I want to change the faucet on my vanity, so I was cutting the water off at the valves under the sink (image below) - cold works fine, but the hot, even when the valve is as tight as I can get it there is a slow slow steady drip.

What must I do so that when I turn this valve to the off position no water continues to drip?

Under-sink stop tap

  • Probably replace or clean the valve(if in hard water area). Might be able to repair it.
    – crip659
    Commented Mar 15, 2022 at 17:56
  • @crip659 - not in hard water area. The only nut I see to unscrew is the one in the image. Is there one on the bottom side that is not included in the image? Commented Mar 15, 2022 at 18:00

2 Answers 2


The hot valve may be defective, or the rubber washer inside may just need replacement.

Shut off the main water supply to your house and rebuild or replace the valve.

For replacement: It's easier to replace than you might expect. Use a pair of wrenches, one to hold the pipe in place while you unscrew the valve. Apply force in opposite directions on the wrenches. I recommend placing a piece of rubber between the wrench and the pipe so you don't scratch it up. The valve should have a hexagonal "nut" welded to its body that you can grip the second wrench onto. Loosen counter-clockwise and the valve comes right off. Clean off the pipe threads, wrap with a few turns of teflon tape, and screw the new valve on. Use two pliers in opposite directions similar to what you did to loosen it.

  • i just removed a working valve from a different sink yesterday, could I replace it with that one, or should I get a new one? I'm out in the country so closest box store is about 70 miles from me :D Commented Mar 15, 2022 at 17:59
  • It is usually recommended to replace with new, but a known good valve will work as well, if same sizes for attachments.
    – crip659
    Commented Mar 15, 2022 at 18:33
  • It's up to you what you replace it with. The used one will do in a pinch, just know that it probably has less service life remaining than a new one. Pick up a spare next time you're at a hardware store.
    – pmont
    Commented Mar 16, 2022 at 4:08

Your hot shut off valve seems to be a multi-turn valve, which would have an internal rubber washer on the end of the shaft to fully seal the opening when the valve is shut off. Especially on a hot water line, this rubber washer degrades over time and no longer fully seals when the valve is off.

Side view of typical multi turn shutoff valve: enter image description here

Fortunately, it's pretty easy to replace the washer (and the washer sealing around the shaft where it exits to meet the handle) without removing the valve. Just shut off water upstream, release pressure, and carefully undo the packing nut (the nut just under the handle) to remove the whole shaft assembly. Either replace the two washers or the whole shaft and reassemble, adjusting the packing nut tightness to prevent leaking around the shaft. Here's a photo of a typical replacement kit: enter image description here

You're looking for an "angle stop rebuild kit". I would purchase one with a proper brass metal shaft rather than the plastic one in the photo. Any plumbing supply shop online or brick n mortar should be able to get you the right kit.

Ask This Old House has a YouTube video that shows how to do the rebuild.

  • 1
    the issue is behind the handle and not the bolt that is on the top (from the side view image you posted)? Commented Mar 16, 2022 at 17:21
  • Yes, I edited photo and added link to rebuild video
    – Armand
    Commented Mar 16, 2022 at 19:03

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