I completely gutted and remodeled a small bathroom. During the drywall work, I stuffed a few rags into the pipe in the floor for the toilet to keep drywall and stuff out of the hole. Room is done and new ceramic tile on the floor. Haven't removed the rags until today when I was going to re-install the toilet.
I began preparing the flange using a scraper to remove rust, etc. On the inside of the flange there was some material, but, I'm not sure if it was clay, dried up drywall dust and compound, or something else. Anyway, the material was very loose and crumbled, so, I basically scrapped it away down to the cast iron flange. I'm thinking that was a mistake.
Attached are a couple of pictures. The outer circumference of the flange is 7 1/4 inches measured on the outer edge across the bolt notches. The inner circumference of the flange is 5 1/4 inches measured from the inner top lip of the flange from side to side. The inner wall of the flange drops approx 3 or 4 inches to a 90 degree elbow (I know as soil pipe). I did not disturb any of the seal. I have never seen a flange with any material like what I scrapped away. Also, the home was built in 1960, but, this is a second bathroom that was added sometime in the 1970's.
The wax seal fits inside the 5 1/4 opening of the flange. Basically, there would be nothing to seal against. I'm at a loss as to how to re-install the toilet.
Is there some type of clay insert or other material that would fit inside the cast iron flange??
The flange should be at to 1/4" above the finished floor, yours looks like it is below. And the oversized flange is you main issue. There is a vinyl flange insert that should fit inside your flange and solve both problems.