Shut off water supply valves, then drain the lines by turning both faucet handles on.
Pry off decorative cap on handle and remove the screw holding the handle.
Gently pry off handle with a screwdriver or use a faucet handle puller.
Use pliers or wrench to remove stem locknut/bonnet.
Depending on style of faucet, either unscrew stem or lift up to remove stem cartridge from faucet body.
To replace stem washer, remove brass screw (Fig. 3) and replace washer.
To resurface a worn or pitted faucet seat, insert faucet reseating tool as shown in (Fig.4). Press lightly and turn handle clockwise several times. Check for smoothness and be sure to remove filings with damp cloth.
To remove an old seat, use faucet wrench (Fig. 5) and turn counter-clockwise, then lift it out. When installing a new seat, use pipe joint compound on outside threads of the seat to ensure a good seal.
Leaks at the faucet handle can usually be stopped by replacing the packing washer (Fig. 6). If you do not have or cannot get the correct washer, string packing (Fig. 7) can be wound clockwise around the stem using 1-1/2 times as much thickness as would be required to fill the packing nut. When the nut is tightened, the packing compresses into solid form and acts as a seal.
Newer cartridge stems simply require the replacement of “O” rings to eliminate leaks.