leaking toilet

[lala]

I have a problem with a plumbing leak. When ever I have a main line
stoppage the water backs up into my bathtub and then it comes out
from the bottom of my toilet. It never overflows the toilets just from
around the bottom on just 1 toilet. That bathroom is a half bath and
is at the end of the drain line. I asked the plumber that came out to
unclog the main line why it does it and he did not know. My thought
was that it is a bad wax ring but it only leaks when the main line is
clogged. I have put in my own faucets but have never done any
work with toilets Is this something I can do myself or should I get
a plumber to do it. Any advice would be great.

 

[Jadnashua]

If you can lift the toilet, you can resolve fixing the seal (probably). The reason I say probably is that if the pipe and or flange are rusted out or damaged, it will be harder to fix right.

When you flush, the outlet of the toilet normally isn't as big as the pipe you are dumping into, so think funnel - unless there is a backup in the drain, you may not see a leak because all (or hopefully all) of the waste is going down that big hole.

A wax ring is usually used to create a seal between the toilet and the flange. It's basically shut the water off, flush the toilet to get as much water out as possible, disonnect the hose or pipe going to the toilet, unscrew the bolts holding it down (this can be a pain sometimes if they have rusted - use brass or SS when you put it back on) and lift it up and out of the way. If there is caulk around the base, it may require cutting that but it doesn't sound like there is any.

Then you will expose the flange. Scrape off the wax on it and the toilet. Check the condition of the flange and the subflooring. Unless the bolts are brass and still in good condition, replace them. Set the toilet back over the flange to check for wobble. If needed, use some shims for a trial (coins can be used, or they make plastic toilet shims). Note where they need to be, then remove the toilet, add the wax ring, set it down over the bolts and squish it back down in place evenly back and forth as evenly as you can keeping in mind that the wax is not a spring...once it is compressed it won't come back so you don't want to press one side down, then the other all the way as if it rocks like a lever, it could break the seal. Once you have it all the way down to the floor, resecure it with the bolts.

You may want to take advantage of this time to replace or check the condition of the shutoff valve and supply hose. Reconnect the water and you're done.

This sounds like a lot, but might only take 15-minutes unless you have to hacksaw off the old rusted bolts or fix the flange. Until you have it off, you won't know the condition of the flange. If it has been leaking for awhile, the subflooring could be rotten. It could take a lot of work to repair things. If the flange is shot, depending on what else is happening, there are repair rings and various parts that can make it usable without having to replace it entirely...depends on what you see.