Simon (Dark Angel) wrote:
On the water supply to my toilet cistern there's a 15mm ballofix type
isolating valve. One side is a 15mm compression fitting, which goes
onto the copper pipe. The other is a 1/2" female screw fitting, which
screws onto the threaded connection to the cistern ball valve, like
the one in this pic...

http://tinyurl.com/ya22ztv

Problem is its started leaking from 1/2" threaded end, where it
connects onto the ball valve fitting.

If thats plastic it highly likely its cross threaded

I replaced the fibre washer, it still leaks. Tried putting thread
tape around the threads on the ball valve fitting, it STILL leaks.

Also, it seems to leak worse when its done up tight than when its
slack.

All points to cross threading. When I fit new ball valves I hand tighten
the tap connector, then do up the nut that holds the ball valve into the
cistern.

Might have to replace it.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk