Old American Standard toilet from around 1954. Has some Fluidmaster components in it.
It works OK but about 4 times/day it pumps maybe an additional gallon of water in, so it has a slow leak.
I checked the stopper and it's aperture: both look fine, but I spread a little vaseline on both to help insure seal. No help. Overflow tube, etc look OK.
Visual inspection looks OK but it leaks. Any ideas?
Thx, Willie