Cistern fill valve replacement

Sep 30, 2013 2 Replies

The flush mechanism on our close coupled WC has begun to fail so I set abou t replacing it, as I have done in another WC in the house, with one of the Fluidmaster button press devices. Not making the same mistakes as last tim e, I ensured I had a close coupling bracket / donut available, and also dec ided to replace the fill valve too as the old one had had a few wobbles rec ently.



When taking off the cistern I had a bugger of a time getting the inbound wa ter supply disconnected from the fill valve in the cistern as the water-sid e threaded connector was almost impossible to reach, but in the end I manag ed to get it out by unscrewing the part inside the cistern, which was very effective.



In reverse, this is causing me some problems. I seem to have managed to ge t the threaded connection to the water supply "dry" through lots of small m ovements and fiddly twisting.



But the seal on the cistern side of things is persistently dripping a small amount.



The instructions tell me not to tighten the back nut more than 1/4 beyond h and tight, but that feels too loose, and definitely drips. I've then progr essively tightened it up, but there's still a small drip. Should I just co ntinue with tightening, or is this likely to be a case of reversing everyth ing I have done, remove the cistern again and re-seat the rubber seal insid e the cistern?



Matt


I 'always' spread LS-X around the tapered rubber washer inside the cistern. You only need a slight imperfection in the cistern material to cause a drip.

Cheers, sounds like that's a sensible enough option. The fitting is a real bugger to get at, the pan has a very un-generously sized access hole throu gh which to reach both the connection to the fill valve and the back-nut, s o in reality the only way to access the back-nut is to raise the cistern sl ightly from the pan. I blame the previous owners for buying a "nice" looki ng toilet!

Matt

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required