To replace the diaphragm.you'll actually have to split the loo from where the cistern joins the pan - there are 2 wing nuts underneath to do this. So, turn the water off, flush the loo, disconnect water inlet pipe and overflow (if it has one), separate the cistern from the pan (tip the water out) and you'll see the large nut that holds the syphon in place together with a large rubber or foam 'doughnut' washer that you should replace as well. Disconnect the flush wire from the syphon, undo the large nut and the old syphon comes out. Tip - there are 2 sizes of syphon so get the right one. Tip - buy a new doughnut washer as well, and apply silicone sealant to it before you rejoin the cistern and pan. Cheers!
John, January 2008
