I have a similar problem.
I replaced the flusher unit a while ago and noticed the standard B&Q kit seemed a little bigger.
It seems when the water flows down the internal overflow (of the flusher) it is not gooing into the well that leads to the pan, and gently drips down the side and back.
Drip is also slow, hence pretty sure that as the water trickles in, it trickels out the overflow.
Here is how I (non-plumber) replaced the flusher
(If you have a tap to shut of the incoming water, it is easy enought to remove.)
- close water supply
- flush and mop out the water in cistern
- disconnect water supply and external overflow
- unscrew the two bolts/screws holding the cistern to the pan
- unscrew any bolts holding the cistern to wall
- lean it foward to pop it off
- should be easy enough to replace the flusher unit / seals etc
I think the trick is finding the right flusher unit.
I tried the simple unit with just a plug in the hole attached to flush handle (no funky mechanism, to break)
It wouks really well, but I am pretty sure the piece that stick out of the cistern is a tiny bit too big.
Will let you know if I have any luck.
Bruce
February 2008