Why Your Faucet Keeps Dripping After You 'Fixed' It

You did the work. You shut off the water, found the little screw under the handle cap, pulled the stem, and there it was — a flattened, cracked rubber washer that looked exactly as guilty as everyone said it would. You put in a new one, put everything back together, turned the water back on feeling pretty proud of yourself. Two weeks later, the same faucet is dripping again, maybe from the same spot, maybe from somewhere new. This is one of the most common repeat calls in plumbing, and it happens because a dripping faucet almost never has just one point of failure — the washer is just the part you can see first.

Most faucets built in the last twenty-five years aren't the old compression-stem type with a single rubber washer at all. They're cartridge, ball, or ceramic-disc faucets, and each of those has its own set of wear parts that a washer swap doesn't touch. If you replaced a washer and the faucet is still dripping, there's a good chance you fixed a symptom and left the actual cause in place.

The parts nobody thinks to check

Inside a cartridge faucet, the washer sits at the bottom of a plastic or brass cartridge, but that cartridge also has small rubber O-rings sealing it against the faucet body, and a seat — a small ring, sometimes rubber, sometimes a metal insert — where the cartridge meets the water supply. Any one of those can wear out independently of the washer. A worn valve seat will let water seep past even with a brand-new washer sitting right on top of it, because the seat itself is pitted or no longer sealing evenly. O-rings dry out and lose their shape from age and hard water, same as any rubber part exposed to minerals for a decade.

Ball-type faucets — common on some single-handle kitchen models — have a whole small parts kit: springs, seats, and a rotating ball with O-rings, all of which move against each other every time you use the faucet. Replace only the seats and springs while leaving a scored, worn ball in place, and you'll be back here in a month.

Ceramic-disc faucets are different again. They use two hard discs that slide against each other to control flow, and instead of wearing out from friction the way rubber does, they usually fail because sediment or mineral grit gets between the discs and keeps them from seating flush. A cloudy, grit-covered disc can look almost fine and still leak steadily.

Why matching the exact part matters more than people expect

Here's where a lot of well-intentioned repairs go sideways: faucet cartridges and stems are not universal. They're specific to the manufacturer and often to a particular product line and vintage, down to the housing shape, the spline pattern that locks into the handle, and the exact seat depth. A washer that's a hair too thick or too thin, or a cartridge that's a close-but-not-exact match, can seal well enough to pass a quick test at the sink and still weep under real water pressure once you walk away. Bring the old part with you to the hardware store, or better, snap a photo of any stamped model number on the faucet body or under the handle before you buy anything. If you can't find a stamp, the faucet's general shape and the handle style will usually get a knowledgeable counter person to the right family of part.

It's also worth checking whether the drip is even coming from where you think. A drip at the spout with the faucet fully off points to the cartridge or stem assembly. A drip or dampness around the base of the handle, or water pooling under the sink at the supply connections, points somewhere else entirely — and no amount of cartridge work will fix a loose supply line nut or a bad connection.

When it's time to stop chasing parts

If you've now replaced the washer, checked or replaced the O-rings, and the faucet is still dripping, the honest move is to replace the whole cartridge or stem assembly as one unit rather than keep swapping individual pieces. Manufacturers sell the full cartridge specifically because it's easier to get a clean seal on a fresh, matched assembly than to chase down which of five small rubber parts inside an old one has finally given up. It's usually not much more expensive than buying the pieces separately, and it saves you a second trip.

A cartridge swap is a genuinely approachable DIY job on most single-handle faucets: shut off the supply valves under the sink (test that the water is actually off at the spout before you start), pull the handle, remove the retaining clip or nut holding the cartridge, and the old cartridge usually pulls straight out. The trick is orientation — note exactly how the old cartridge is seated, because installing a replacement rotated even slightly will mean hot and cold are reversed, or the handle won't sit right.

The three-strike rule

A good rule of thumb: if a faucet drips again within a few weeks of a repair, that's not bad luck, it's information. One repair attempt that fails usually means a missed part, not a defective new washer. Two failed attempts on the same faucet usually means it's time for the full cartridge or stem, not another trip for a smaller piece. And if a faucet is old enough that replacement cartridges are hard to find for it, sometimes the more honest answer is that the faucet itself, not just its innards, has reached the end of its useful life. That's not a failure on your part — hardware wears out, and knowing when to stop patching and start replacing is its own kind of competence.