How to Repair a Moen Kitchen Sink Diverter

Locate the two water shutoff valves under the kitchen sink, between the house water pipes and the faucet lines. Turn the handles of the shutoff valves clockwise to stop the water flow to the Moen faucet. Turn on the Moen faucet handle to release any remaining water in the line.

Remove the handle from the Moen faucet. Pull out the small rubber plug under the curve of the handle using a pair of needle-nose pliers to reveal the set screw. Remove the screw with a hex wrench and pull the faucet handle off the faucet.

Loosen the hex cartridge nut securing the faucet cartridge and spout with a pair of slip-joint pliers. Once loose, continue unthreading the nut with your fingers to remove it from the faucet.

Pull the cartridge straight up out of the cartridge sleeve, if you have a narrow ceramic disc cartridge. If your cartridge is the long standard Moen cartridge, remove the C-clip securing the cartridge to the sleeve with the needle-nose pliers. Pull the cartridge out of the sleeve.

Grab the neck of the Moen faucet spout close to the base. Lift up to remove the spout from the cartridge sleeve. There are two O-rings on the sleeve with a small circular piece between the O-rings. The small circular piece is the diverter.

Place the flat-head screwdriver behind the diverter, inside the cartridge sleeve and push the blade of the screwdriver to pry the diverter out of the sleeve.

Take the diverter to another sink. Run warm water and brush the diverter vigorously with an old toothbrush. This often is enough to loosen and remove any sediment preventing the diverter from operating correctly. If the diverter will not come clean or has signs of damge, replace it with a new one.

Insert the back of the diverter through the front of the cartridge sleeve. The front of the diverter has a small ring with a small gasket. Push the diverter into the cartridge sleeve until you feel it lock. The diverter should be flush with the outside of the cartridge sleeve.

Reinstall the cartridge into the faucet sleeve. If you have the long cartridge, push the C-clip back through the grooves on the cartridge sleeve and into the notches on the cartridge. Push the base of the spout over the cartridge sleeve until the top is flush with the top of the sleeve.

Thread the retaining nut over the cartridge and spout base until it is hand tight. Place the handle back on top of the nut and secure it with the retaining screw. Push the rubber plug over the screw head. Turn on the water supply to the Moen faucet.