On 20/08/2018 11:43, Brian Gaff wrote:
Mine is, but the real issue last time was the scale build up in the valve
causing it to not close correctly and leak.
Brian

You can dig it out with a sharp instrument and then cut a
standard tap washer down to size and force that in.

However a complete new ball valve/float assembly is only about a
tenner, so you could just replace the entire slider and outer
enclosure since the threads will be standard.