Hi, I am in the process of replacing a syphon in a toilet cistern. I have removed the cistern and syphon without a problem. However upon cleaning the cistern around the syphon outlet hole I have noticed a lump of porcelain on the upper side of the hole at the edge. This is porcelain and not lime scale, it is 2-3mm high and about 10mm wide with rough edges. This is preventing me from getting a water tight seal when installing the new syphon unit. I have tried without any success to remove the lump. Any ideas?
Is it possible to remove the lump of porcelain without breaking the cistern or do I try and pack all around the outlet hole with sealant, if so what type of sealant.

Hi aggyblue

Have you tried purchasing a wax gasket with a NEOPRENE or URETHANE seal inside of it? If not, I would try that before messing with the china/porcelain cistern...;) These gaskets are great at accommodating irregularities in the bowl or flange!

Mark

Ok, I tried using lots of sealant between the cistern and syphon gasket, this didn't work but the leak wasn't as bad.
Third attempt, I used two gaskets. I cut a piece from one gasket as close to the shape of the lump as I could and used sealant to fix in place with the cut out around the lump. Then the second gasket was put on top of the first with plenty sealant between them. The syphon was then secured in place. This has worked a treat with no further leaks.