Take the back housing off the pool pump motor by unscrewing the small screws.
Reach into the back of the motor to locate the nut holding the impeller screw in place. Navigate the area carefully so you don’t accidentally disconnect any wires.
Hold the nut in place with the pliers and unscrew the impeller. Depending on how long the impeller has been in place, it may take a bit of pressure to remove the screw while holding the nut in place. Once you remove the screw, you can remove the impeller.