Things You'll Need
Deep-socket faucet wrench
Faucet washers or replacement cartridge
If you're having problems with a leaky bathtub or shower faucet, it can be easy to fix yourself if you know the procedure. Fixing the leak yourself can save you from an expensive plumbing bill, and only takes a few tools a parts from your local plumbing store. Bathtub and shower faucets can have two handles, one for hot and one for cold, or a single handle to control temperature. The replacement parts depend on your faucet type. Two-handle faucets will usually just need washer replacements, while a single-handle faucet will need a new cartridge.
Repairing a Recessed Two-Handle Faucet
Turn off the water supply. Remove the faucet handle index covers (the plate or cover in the center of the handle). Use a utility knife or a screwdriver to pry the plate away. Remove the handle screw with the appropriate tool for the screw. You may need to use needle-nose pliers or an adjustable wrench to remove the screw or nut. If there is no nut or screw, the faucet (escutcheon) is attached to the faucet stem, and you must unscrew the assembly away from the wall. Grip the escutcheon with your hand and unscrew it, using a counterclockwise motion. If it will not loosen by hand, use smooth-jaw pliers or a strap wrench. Do not use a tool that will damage the metal or chrome. If the escutcheon is caulked on, use the utility knife to cut through the caulk.
Reach the recessed bonnet nut, using a deep-socket wrench. Remove the nut and stem from the faucet body. Replace the washer by unscrewing the seat.
Reassemble the faucet, starting with the nut and stem, using the deep-socket wrench. Turn the water back on and test the faucet.
Single-Handle Bathtub/Shower Faucet
Turn off the water supply. Remove the insert from the plastic handle with a utility knife or screwdriver. Use a Phillips head screwdriver to unscrew the handle screw. If your model has a cam fitting or bushing, remove it.
Remove the metal sleeve from the cartridge and column. Remove the U-shaped retaining clip from the column, using needle-nose pliers.
Pull the cartridge away from the column. Replace it with a matching new one. It is best to replace all worn parts, including the retaining clip, metal sleeve and the handle. Reassemble the faucet by reinserting the retaining clip, replacing the metal sleeve to the column, and reattaching the handle. Turn the water back on and test the faucet.
Use a bowl to hold screws and other small parts during the repairs so they don't get lost.
Use a washcloth or rag to wrap around chrome fixtures to protect them from tools with teeth.