replacing 2-piece cast iron toilet flange
We recently noticed a bad leak in our basement that was coming from the pipes leading up to our second floor toilet. Have traced it to the toilet drain.
I was hoping it was simply a wax seal that needed replacing but when I got the toilet out of the way, replaced the wax seal and started to reattach the bolts that hold the toilet down, the rotten old cast iron flange broke. I was able to detach the broken piece from its base by loosening the 4 bolts holding it down.
I'm wondering if they still sell these two-piece cast iron flanges and if the size and bolt layout is still the same? I've been looking at videos and found one where the flange was sealed to the pipe with lead solder, and also saw a compression fit pvc flange that goes inside the drain pipe.
The drain pipe is old cast iron. I'd like to replace the flange the best way possible - best as in the way that be leak-free and last the longest. If I can find a replacement bolt-on top piece for the flange, do I need to add any additional sealant other than the wax seal? Also, should the flange be flush with the tiles or suface mounted on top of the tiles? The plumber who installed this toilet 10 years ago (using the existing 70-year-old flange) had put a bunch of what looked like spackling compound under the toilet to raise it up slightly and I'm wondering if he did this because it was loose or wobbly.
Here's a couple of pictures. The first is the flange top separated from the bottom part. The second is what the current (broken) flange looks like when set into its location. It sits on top of the tiles (not flush to the floor).
Attachment 21792Attachment 21793
Thanks in advance for any advice!