replaced flap - toilet still runs/leaks
I just replaced the old flap (that was about 2-3 years old) with the exact same brand...and it still leaks; tank refills at least 3-4 times an hour. if I manually press on the flap it seals tightly..until the toilet is flushed again, when it doesn't seal as tightly on its own.
The tank has a brass pipe and fitting; wondering if I need to sandpaper or gently file the brass ring into which the flap fits to create a tight seal. I believe I had to do this once before when I replaced the flap, but I don't remember what I may have used. We have a water softener system so it is NOT hardwater build-up.
Re: replaced flap - toilet still runs/leaks
First, be sure that the lift chain is not a little too short so that it holds the flapper up slightly.
If, after you try smoothing the brass seat (which is difficult to do without creating more problems) and it still leaks, there are stick-on seats of plastic that go over the top of the old. Can't remember the brand, but a plumbing store that specializes in repair will know what you want.