sides where a 7/16 open-end wrench can be used to hold it in place.

You are now ready to unscrew the impeller (counter clockwise). Sometimes it helps to have two people doing this, one to hold the motor shaft while the other unscrews the impeller. You may have to use a pair of channel locks to help unscrew the impeller, (be careful they break easily) but don’t get frustrated if it does, it happens to the best of us. If this does happen you can find all the impellers in the pump parts section of our catalog. After removing the impeller you will want to remove the seal plate housing that is attached to the motor by four bolts that run the full length of the motor. You will find the head of the bolts in back of the motor, where the electrical is supplied. It will take a ¼" nut driver to do this. After it has become detached, you are ready to replace the seal following the instructions below.

STEP 4) NOTE: If while replacing the seal you see a clear plastic cup w/O-ring, (pictured below) then it also will need to be replaced. This usually applies with the 200 series or the 4702 series seal; these are one in the same. *Not all pumps have the clear plastic cups.

While removing it make sure you remove and discard the old O-ring. When looking at the new clear plastic cup you will notice a groove on one side, this is where the O-ring will go. Before reinstalling it, put 100% silicone on the O-ring and then press it firmly back into the place you took the old one from. Proceed with the instructions provided with the seal kit.

ONE MORE NOTE: If the seal you are replacing is the 1000 series series, then it is recommended you put 100% silicone on the back side of the stainless steel cup before installing it. Make sure that when you do install it, it goes all the way in. A "bottoming out" feel. We use a 1" PVC coupling to "knock" it in.

When reinstalling the impeller, the shaft will need to be held again while you hand tighten the impeller. Make sure that any build up on the motor shaft has been cleaned up, or the impeller "tube" will break.

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