Close coupled cistern has been leaking from the bottom and coming out through the bolt holes for the doughnut clamp. Removed cistern and found flush outlet pipe had broken away on thread. Replaced flush mechanism and still have the problem. This is when the tank is full and not just on flushing. Cistern screws into wall, so I'm wondering if I can skip the metal doughnut clamp so I can get the external flush nut 'flush' fitting at the bottom of the cistern.
You need to replace the doughnut washer. When you remove the cistern you break the seal and can never get the original washer back in the same place. Just get a new one of the same type. You should not have to put any jointing compounds anywhere near the base of the cistern/flush pipe. I do this for a living.
Jock
February 2009
If it leaks without flushing you do not have a watertight connection at the base of the cistern. If you dispense with the metal clamp you will not have sufficient pressure on the doughnut seal to prevent a flushing leak.
You are using a sealing compound at the base of the cistern conection --aren't you?
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