My pump is leaking .What causes that and how do I fix it

Thank youfor posting your question here on Fixya.com. The leak is likely caused by a defective pump seal. If you look at the parts breakdown at http://www.star-pool.com/assets/Hayward-Pool/Hayward-Manuals/Hayward-SP2610X15-Super-Pump-Parts-Diagram.pdf you can see the seal and the other parts that must be separated in order to replace the seal.

THE HARD WAY! Once you are sure the seal is defective you need to buy a new one along with a diffuser gasket, a pump housing gasket and some pump gasket grease.

The 4 housing cap screws and the impeller must be removed in order to remove the 4 motor cap screws. The hardest part of this process is removing the impeller. The cover on the other end of the motor should be removed and the motor shaft held with a wrench. The impeller must then be removed by turning it with a large pump pliers or by inserting a screw driver into one of the holes on the outer edge of the impeller in order to turn it counterclockwise with the shaft held with the wrench. If this damages the impeller it should be replaced.

Now remove the 4 motor cap screws and everything is apart except the seal. Half of the seal can be removed from the motor shaft and the other half from the seal plate. Placing a socket on the back side of the seal that is on the seal plate allows the seal to be removed by tapping it with a heavier tool (hammer or pump pliers). Clean this area, apply a little silicon adhesive to the area and insert the new seal half into the seal plate using the instructions that are included with the seal.

Use pump gasket grease on the pump impeller gasket and reassemble the completely reassemble the pump.
THE EASY WAY!
Remove the piping from the motor and the electrical conduit and wires from the end of the motor. Bring the pump to Leslies pool supplies (I don't work there or own any of their stock) . If they are not very busy then they will do the above and only charge you for the parts while you wait.

I have replaced so many seals I almost always do it myself at the pool site but it is not easy for the first timer.

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