Replacing a Toilet Syphon - Choosing the Correct size

[Skavenger]

Hi,

The Flush / Siphon in our cistern al has been playing up difficult to flush and has now got to the point where it’s becoming a real issue. It’s an old toilet and seems to have a one piece flush / Siphon. How do I ensure I get the correct size / type replacement.
Only markings on the top of the blue Syphon are the names “Caradon Bathrooms Ltd Made in England” and a clock face on its 96 and an arrow pointing to the 5 - is this Month/ Year of manufacture (May 96)?
Measured from the bottom of the flush to the underside of the cap of the Siphon (as per pictures) is 237mm. The outlet pipe into the toilet bowl has an external circumference of about 12cm.
I take it I empty the cistern, tie off the inlet (to stop water re filling, then undo the plastic nut on the underside of the cistern, disconnect the handle and replace?

Just need help getting the correct replacement. Screwfix or City Plumbing link would be best.

 

[HERTS P&D]

Buy this one:

https://www.screwfix.com/p/thomas-dudley-ltd-adjustable-siphon-237mm/9756F?gclsrc=aw.ds&gad_source=1&gclid=CjwKCAiA65m7BhAwEiwAAgu4JFmACL9oXCeCGeYQFMDl_aJks9CEhPRBS0l12-0ZTbCBzGpuVggUmBoCZSgQAvD_BwE&gclsrc=aw.ds

Andy

 

[HERTS P&D]

Don't tie up the inlet, isolate the water or drain dowmn.

Andy

 

[Skavenger]

I looked at that one thanks.

 

[Johntheo5]

You don't need to replace it, when you remove it, you can just cut a bit of plastic to replace the bit inside the syphon, you can see quite easily how to take it apart, the bit of plastic doesn't require to be a tight fit, it just pushes some water down the outlet to start the syphon effect when you piull the handle.

 

[ChrisJP]

It's true you don't really need to replace the whole syphon and you can fix it by just replacing the diaphragm.
However, a lot of replacement syphons are now two-piece, so the main syphon unit can be separated from the flush tube bit that exits the cistern. That means in future you won't need to drain the cistern and remove the whole syphon when you need to replace the diaphragm.

 

[Johntheo5]

No more pumping of the handle up and down, you will be flushed with success.

 

[Fredstudio]

Hi,

The Flush / Siphon in our cistern al has been playing up difficult to flush and has now got to the point where it’s becoming a real issue. It’s an old toilet and seems to have a one piece flush / Siphon. How do I ensure I get the correct size / type replacement.
Only markings on the top of the blue Syphon are the names “Caradon Bathrooms Ltd Made in England” and a clock face on its 96 and an arrow pointing to the 5 - is this Month/ Year of manufacture (May 96)?
Measured from the bottom of the flush to the underside of the cap of the Siphon (as per pictures) is 237mm. The outlet pipe into the toilet bowl has an external circumference of about 12cm.
I take it I empty the cistern, tie off the inlet (to stop water re filling, then undo the plastic nut on the underside of the cistern, disconnect the handle and replace?

Just need help getting the correct replacement. Screwfix or City Plumbing link would be best.

View attachment 366772View attachment 366773View attachment 366774View attachment 366775View attachment 366776

Sorry to ask another question in a post. But the measurement given here is also the overflow measurement of the syphon. Were older syphons all internal overflow even though toilets were fitted with an external overflow

 

[Johntheo5]

Mine is ~ 35 years old and hasn't a external overflow and neither had the original 55 year old one. This 35 year old one doesn't have a adjustable flush like the one shown above which has a blue plug near the bottom, its set to give a small flush, you can see the syphon breaker hole above it, you just move the plug up which will then cover this hole and uncover the lower hole to give the maximun flush, not quite as convenient as the two button flush though!.

 

[Johntheo5]

Deleted, double post.