John Smith wrote:
....
Both toilets are more than 10 years old. I understand that the flapper
probably has passed its useful life. I just don't understand why it did
not leak before cleaning but did so after cleaning.

Toothbrush is quite soft. The other brush is a bit harder. Yet, there is
no scratch marks on the rubber. The rubber has some "goose bumps". I can
only guess that gunk filled up the gap between "goose bumps". After
cleaning, the gunk is gone and the flapper starts to leak.

if it isn't smooth then that will cause a leak.
using a thin layer of vaseline (or some other water-
proof grease) might smooth it out enough to seal
completely.


songbird