- 1). Close the water supply that feeds the faucet. Look under the sink for two small valves. Turn the valve handles to the right as far as they will go. Open both faucet handles to insure the water flow has stopped. If you do not have any fixture shut-off valves, you will need to turn off the main water supply in the basement or out by the street at your water meter.
- 2). Remove the faucet's handles with a screwdriver or Allen wrench. You may need to remove an index button from the top or side of the faucet handle with a flat tip screwdriver in order to access the handle retaining screw. Rotate the screw to the left, or counterclockwise, to loosen and remove the handle.
- 3). Unscrew the faucet's washerless cartridge retaining nut or bonnet nut. Turn the nut to the left, or counterclockwise, to remove it. In most cases, you can loosen the nut with an adjustable wrench or slip-joint pump pliers and then finish removing the nut by hand. If the nuts are difficult to remove due to corrosion or mineral buildup, soak them with a washcloth dipped in white vinegar.
- 4). Pull the cartridge out of the faucet body by hand or with pliers. Inspect the inside of the faucet body for mineral buildup. If there is buildup, sand it until it is smooth with a small piece of plumber's emery cloth. Wipe any remaining debris out of the cartridge barrel with a clean, dry cloth.
- 5). Install the washerless faucet cartridge by hand. Screw the retaining nut back on by hand, and then secure it with an adjustable wrench or pliers. Reinstall the faucet handles, handle retaining screws and index buttons. Turn the water back on and test the faucet for leaks by operating it several times.
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