Dudley Turbo flush

Hi, for some time our toilet has been hard to flush, it's a Dudley Turbo 88 syphon which when I removed I noticed the diaphragm was split and also the clear plastic stopper was missing. I cut some plastic sheeting I had to size to replace the diaphragm and cut a cork to shape to replace the missing bung. This had marginal success and I could flush it ok as I had the 'knack', but visitors and the kids still struggled.
So I've just bought a new Dudley Turbo 88 and simply replaced the blue bit. Bingo. Easy to flush now. Except that it doesn't seem to be the most powerful flush in the world. The water cascades into the bowl ok, and for a fair amount of time, just not very powerfully.
I noticed the instructions makes mention of 2 white plastic stoppers near the bottom of the unit, and says -
"6 / 7 / 9L convertible
6L Nominal flush (cistern & WC pan installed from 1st Jan 2001) - remove upper white plug only

7L Nominal flush (cistern & WC pan installed after 1st Jan 1993) - remove lower white plug only

9L Nominal flush (WC pan installed before 1st Jan 1993) - leave both white plugs in place

I have no idea whether ours is a 6,7 or 9L system. It was installed around 2000 so I'm guessing 7L. Anyway by default both white plugs were in so I tried removing the top one and then replacing it and removing the bottom one - couldn't really notice any difference at all in the flushes for each one.

Can anybody advise if I should be doing anything else to make the flush a bit more powerful - I'm not after the Niagara Falls but a single piece of tissue paper can take a couple of flushes to get rid of, even though like I say plenty of water comes in, swirls around but just not very powerfully.

Thanks in advance.

might be the shape of your toilet

Did you buy the right height replacement for your cistern? Is it the same as the one you took out? They do come in different sizes and the wrong size could alter the flush velocity. A reasonable way to check the water capacity would be to isolate the water to the cistern, empty the water by flushing it and scooping out the remainder and using a 1 litre jug to manually refill it from the basin tap to see how many it takes to get it to it's usual fill line.

Fit a flapper valve.

You will not get 'power' from any flushing device if you've got a close coupled or low level cistern. Not enough head of water. High level cisterns can actually be too powerful, sending water all over the floor.

A misconception about the Dudley Turbo syphon is its name. Turbo has nothing to do with the flush, it works the same way as any other syphon. It is due to the speed the syphon can be repaired, it being a 2-part syphon therefore negating the need to completely remove the syphon to replace the diaphragm.

Charnwood said:

Fit a flapper valve.

You will not get 'power' from any flushing device if you've got a close coupled or low level cistern. Not enough head of water. High level cisterns can actually be too powerful, sending water all over the floor.

A misconception about the Dudley Turbo syphon is its name. Turbo has nothing to do with the flush, it works the same way as any other syphon. It is due to the speed the syphon can be repaired, it being a 2-part syphon therefore negating the need to completely remove the syphon to replace the diaphragm.

Click to expand...

"Flapper valves" are the best thing since sliced bread IMO, I always try and convince customers to have them fitted these days, a Bit more expensive than a flush unit, nothing can really go wrong with them and the flush can be adjusted every time the WC is used. Bonus is they also have their own built in overflow
When changing over the Flush unit I recommend changing the float valve system at the same time, and fit a Cistern fill valve, no more worries about the float ball sticking, changing worn washers etc.

Thanks. The height of the new one is the same as the old one. I've established that our cistern is 9L so the 2 white plugs are correctly in place. To me it's just a bog standard (excuse the pun) toilet. Today on a couple of occasions I had to flush twice in order for it to flush. Just don't know what is wrong with it.

Is the c-link the same size as the old one (the metal loop between the handle lever and the connection on the syphon) so that the handle is in the same position as it was when it flushed well? If you aren't getting the full lever range to create good suction this could mean you have to pump it more than once.