not being the best of valves around, i had alot of greif with one before.
you say you've fitted a new one, so that counts the seal out.
all you haven't changed is the base. but then rather than chuck money at it i'd rather buy a new valve but a descent make.
I was told this was the only one i could use for the oval push button? I have now been infromed I can use a fluidmaster, is this correct?