Stumped - closely coupled cistern has no holes for donut bolt-on kit


7 Oct 2005
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United Kingdom
First time for me but I have an old toilet (25 years) which need a syphon replacement. It all looked standard from the bottom with the usual 2 screws either side of the 2 inch exit hole with donut etc but when I tried to undo the butterfly nuts, the bolt was so rusted it snapped on one side and on the other side I just lifted the cistern off (with no force) and could see the bolt and nut still coming through the pan hole. The metal plate had disintegrated with rust and the rubber mount was just about in one piece. After much messing I managed to cut the bolts to get them out of the pan holes and clean things up. From there I expected it to be a standard fit with new syphon (other than majority syphons seem to be 1.5 inch rather than my 2inch but thats an aside).
I was looking at a new close coupling cistern fixing kit and went to measure the cistern and was shocked to find there were no bolt holes by the syphon exit hole where you would normally feed through then tighten below the pan to get a good seal. The existing kit had the bolts for sure but I can only image these were not attached to the cistern in any way - very bizarre and I can't figure out how I will attach the cistern to the pan securely - photos included.


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1. Not all cisterns are fitted with bolts through the base passing through the back of the bowl.
2. The alternative is a metal plate. This is oval shaped, has a large hole in the centre for the pipe and a slot in each of the "wings" of the oval.
3. These have square shanked bolts. You fit the plate under the securing white plastic nut (secures flush valve / syphon), then the nut and tighten up. On some you fit the square shanks of the bolts (thread pointing away from cistern) before securing the plate, on others, you can slide the bolts on after securing the plate. You then fit the doughnut washer over the white plastic securing nut.
4. The next job is to fit the cistern onto the bowl. Should be easy, but often difficult to line of the bolts with holes in the bowl (left hand side of your IMG_1260 shows one hole). They then fall out of the metal plate!. Just persevere.
5. Fit the washers and nuts onto the bolts and tighten. Hold the cistern level and get both nuts (often wing nuts) finger tight, then tighten further starting with one full turn on each nut going down to 1/2 turn or less as all becomes solid. You need to keep the cistern level with the flat part of the bowl.
6. Have a look at Screwfix item number 84958 to see what it looks like,
Pretty much all new siphons come with a 1.5in outlet. As you note, older cisterns typically have 2in outlets. You used to be able to get plastic 1.5in to 2in converters but these seem now to have gone off the market. About 3 years ago I managed to get one of these converters but was told by the vendor it was the last one he had and he couldn't get any more.
Perhaps someone on this forum knows of a source of supply?
Thanks old buffer and chrisJP for the input/instructions - I have fitted quite a few toilets in my time and not really come across this type with the metal plate and no holes - though I am mainly fitting new ones rather than repairing old ones..
I think I have worked out what I need by going to city plumbing and looking at various kits. I have purchased the syphon, a standard metal plate kit and also a large donut ring to use instead of the one in the kit - basically the same as the one I took out as the one in the kit is quite small and the larger one sits nicely in the groove in the base. The city plumbing guy seemed to know what he was talking about and I took my old bits so hopefully I have all the bits and will give it a go tonight - fingers crossed


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Final update - I ended up using using both donuts and, after reassembly and testing, all looks good. It just didnt look right to have the cistern silmply resting on the larger donut, especially with the metal plat not being flat - so the smaller donut fitted nicely on th nut and then was a good fit into the larger donut.
I couldn't really figure out exactly what the previous setup was the the while coupling kit had pretty much disintegrated so it was hard to pice the components together. Either way its all done now and I hope not to have to do it again anytime soon :)
All my pans connect to the cistern like this. You push the flush valve through the cistern hole and using the flush valves large plastic nut to attach the metal donut ring to the flush valve. The rubber donut is then squash between the pan and the cistern and bolted down.
In my case and the reason it was a bit weird is that the donut that came with the coupling kit fits perfectly onto the syphon nut but its actually smaller than hole in the pan so it has nothing to push against - hence the second larger donut - which was also used in the original coupling kit but had worn through. see picture. The angle of the photo makes the coupling kit donut look quite big but it def is slightly smaller than the hole but seems to rest ok again the larger donut. After I had done it I did find a coupling kit on amazon that actually provides 2 donuts (large and small) that combine to something similar to what I have.
There is a fair chance that I have botched this in some way but I couldn't figure out an alternative combination that would give me a decent seal and as its not leaking anywhere I am tempted to leave as-is rather than try an alternative method.
Normally I would just go to Screwfix etc and get a kit which would be a simple fit but this just seemed a bit more complicated than it needed to be versus what I have been used to when replacing the complete toilet with a new one.
A bit wiser now anyway should I come across this again:)


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Wrong clamp plate you really need the ideal standard one
It's dead flat the bolt heads sit in indents at bottom of cistern
Also uses the much bigger O ring type seal that you have.
Sorry I wasn't clear - the coupling kit I bought was indeed the correct one with a flat plate etc - see picture - and I purchased the larger donut separately. my second picture of the other kit with 2 donuts was more to point out that I didn't realise there were kits that contained the 2 donuts available (regardless of flat plate or screw threw).


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hmmm - Do I track down an Ideal flat plate or do I stick with what I have? Firstly I guess I need to see if the toilet is Ideal as well - though no labels so not sure how I find that out. Having thought about it the flat plate could make sense as that would push up against the larger donut making the smaller donut possibly redundant and this would seem to better match the dis-integrated bits I had from the original coupling. I will at least see if I can get my hands on the flat plate optioned go from there - whether or not I fancy taking the whole thing apart again when its all working is another question but thanks for the clarification and it makes some sense Exedon
whether or not I fancy taking the whole thing apart again when its all working is another question
If it's working and not leaking I would leave it alone. If it ain't broke don't fix it!
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Having investigated further Exedon is 100% correct and the actual kit I needed was indeed the Ideal flat plate as that is pretty much what my original disintegrated one looked like i.e just a wide flat plate and large donut. Should I need to revisit this I will use the correct one but current setup with the 2 donuts and not-so-flat plate seems to be causing no problems so will leave alone.
Thats a lot of learning and much appreciate all the advice ..(y)


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