I have an old wc with a 15mm (?) copper inlet pipe joined to the threaded end pipe of the plastic valve. It leaks and I bought another brass nut and some ptfe tape but it still leaks. Is there a different way that it could be connected or can you still get metal ballcocks so that a compression joint can be used?

Barry Maud., April 2011

try putting the ptfe tape, between the brass nut" and the olive"on the brass nut side of the olive, put a good bit on , keeping it tight , put some on the plastic threads as well , the plastic threads might be half inch, and the brass nut ,is 15mm. you can still get a brass /copper ballcock . with 15mm , but it will have to fit into the cistern, and be able to move up and down ,with out it getting stuck in the body. that will work no problem if its fits, B&Q, or any hardwear..

l, April 2011