Hi all just thought I'd mention a possible failure mode & repair option for a dripping tap, which I'd not encountered before.
We have a Mixer tap in the kitchen sink with standard tap washers etc. Over the past few months it has started dripping, regardless of how tight you turned the handle. I first replaced the washer (or course), then tried a different (softer) washer, and then used a tap reseating tool to grind down the surface of the seat a little.
All of these worked for a while (a few hours or days) and then the problem started to return. I was close to taking extreme action - replacing the whole mixer tap, or gluing a new brass washer in place of the seat, when I had a different thought...
One think I noticed was that the tap became quite stiff when attempting to stop that ... final ... drop. I had assumed this was just the pressure of the washer against the seat. But in case this wasn't so, I decided to dismantle the tap valve itself. It was fairly easy to take apart and I then use a scotchbrite- type abrasive pad to clean a load of black gunk off various surfaces inside.
I reassembled it (using some Valseline as a lubricant) and refitted it, and bingo! Not only does the tap no longer drip, but the actual closing and opening action is vastly smoother.
I surmise that it wasn't the washer pressing against the seat that was stopping the tap turning, but the valve seizing against itself at a similar point. I thought I'd pass this on since tap valve failure seems to be rarely mentioned as a possible source of a dripping tap.
On a related note, how standard are such valves? This one is a 1/2" one with
20 splines for the tap handle. If I decided to replace it anyway, would I need to take it to a plumbers merchants for a match, or would those measurements do?Cheers jon N