Replacing the siphon on a close coupled toilet - sizes?

[fliptopbin]

Hi all,

I'm replacing a siphon with a split diaphragm and have everything in bits, but not sure what I'm ordering to replace it. The existing siphon has a 2" outlet - I have decided to replace it with a Fluidmaster push button which appears to be 1.5" with an adaptor (I think just a rubber thing that allows you to use it in a 2" hole). My issue is that I want to replace the sealing doughnut and hardware under the cistern. I guess I need one for 1.5" outlets, but will the doughnut seal be too small for the hole in the base of the toilet, which is 2.5" plus... The toilet is a Fired Earth "Burlington" if it makes any difference...

The close couple kit I was looking at is this:

https://www.toolstation.com/close-coupling-kit/p85615 - the technical data sheet says the outside diameter of the rubber doughnut is 80mm...

 

[CBW]

You might be better searching for a 2” syphon, which returns some, Viva being one which has a cradle suitable for 1.5” and one for 2”. You’ll also need a 2” donut washer and kit. Do a search for 2” close coupling kit.

 

[fliptopbin]

Does it make much difference as long as it fits? I mean, does the 2" flow more? The reason I picked the one I did was it got good reviews, push button conversion, and 2" ones seemed rather thin on the ground. Also I didn't know mine was 2" until I got the cistern off the wall just now (kindly siliconed on by the previous person to work on it!)

 

[CBW]

2” will obviously allow slightly more water through, but apart from that don’t think there’s any difference. If it doesn’t leak when you’re finished, then you’re good to go (excuse the pun).