Dual flush, only doing the short flush now

[HDRW]

A few years ago I installed a Stelrad Doulton close-coupled loo, and the syphon that came with it was dual flush (quick push = short flush, hold down = full flush).

Recently it's been doing only the short flush even when you hold the handle down. Peering inside the cistern I can't see anything that could be the culprit (there's a plastic plug in the side, but that's tight in place).

The syphon is red with a brown top, labelled "Stelrad Doulton" and "DUDLEY".

Is there anything I can do that doesn't involve removing the cistern? I thought at the time it was a daft design that meant the syphon was "trapped" by the cistern/pan joint, and if I have to remove it I'll replace it with a Dudley Turbo 88 which has a much more reasonable design, IMHO! (Ironic that it's one of theirs I'll be replacing).

So, am I in for a cistern removal or is there anything else I can do?

Cheers,
Howard

 

[jeff the gasman]

Time to remove the cistern. There is a rubber plug inside siphon which blocks a hole when you hold the lever down.
Jeff

 

[HDRW]

Thanks - I was hoping there was another way, but I suspected there wasn't - that syphon nut trapped in the cistern-pan joint really decides it, as the mechanism is inside the syphon itself as you describe.

Cheers,
Howard