I have an old American Standard toilet and there is a slow leak between the tank and the bowl. I replaced the N-3055 feather valve and the slow leak remains. The metal seat feels smooth but looks like it might have tiny nicks or corrosion. Since it was not leaking before I changed the feather valve, I am thinking that the replacement feather valve was old and warped. (I bought the replacement from a plumbing store on ebay.)
Should I buy another feather valve from another plumbing supply store?
Should I replace the metal seat (which would be a bit of a pain, and I do not know how to replace it).
Is there a replacement kit that would take care of my problem with minimal effort?