Things You'll Need
Philips head screwdriver
A washerless bathtub faucet, sometimes called a cartridge faucet, is a faucet that doesn't use loose rubber washers to keep the seal watertight. Instead, washerless faucets use cartridges and tight O-rings to maintain the seal. You can easily repair a leaking washerless bathtub faucet even if you don't have any plumbing experience. You can find all of the parts you'll need at a hardware or plumbing supply store and have your bathtub faucet working properly in no time at all.
Turn off the water running to the bathtub faucet.
Pry the decorative cap on the top of the tap off the faucet. You can use a flathead screwdriver to get the cap off and expose the screw within.
Remove the handle screw from the middle of the faucet using a Philips head screwdriver. This is the vertical screw holding the handle to the rest of the faucet assembly. Pull the handle up until it comes loose from the faucet.
Take the cylindrical cartridge out of the faucet and pull off the spout. You should now be able to see the shaft sticking up out of the bathtub.
Cut off the O-rings around the metal shaft of the faucet using a utility knife. The O-rings are the rings on the shaft that are made of either rubber or a synthetic material.
Lubricate the new rings with plumber's grease and slide them onto the shaft. Position the rings in the same way as the old ones.
Slide the spout back onto the shaft and insert a new cartridge.
Put the handle back onto the shaft and secure it with the handle screw, then cover it with the decorative cap. The cap will snap into place when you press it down.
Bring your old cartridge and O-rings with you to the hardware store so you are sure to get the correct sizes.
Cut the O-rings down and away from you so you don’t hurt yourself because you will have to push the blade very hard to cut through them.