Non-standard close coupling on old Twyford toilet

[Denis247]

http://www.replacementbathroom.co.uk/twyfords-siphonic-brampton-wc-siphon--air-extractor-3082-p.asp

Thanks, but Brampton cistern wont fit 4-hole pans, unless there's a convertor plate or something available (I have a call into Mathewson & Rosemond, mention in this thread a few posts up). Apart from the mounting, the cistern looks the same.

 

[Denis247]

Try www.brokenbog.com

Thanks, I tried them already.

 

[1001things]

Another here with a Twyford 4 bolt double trap siphonic. In this case perfect condition externally. But not flushing properly.

Pull the lever (fast or slow makes no difference), water fountains up out of the hole at the top of the lever side of the siphon (where the lever passes through), level in the cistern drops until just below the top of that side of the siphon and then starts slowly refilling. Meanwhile water flows initially into the pan both from the 2 nozzles at cistern end and in a stream from the opposite end. Level drops, that stream ends, no gurgling reached and just left with the water flowing out of the 2 nozzles.

From what I understand this would be due to the diaphragm being perforated. Right?

But:
a) what effect does the lack of rubber 'washer' on the siphon have?; and
b) if I take the cistern off the pan to get to repair the diaphragm, do I have above a 0% chance of getting it back together again? (I'm guessing whatever is around the connection will crumble when it gets moved)

Am attaching a photo of the top of the in situ siphon (#1) together with photos of a spare I have which is identical vintage and, I'm 99% sure, came from an identical model, showing a rubber wahser or similar on top of the siphon and also the parts that connected through to the pan.

Any input appreciated.

Siphon #2 Base

• 1001things
• 7 Mar 2018

Spare siphon

Siphon #2 Top

• 1001things
• 7 Mar 2018

Spare siphon

Siphon #1 Top

• 1001things
• 7 Mar 2018

Siphon currently installed

 

[Hugh Jaleak]

I'm not familiar with the Twyfords version, but assuming it works on the same principle as the Royal Doulton double trap syphonic, then the seals on the syphon tail, where it mates with the pan, are vital for correct operation. Basically, there is an aspirator (or 'bomb'), in the tail of the syphon, that when the flush commences, causing a vacuum in the middle trap. Once the flush is going, then it sets up the syphonic action so atmospheric pressure pushes the contents of the pan out through the traps, to the drain/soil pipe.

Biggest problem I found with the Royal Doulton pans was the narrow middle trap, which caused the pan to block if any more than about 3 sheets of paper were flushed in one go.... Some diagrams and more info in this thread, https://www.diynot.com/diy/threads/double-trap-siphonic-pan-help-needed.389820/