Step 1: Drain the skimmer and remove the pump.

Step 2: Remove the six nuts



Step 3: The end will come off



Step 4: Get a large flathead screwdriver. The shaft of the pump extends from inside the stock needlewheel all the way out the back side of the pump. Insert a screwdriver into the slot (which will hold the shaft in place), and unscrew the old needlewheel.



Step 5: If your new unit doesn't have the middle seal, move it to the new unit. This is one of the sealing mechanisms that allows the shaft to extend from the wet section here, through the air gap, and into the main pump. It is very important to be careful on removal (don't chip, exert excessive force, etc), as you can damage it. It comes out relatively easy with a larger pair of pliers and/or wrench. Wiggle it back and forth to remove it.



Step 6: Again use the screwdriver on the back of the pump, and screw on the new needlewheel. Get it tight, but not too tight. It should still spin a dozen or so rotations easy if you spin the unit by hand.

Step 7: Reassemble

Instructions courtesy of RS customer Eric Grotenhuis - Thank you!