Since you say the pipe is 3", you will not find any flange that will fit inside it. And if it did, the opening would be so small that it would cause problems. Removing it like the Lowes man said is about your only solution. It can be done but you have to do it carefully since if you crack or damage the pipe, you will then have to replace the pipe also.
: One of our toilets was loose for a long time but not leaking. I finally decided to address the problem
: before it did start leaking and cause damage to the ceiling below. After removing the toilet and cleaning
: the flange (yuck!), I found a cockeyed closet bolt on one side. After removing the bolts which were
: mounted to the flange with a washer and nut, I noticed the flange is cracked on the side where the
: cockeyed bolt was. The flange is ABS plastic guled onto a 3" ABS waste pipe. The screws that secure
: the flange to the subfloor are very rusty and could break off if I try removing them to install a repair
: kit or flange on top. I would also have to break some ceramic tile from aroud the flange, but that's
: no problem or concern. My repair plan would be as follows in order. I thought I would ask here before
: I make a lesson out of a possibly expensive mistake.
: 1) Try slotting the rusted flange screws with a dremel tool (hope & pray they don't break off) and
: then install a repair kit on the existing flange using new screws. If they break off then.... #2.
: 2) Cut the old flange out using a rotozip or dremel tool. This would leave me with the 3" waste pipe
: with part of the old flange pipe glued to the outside, but the pipe would be below subfloor level. I could
: then insert the new flange inside the 3" pipe and secure to the subfloor using new screws.
: Not my most favorite plan, but I think it might work.
: Never heard this one... is it true?
: The plumbing guy at Lowes says if I cut away part of the old flange, I can use a hammer & screwdriver
: to break the glued joint and remove the remaing flange. He said he's been doing it that way for years,
: but I always thought glued joints couldn't be broken apart once the glue sets.
: Your thoughts and advice would be much appreciated!
: Thanks in advance....!