I have a leaking water shutoff valve (pictured below). It appears to be a sweat shutoff valve that is soldered on to the pipe. It does not leak if I tightly shut off the valve, but any attempt to open the value causes leaking (admittedly I have to close it pretty tight to stop the leak).

Obviously I'd like to fix this through the easiest method possible. I could replace the entire valve, which would require either cutting the pipe or removing the soldering and pulling the valve off. However, there are valve stem repair kits that would involve just replacing the valve itself.

My main question is, is this a viable way to repair the leak? Given the fact that it doesn't leak when fully closed, does that imply a failure of a o-ring that such a repair kit would replace? Almost all advice I can find about replacing water shutoff vales involves replacing the entire valve, not just the stem.

enter image description here

1 Answer 1


Easiest fix - You have leaking packing (the seal around the valve stem) since it leaks only when open.

  1. Tighten the packing nut - hold the valve body still with one wrench so it does not try to twist the pipes while using another wrench to tighten the nut between the valve body and the valve handle (the "packing nut")
  2. If that does not fix it, shut off the water further back in your system and remove the packing nut (same process but loosen) - remove any old packing, apply new packing (hardware store plumbing section should stock it - teflon string, more or less, these days) then reassemble and tighten as in 1.
  3. You may need to take the valve stem out to repack. You can replace the sealing washer if needed which might make it easier to get shut off, depending on the condition of the sealing washer at present. This is rather less drastic than "a valve stem kit" that might or might not actually fit your particular valve.

If you do replace, get a 1/4 turn shutoff valve. They are far less prone to leaking or failing to operate after years of sitting open, as shutoff valves do.

  • 1
    +1 for the suggestion to go with a quarter turn ball valve.
    – Michael Karas
    May 21, 2020 at 4:16
  • Ditto that. Anytime I replace any valve I use a ball valve. And I actually hit the up arrow for a +1. May 21, 2020 at 12:10
  • 1
    Thanks for the advice. It turned out to be a slightly loose packing nut and all I had to do was make sure it was tight enough.
    – zephyr
    May 21, 2020 at 21:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.