3G-4C Cold Water Stem Ceramic Disc Quarter Turn Cartridge for Pfister

First, determine the source of the leak. If water is leaking from underneath the handle onto the counter, the stem of whichever handle is leaking needs to be replaced. If water is dripping from the faucet, turn off the hot water supply valve under the sink. If water is still dripping, you need to replace the cold stem (right handle). If the water stops dripping when you turned off the hot water valve, you need to replace the hot stem (left handle). Once you’ve determined the trouble stem, turn off the water supply.

Remove the Handle by lifting off the Index Cap with a flathead screwdriver. Next, Remove the handle (so the stem is visible) by loosening the Set Screw by the screw counter-clockwise. Set aside the Handle, Set Screw and Handle Button to reinstall at the end of the project.  

If you have a plastic stem, unscrew the top cap and pop out the stem. If you have a brass stem, remove the stem by using a wrench and rotating it counter clockwise until it threads out entirely. Take a look at the Washer which is located on the lower end of the Stem. If the Washer is squeezed flat or has a groove worn in it, a Washer Kit coupled with a new Faucet Seat will likely solve your problem. When replacing the faucet seat, you can remove and replace the seat with an Allen wrench or a seat removal tool. Turn the seat counterclockwise to loosen, clockwise to tighten. Once removed, you will need to take your stem to your local home improvement store and use the Perfect Match locator system from Danco or use the online Stem Finder. This system makes it easy to find your replacement.

Once you have purchased your new stem, you can install it into your faucet

• Install a brass stem by rotating clockwise until it threads entirely and tighten with a wrench.
• Install a plastic stem by placing the stem into the handle base and screw on the top cap.

Now is a great time to upgrade your faucet’s appearance with universal metal handles. How to install the new universal handles

• Place the handle adapter over the stem and tighten
• Place the new handle on the adapter and insert the handle screw into the washer then into the handle and tighten.
• If your new handle has an index button, place it on the handle.