How to disasemble Geberit concealed cistern flush mechanism?

[matei]

Hi all,

I am trying to take apart my Geberit Omega 12 cistern flush mechanism due to overrun after flushing. I've been able to find videos of similar units to mine - but not the same one - online, which enabled me to take it apart about 75%.

I can't figure out however how to actually disassemble to mechanism itself, or how to remove the... emmm... long bit that extends to the base of the cistern (sorry for not knowing the actual term itself!).

Any advice appreciated!

thanks!

This part - I can't figure out how to actually take it apart w/o breaking it

And this bit... I can't figure out how to take it apart to remove it from the cistern. I got as far as folding the plastic arms down:

 

[matei]

Nevermind... I just used common sense to take it all apart. This Geberit plastic is quite strong, I had to apply a decent amount of force but it all came apart in the end.

The issue I had was blisters forming on the silicone washer at the bottom of the cistern. I didn't know that they'd form on silicone as well, learn something new every day!

 

[terryplumb]

Well known problem with that manufacturers seals. Pile of junk in my opinion.

 

[matei]

Not impressed - that seal costs maybe a quid to make and they're selling it for a load of money.

Anyway, the big issue was sorted - but now I have a new one... or perhaps it contributed to the original problem. The plunger arms seem to put pressure on the "rabbit ears" and the result is a constant trickle of water. Not like before, but just enough to have a minute "hiss".

I've tried leaving the unit open, w/o the flusher panel attached, and this doesn't happen. Only after I re-assemble and then after a few uses. Really annoying. Is there any way to adjust these things?