This stop tap had been leaking a little bit for a very long time. Not enough for the customer to consider it an emergency. But enough for it to cause an unpleasant smell under the kitchen sink.

The customer was in the habit of turning their water off when they went on holiday. I think that’s a good habit to get into but this had worn the gland that seals the tap handle.
It’s possible to repair this by stuffing some PTFE tape into the gland. I never think of this as a long term measure so I always change the whole valve. You can find a stop tap on this link.
After turning the water off at the stop cock outside in the footpath I turned on the taps in the property to drain the pressure then turned them all off. This removes the pressure in the system but helps to hold the water in the pipes.

The tap was in a awkward position so I turned it off, loosened the bottom connection then put the whole tap in a bin liner with the valve still closed. When I opened the tap there was a gush of water but it was all safely contained in the bag rather than going under the kitchen units.

Once the water stops running it’s a simple job to remove then refit the stop tap. I always like to wrap a bit of PTFE tape around the olives for extra peace of mind.
Turn off the stop tap then turn on the external stop tap. Check for leaks, turn on the stop tap, check for leaks. Leave it for 5-10 minutes check for leaks.