WC cistern flush seal

[cabman]

We have a problem in as much as the cistern flush pipes on both of our WCs don't always reseat  squarely after flushing, causing the cistern to run constantly.

The system involves a rubber seal landing on mouth of the flush tube.  Jiggling the pull handle stops the flow, but visitors are usually not so careful, and I remember that pre-wedding scene from the film Meet the Fokkers!

Does anyone know if this is this a fixable problem or another of those French plumbing funnies?

[Nick Trollope]

Go and get yourself a new chasse d'eau, and pay about 25E+. Cheap chasse (and cheap loos, with them fitted) are horribly unreliable.

Easy job & a great relief (ah ah aha) if you have a Saniflow or similar on yer loo.

 

[Babnik]

sounds like a "Griffon"...we've got one and have the same problems!! No known solution!

[Punch]

Before you  splash out 25 euros................Limescale is often the cause which obstructs the seal from sealing properly, you can also buy the replacement washers in most DIY outlets for a few centimes. I keep a small stock of different sizes in my van for my clients. Another thing to check is that nothing is obstructing the main central part of the mecanism dropping back down fully to make the seal after the flush. I recently found a plastic clip doing just that on a job.

However if the mecanism is old then a new "mécanisme de chasse" with dual flush 3/6 litres is what you need and  simple enough to replace.

Paul

 

[cabman]

Thank you for the replies.

This forum never fails!

It seems a cheap unit is currently fitted so replacement mecanism de chasse it is.

Just as a final bit of holding my hand, do I remove the cistern which is close-coupled with 2 bolts?

Also, if so, is it better to turn off mains supply and disconnect the UK-type tap connector, or does the ball valve come apart after turning off it's own isolation tap?

Any extra bits likely to be needed or pitfalls?

 

 

[Will]

This is a timely topic, as I changed one of these only yesterday, and if I can do it with my plumbing skills then anybody can.

A year or so back we had some plumbing work done, which included three loos (one new, two replacements for old-type ones which had a problem with the water not coming far enough up the S-bend, causing smells - another useful tip there I think). The guy could not get the loos we had chosen, so he installed cheaper ones, which he was very proud of - probably due to the reputation the British have, at least round here, for being cheapskates.

On two of those loos the flush mechanism has never worked properly, the guy adjusts it and it is OK, but back to its old ways after about ten minutes. Not wishing to carry on like that for ever, I have now replaced both of the mechanisms, and it's a pleasure to use the loos. In fact with the one I did yesterday I replaced the ball valve thingy as well, because that was leaking and causing water to constantly drain from the cistern into the loo (French ones do this rather than have a separate overflow pipe as seems to be normal in England).

Yes, you need to remove the cistern because the nut and seal thing holding in the new mechanism has to be really tight and you need to get to the bottom of the cistern in order to do this. As you say, just remove the two bolts holding the cistern to the pedestal. When you have undone the inlet pipe, the cistern should just lift off. You just have to shut off the tap on the inlet pipe - if you don't have one of these for any reason then you will need to shut off the main valve.

When you re-assemble it just make sure that all the seals are properly in place and everything is straight and level and done up really tight. The mechanism I replaced yesterday came with a plastic spanner, but this wasn't able to get the nuts tight enough without slipping so I had to use a wrench for that vital final fraction of a turn.