A pump has two major sections: the wet end which holds the water and the motor which dives the pump's impeller to move the water. Generally these two sections are either bolted together (like most Hayward pumps) or clamped together (like most Sta-Rite pumps). This guide shows you how to replace the impeller in a pump that is clamped together. For instructions on changing an impeller in a pump that is bolted together, see our guide on "How To Replace A Pool Pump Impeller".
INTRO TO HOW AN IMPELLER WORKS - For a quick introduction, this picture shows the operation of the impeller. Water enters the center of the impeller. As the impeller is spun by the motor, a series of blades, like a fan, pushes the water to the outside edges of the impeller where it exits through slots to be collected by the diffuser. For an expanded explanation of how a pump operates click How A Pool Pump Works.
SECURE CLAMP - Make sure the Wet End and Motor are pushed together. Then slide the Clamp over the joint between the two and secure it by tightening the Clamp Knob. Turn clockwise. To make sure the Clamp seats properly, tap around it occasionally with a rubber mallet as you are tightening the knob.
CHECK FOR LEAKS - Check for leaks around all the O-rings and gaskets you changed in this procedure to make sure the connections are tight enough.