I went to fix toilet wobble. After pulling toilet from floor, found broken flange(appears to be cast iron). After much beating and prying, I separated flange from drain pipe. It was affixed with pliable metal material(solder? Some sort of weld?) When drilling into concrete foundation, I found said foundation to be mush around drain pipe. This leaves me with no anchor point for the new flange. Any "easy" fix for this problem? My welding skills are not non-existent, however they are close. Perhaps cleaning out mush and pouring quick setting concrete? Drain pipe is 4". Thanks in advance.

Hi john. In your situation I would recommend a hydraulic cement be poured and left to harden as per instructions on can (hydraulic cement expands a bit so will lock it up tight). Then install a 4" cast iron twist and set flange... see pic. (soap rubber gasket). Then secure that with concrete screws or anchors. That should get you up and running.

The twist and set flange should be purchased BEFORE you pour hydraulic cement in case you cannot find one of these... but should be easy to find at home supply store OR at the local plumbing supply store.

Other than that could always install a new 4" (deep) cast iron flange and lead and oakum it in place (That is what "solder" was.. it was lead -->>You could have just drilled the lead out and then pulled up ;) but not important now). That would require you to buy bag of oakum and 5lb block of lead and a ladle to melt the lead. You would set cast iron flange and then pack oakum to about 1 to 1.5 inches of top of pipe and then pout lead to top of pipe. Then you would peen the edges of lead to seal at pipe edges (inside edge and outside edge of pipe).

If you do cast iron flange...do not set hydraulic cement until AFTER you install the flange.

Hey, that should do it... keep me posted on how it worked out.

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If the pipe or flange is damaged, there are Special Replacement Flanges just for this situation.

Flanges come in different sizes -- depending on the manufacturer -- bolt spacing is important

Carriage bolts on flange may be a good idea -- Hex holds head when tightening hold down nut

Toiletology 101: Replacing the Toilet Wax Sealing Ring

Whether you are installing a toilet for the first time or reinstalling after repairs, ALWAYS use a new wax-ring.