To fix a leaky bathroom faucet, prepare the sink and your tools, and take the fixture apart. Replace the seat washer and the O-ring, apply plumber's grease, and re-assemble the faucet.
- Prepare the sink
Shut off the water, and close the sink drain.
- Prepare your tools
Apply duct tape to the jaws of your wrench to prevent the tool from scratching the fixture. Dip a soft scouring pad in vinegar, and use it to clean mineral deposits.
- Take apart the faucet
Use a screwdriver to gently pry off the decorative cap on the handle. Remove the handle screw, and pull the handle off.
- Remove the faucet handle
Unscrew the packing nut with a crescent wrench, and unscrew the stem.
- Replace the seat washer
Use a screwdriver to remove the brass screw holding the seat washer in place. Remove the seat washer. Place a new seat washer in place, screw it back in, and coat the washer with heat-proof plumber's grease.
- Replace the handle O-ring
Pull the stem out of the packing nut. Replace the O-ring with a new one that matches the size exactly. Coat with plumber's grease.
- Re-assemble the faucet handle
Place the stem back inside the packing nut. Screw the packing nut back into the handle, making sure it's tight. Use the handle screw to finish assembly. Ensure the faucet is no longer leaking before popping the decorative cap back into place.