Toilet Ring

Regarding my last post concerning a suitable toilet ring for a floor mount, rear flush toilet. I got this foam ring from a specialty plumbing store in my area. Does this look like the right type of solution?? Doesn't seem like it will work properly to me, even though it does fit the toilet nicely. Doesn't seem to match the flange very well though! If this is not the right ring, what do I use and where do I find it? OSH and HD only carry standard wax rings.

BTW - The guys at the specialty plumbing store said to just use a standard wax ring!!

flange

From your pictures it appears the flange is flush with the wall surface. If so the the gasket has to protrude from the back of the toilet far enough to be compressed when you install it. I would get a second gasket and slice it down the middle to create a thinner gasket, then put that in the toilet recess first and follow it up with the regular one.

Sort of same issue

I had a leak under/around/behind my floor mount wall outlet toilet. I removed the toilet and found it was a gooey mess of lots of wax from a failed wax ring. The toilet is an American Standard but no longer in production. The closest model I can find is the Yorkville but this has a standard flush system.

I got a special sponge gasket that looks similar to the one in his picture. My flange though sticks out of the wall approximately 3/8". The metal flange ring was rusted and broken. I got a replacement 2 piece flange ring to fix that. The pipe is sch 40 PVC 3". The closet flange is 4" x 3". The flange is solvent welded to a street elbow.

Here are my questions about this arrangement.

The closet flange appears to be a standard floor style flange. Is this normal flange for a back outlet floor mount?

Because it is solvent welded and I can not get at the other end of the elbow easily, I suspect changing the entire flange is impractical.

The ring is off the wall surface by about 1/4". Because it is a 4x3 flange, there will be an area at the bottom of the flange which I believe will hold wastewater in there, behind the "sponge" ring.

Next issue is the center of the flange is about 4 1/8" above the subfloor. The center of the horn at the rear of the bowl is 4" from the bottom. How sensitive to leaks are these toilets if the center of the horn is not centered in the flange? I'd like to put 1/4" underlayment on the subfloor. The toilet used to sit on carpet so I suspect the underlayment will not raise it too high.

I am worried the ring will not compress enough to seal the flange tightly and if even it does the back of the toilet base will not meet the wall.

Any ideas would be appreciated. We have a second similar toilet. Although it is not leaking I suspect it did at some point for prior owners and expect to see wax around it too.