desildu
You don't say what car this cistern is fitted to - but the plastic diaphragm has split in the flush mechanism. Remove the handle link and the outlet pipe/securing nut and lift out the whole flushing unit.
Once lifted you'll see the clear plastic diaphragm above the wheel-spoked plunger and you can either get a new one from any plumbers' merchant or cut one out of a strong piece of polythene. The last time I did one I used a bit cut from a Ford bumper wrapper. Ten years on - still going!
[Yes; I know! The Curse of Murray Walker....]
|
Yes it is the plastic diaphragm that has failed.
There were about 10 different shapes and sizes of them when I went to get one a couple of months ago. cost not more than 50p.
Getting access to the plunger may not be as simple as Screwloose suggests.
If the cistern is close coupled i.e. bolted to the pan then it needs to be unbolted and lifted in order to get to the big nut underneath. If the water feed pipe is vertical either to the top or underneath of the cistern then this will probably need disconnecting and possibly also the overflow pipe.
I would always replace the big fat spongy doughnut washer and possibly the other rubber sealing washers while doing the job.
The last diaphragm I replaced on an old cistern also required a new clamping plate, after I had sawn it off, to fit under the cistern.
It all depends on your DIY ability. Not a difficult job but be prepared to dismantle pipe joints after turning the water supply off.
Very, very unlikely but if you have a rare "double trap close coupled siphonic suite" like I have then do not attempt it unless you fully understand things. They need very careful re-installation or they will not work.
I had to effect a very involved copper spliced repair to the the very special plastic tube inside the siphon as spares are not available.
|
>>"double trap close coupled siphonic suite"...
I'm intrigued. What are the advantages of one of these cisterns?
Happy Flushing Phil I
|
>>"double trap close coupled siphonic suite"... I'm intrigued. What are the advantages of one of these cisterns?
They forcefully suck out the contents.
The pan, tank and siphon are all different to the normal.
Normal toilets are washdown.
www.bathroomobsoletes.co.uk/B1.htm
The cross section shows the complexity of the double trap pan.
It does not show the "simpler" single trap siphonic pan.
The siphon is different, it has an special shaped air tube that extends through seals into the back of the pan.
|
Best to fit a complete new detachable syphon.
It amazes me how in the UK some aspects of plumbing have become over engineered. The french loos just have a plunger you raise, you can release just the quantity of water you want depending on the contents of the pan. I guess that's what 30 years of water metering does to the design. And why bother with a separate overflow? Just send it down the pan.
|
Best to fit a complete new detachable syphon.
I cannot agree with that. There are many types and sizes.
It amazes me how in the UK some aspects of plumbing have become over engineered. The french loos just have a plunger you raise, you can release just the quantity of water you want depending on the contents of the pan. I guess that's what 30 years of water metering does to the design.
We do of course have a limit on cistern size and dual flush - half or full cistern discharge.
>>Why bother with a separate overflow? Just send it down the pan.
The objective is to have an obvious indication of the valve failure. It is fail safe.
Overflow discharge can now be into the soil pipe via a simple non return valve or I understand into the pan.
If the pan blocks AND the overflow happens then get paddling.
|
If the cistern has to come off then for a modest £6 more then I would fit a detachable syphon www.andyplumb.co.uk/product_subcat.asp?typeID=1014...7
At least when the job needs doing next time it's a five minute job rather than having to take the cistern off again. If it's a rented house or you may move in the next few years then perhaps don't bother.
|
If the cistern has to come off then for a modest £6 more then I would fit a detachable syphon www.andyplumb.co.uk/product_subcat.asp?typeID=1014...7
>>
or even £3.50 plus vat from Screwfix
Even your link shows more than one siphon.
Stick with the existing one. Only the plastic diaphram fails.
It is only one small nut to be removed. At least when the job needs doing next time it's a five minute job rather than having to take the cistern off again.
???
I am not aware of a standard type siphon that is removable from inside the cistern.
In the illustrations the black washer fits inside the cistern and just underneath you can see the large nut that goes outside the cistern.
www.buildingforafuture.co.uk/autumn02/focus_on_wat...p
Lots of info plus it shows a siphon , the French job and another type.
All require a fixing nut under the cistern.
www.solutionelements.co.uk/Downloads%20copy/ WCstate%20of%20the%20art.pdf
Covers the subject in depth.
" Unlike the humble siphon, which is hydraulically sophisticated but mechanically simple, the drop valve is hydraulically simple (a plug in a hole) but often mechanically complex.
|
I think we may be talking at cross purposes. You are correct that there is no syphon that is completely detachable from inside the cistern - not to my knowledge anyway. However, there are syphons on the market now (the second one in my link called 'Metro') where you can disconnect the part of the syphon containing the plastic diaphram. In the picture this is done by the blue collar on the left. Therefore my view was that if the cistern has got to come off anyway, I would spend the money to put one of these detachable syphons in so that if the diaphram goes in the future, the cistern does not need to be removed and the entire job can be done in five minutes.
When replacing the diaphram I use a piece of DPM, seems to last much longer.
|
I think we may be talking at cross purposes.
All sorted. Thanks for the clarification.
I was not aware of that type of siphon unit that can be separated to leave the outlet pipe in situ.
Such a simple idea.
|
|
|
|
>>It amazes me how in the UK some aspects of plumbing have become over engineered.
Not at all. For very good reasons.
>just have a plunger you raise, you can release just the quantity of water
Yes. And when the washer goes on the bottom of the plunger, you end up with a leak; wasting water. Up until very recently, British Building Regs did not permit this sort of system - on the grounds that the water wasted through failure of the washer would be enormous.
>And why bother with a separate overflow? Just send it down the pan.
Because again the design is cleverer than that. When you have a leak, you need to be forced to fix it. So if the water is splashing on your shoes when you go out of the front door, you will have it fixed promptly. Let the overflow down the loo & it might be months before you notice it, let alone fix it.
|
I'm told by my SIL a Plumber that the common belief as to why plastic diaphragm fails is because of these hang inside the cistern blue sachet thingies.
Never heard of this before but it sounds feasible.
|
I have had them fail and never used a "hang in the cistern blue sachet thingy"
Female plumber? dont trust em........
------------------------------
TourVanMan TM < Ex RF >
|
Sexist.......Actually its a he and not a she.
Now I have in my old fittings cabinet the ultimate in diaphragms for cisterns. Its in solid gunmetal brass apart from the actual disk which is copper. This copper disk slides down the shaft after the flush allowing the lever to return.
British crafmanship lost for ever to the plastic brigade.
|
|
|
|
|
Thanks for that link Henry. Will be a really useful source to match bathroom fittings.
Phil I
|
|
|
|
