On May 21, 10:47*am, c_shah wrote:
I replace my 20 years old toilet (KOHLER) with a new fill value (made
by MJSIwww.gomjsi.com) and a flapper. It still leaks..at about 4
hours tank is empty looks like it is leaking into bowl (no water
around toilet area)

At this point I am not sure what could be causing it to leak? should I
try another flapper...

The flapper seat must be smooth, just changing the flapper does no
good if the seat is corroded or has gunk build-up.