How to Take Apart, Inspect, Repair and Reassemble a Leaky Bathroom Faucet

Take Apart the Faucet

1). Turn off the water to the faucet. Usually there is a supply valve below the sink or behind the faucet. If you cannot find it, or cannot reach it easily, turn off the water supply to the house. Determine which kind of faucet you have. Washerless faucets vary in design, but they come apart in the same way as compression faucets. Work your way down to the washer or cartridge that is leaking.
2). Pry the decorative cap from the handle, using a thin knife blade. Avoid scratching the faucet. Remove the screw beneath the cover and the handle.
3). Loosen the bonnet nut with an adjustable wrench or a plumbers wrench. Unscrew the nut and the valve stem below it.
4). Remove the screw on the bottom of the valve stem that holds the washer in place. On a washerless faucet, remove the nut and clip holding the valve cartridge in place.

1). Inspect the valve stem and faucet for signs of mineral deposits or wear. Clean the parts thoroughly, scrubbing with a small brush.
2). Replace parts that are pitted, eroded or that will not come clean. Replace the entire cartridge on a washerless faucet.
3). Replace the washer with an exact duplicate. Take the washer to the store with you to make sure you get the right washer. Replace the screw holding the washer in place.

1). Place the valve stem back into place, making sure the spring is still in position below it.
2). Replace the bonnet nut and tighten it.
3). Put the handle back on and screw it into place. Pop the decorative cover back into place, pushing to seat it firmly on the handle.
4). Turn the water back on and confirm that your faucet is free of leaks.