Look how ugly it is back there; whoever put it in should have done a better job, especially where the pipes meet the floor. I might try making up a panel at a later date.
Okay, so the loo was taken apart, the bad syphon replaced, and put back together again. It was time to put in the new inlet valve. Here it is below. This was an awkward fellow to fit; there is no space in here at all.
The new inlet valve’s float was fatter than the old one, and was too big for the available space. I reused the old float. There just isn’t space enough for that big blue float to move!
I turned the water supply back on - this last photo shows the cistern filling back up. When the water reaches the level of the float, the rubber stopper in the inlet valve shuts off, preventing the cistern from over filling.
All done - a working loo, minus the plumber's fee. I still can’t warm to this design though!