Faulty Cistern.

[gazzafield]

My toilet cistern fairly recently started getting quite annoying. You go to flush and the handle just goes down but not a lot happens flushing wise. You have to "pump" the handle half way down and slowly two or three times and then it will flush.

I had to replace the tie rod from the handle to the plunger a few years back as it rusted through and I wonder if this might be relevant to my current problem. Getting in to the cistern workings is a PITA as it has been boxed in and is only accessible through a small hatch at the top about 15 inches wide and four inches deep. This has put me off looking again. Any ideas?

[Andy Cap]

If it's the old type, it sound like the diaphragm has failed. They used to be rubber but are now plastic. I used a couple together a few years back or you could cut one from a sheet of stout pastic. There's no easy way of doing it !

ANdy

[Si]

In message , gazzafield writes

The syphon diaphragm has failed. Either change that or for not much more money change the complete syphon.

[Stuart Noble]

A quick job. Spend the rest of the weekend re-doing the boxing-in. Think yourself lucky it hasn't been tiled....:-)

[Lobster]

It won't cost a penny to fit a new diaphragm though, if you use a bit of spare plastic! Not much point buying one from B&Q for a quid, as IME they always need trimming to fot anyway.

To the OP - yes, sure to be the diaphragm: I'm afraid there's nothing for it but to remove the syphon, for which you'll need to access the underside of the cistern to release the retaining nut.

So a cheap job but time-consuming for you... maybe you can take the opportunity to rebuild the boxing with a bigger access hatch!

David

[TheScullster]

"Lobster" wrote

Also consider fitting a 2 part syphon which allows the diaphragm to be changed without removing the whole unit. And incorporating a removable panel in your box work for access.

Phil

[Mike Scott]

Lobster wrote: ...

Daft question, but - having similar symptoms - I see I can't get at the underside of the cistern, as it's a low-level cistern fitted flush to the back of the pan. The cistern is held to the pan with two large bolts and wing nuts, and lots of mastic. I've looked inside, and there's no obvious fixing either. So how should it come apart........??

[gazzafield]

[Si]

Buy replacement syphon kit which will probably have diagram showing how it all goes together. Turn off water supply or tie up valve. Flush loo to empty cistern.

Remove as much bodger's mastic as possible. Undo wing nuts. Undo screws which hold cistern to wall. Lift cistern off.

You will now have access to large plastic nut which unscrews from the bottom of the cistern.

When replacing syphon ensure you fit the doughnut washer the correct way up. (I didn't once and it leaked until I repeated the process correctly.)

[Appin]

The message from gazzafield contains these words:

What sort of cistern is it? Sounds like a split diaphragm if it's a siphonic cistern. If so, replace the siphon -- cost is negligible. Or if you're really mean, cut a new diaphragm from any convenient material, ideally neoprene.

[Stuart B]

You have answered your own question ."The cistern is held to the pan with two large bolts and wing nuts "

Cut of the water supply to the toilet,detach the overflow pipe if fitted ,unscrew the wing nuts and remove any screws holding the cistern to the wall. Lift off the cistern and empty it somewhere ( bath?) .Remove the fittings on the bottom of the cistern and then remove the large plastic nut etc .This will free the syphon but you need to detach the link to the flush handle . Replace the cistern ..a new one might have a built in overflow so that will make any existing overflow redundant so you might wish to block off the top of the overflow pipe but it's probably not necessary Refit in reverse of above .

[Lobster]

Yep - if there's loads of mastic it may be well stuck down and take some shifting... try to get a stanley blade or something between them surfaces to cut through as much as possible!

David

[Mike Scott]

possible w/o removing the entire cistern. Oh well, live & learn :-(

Looking in the screwfix catalogue, I see there's a 'flapper valve' listed as an alternative to the syphon (p/n 36240). Is it worth paying extra for one of these?

[Si]

I'll confess that I have never actually removed the cistern from the wall when replacing the syphon but I thought it best to tell you how to do the job 'properly'.

The first time I had to do the job I didn't take advice and made the procedure up as I went along. I decided that removing and rehanging the cistern (and disconnecting and reconnecting the overflow pipe) was too much hassle and, having emptied the cistern as much as possible and having undone the wing nuts and removed the bolts I managed to tilt and manoeuvre the bowl out from its connection with the cistern and waste pipe in the wall. (At this point you need a low profile bowl to catch water that comes out the back of the U-bend.) Having replaced the syphon I then succeeded in refitting the whole caboodle. (Note I've done this twice as first time I stupidly fitted the doughnut washer upside down so that it leaked.)

I'm sure someone will be along in a mo to tell you why doing it my way is crazy but it did enable to realise that emptying the waste water from the carpet shampooer down the loo was a bad idea as grit was collecting in the folds of the rubberised waste pipe connector.

[Appin]

The message from Mike Scott contains these words:

IMHO NO, NO, NO and NO again!

In general use in the USA and certainly all the ones I've seen there have been an unmitigated disaster.!

[<me9]

Not unless you want to repeat the job every couple of years. they leak after not too long. A syphon rarely, if at all leaks, and will probably do 20+ years.

[Mike Scott]

Hmmph. More like 10 for the present one. But I'll take the advice and stick with a new syphon.

Thanks all.

[Stuart B]

Yes.Doing it that way IS crazy ..