How to Fix a Leaky Faucet

Pry off the little hot or cold button on top of the handle with a flathead screwdriver. Underneath sits a brass screw - that's what holds the handle to the stem.

Switch to the right-size Phillips or flathead and press down hard before you turn. Brass is soft, and the head is sitting in a tight cone where one slip will round it off. Turn counterclockwise and back the screw all the way out.

Lift straight up. If you're lucky, the handle slides off the stem. More often, years of water have fused it on and it won't move.

Grab a faucet handle puller. Drop it down inside the handle, hook the bottom edge, and crank the puller's center bolt down against the top of the stem. The handle pops up off the stem without bending or breaking anything.

With the handle off, look at what controls the water. Modern faucets (last 20 years or so) use a cartridge - a self-contained plastic and rubber unit you yank out and replace whole. A few bucks at the hardware store and you're done.

Older faucets have a brass stem with a rubber washer pinned to the bottom. That's what this video is fixing. The washer presses against a seat to shut the water off, and replacing it is a 10-minute job.

Wrap an adjustable wrench around the hex packing nut at the base of the stem. Turn counterclockwise to break it loose. Once the nut is loose, you can usually unthread the rest of the stem by hand.

Lift the whole stem out of the faucet body. Flip it over and check the rubber washer at the bottom. If it's flattened, dented, cracked, or chewed up on one side, you found your leak.

The washer is held on by a single brass screw on the bottom of the stem. Press a Phillips driver firmly into the head and back it out slowly. This screw has been sitting in water its entire life, so the head is fragile - if you strip it, you're either drilling it out or buying a whole new faucet.

Pull off the worn washer, drop a same-size replacement on the post, and snug down a fresh brass screw. A new screw beats reusing the corroded one.

Look at the lip of brass that surrounds the washer. If the side is worn off or chewed up, water will blow past the new washer no matter how perfect it is.

The fix is to break the worn end off, grind the face flat on emery cloth, and add a retainer ring to hold the washer proud of the stem again. Now the washer has a flat metal shoulder behind it and can press cleanly against the seat below.

One last spot to check: the seat. That's the brass ring sitting at the bottom of the faucet body where the washer presses to shut off water. If it's pitted or cracked, even a perfect washer won't seal.

Drop a seat wrench down through the faucet body. The square or hex tip catches in the seat. Turn counterclockwise to back the seat out. If the seating surface is rough, swap it for a new one or smooth it on emery cloth. Two flat surfaces touching - that's the whole job. Reassemble in reverse, turn the water back on, and watch for drips.