On Tue, 23 Feb 2016 10:17:49 GMT, DerbyBorn
wrote:


Any suitable sealant. There is no pressure and hopefully won't be
used.


The overflow chamber gets wetted when the plug is removed as well - water
can flow either way through the slots.

Ah, of course. The required solution for the desired outcome will be
the same though. ;-)

I've been there when a guy re-doing my Mums bathroom struggled for
some time with this very issue. I took it all the bits, worked out
what had to be done (some sealant applied to the thread on the final
nut) and left him to get on with the job. ;-)

Cheers, T i m