Any help appreciated please. A slow leak appeared beneath the WC cistern last week. It's a low-level 2 gallon cistern with flushpipe, and the leak is coming from between the base of the cistern and the top of the siphon backnut (definitely not condensation). I replaced the flushpipe and siphon, using the appropriate siphon washer on the inside of the cistern, but the leak persists.
I've now made/remade the joint four times, carefully centralising the siphon/flushpipe in the cistern outlet each time, but I cannot resolve the problem. The leak is extremely small but VERY irritating.
The last bit of significant information: there's a very fine hairline crack on the inside bottom surface of the cistern (about 5" long) which runs into and all the way through the cistern outlet from top to bottom, but is NOT visible on the underside of the cistern.
Though clearly visible, I would definitely describe the crack as hairline. Could this really be the source of the problem, and the reason I'm having so much difficulty repairing it?
Thanks in anticipation.
I've now made/remade the joint four times, carefully centralising the siphon/flushpipe in the cistern outlet each time, but I cannot resolve the problem. The leak is extremely small but VERY irritating.
The last bit of significant information: there's a very fine hairline crack on the inside bottom surface of the cistern (about 5" long) which runs into and all the way through the cistern outlet from top to bottom, but is NOT visible on the underside of the cistern.
Though clearly visible, I would definitely describe the crack as hairline. Could this really be the source of the problem, and the reason I'm having so much difficulty repairing it?
Thanks in anticipation.