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 Could NON-leaking toilet cause sewer gas smell
Author: spanky67 (CT)

I know there are a zillion posts on sewer gas smells in basements. My question is, could a sewer gas smell come from a toilet that operates perfectly and does not leak?

Every trap has water. Every fixture operates normally. I've replaced wax ring once with an oversized one. Then replaced it with a stackable composite ring (2 of them stacked). Smell remained in both cases. Shower next to toilet drains into toilet stack. I plugged shower drain (thinking no trap in shower and smell backfeeding there) and left toilet installed. Smell still terrible. Last night pulled toilet and plugged...keeping shower drain plugged as well. Smell totally gone...almost instantaneously. Has been 24 hours since plugging both and no smell.

I'm open to any suggestion. I think it's a bad toilet, but really don't want to drop the $$$ on a new one, only to have the smell return.


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 Re: Could NON-leaking toilet cause sewer gas smell
Author: North Carolina Plumber (NC)

I've saw brand new toilets that emitted sewer gas, verified via smoke test. An older toilet would not go bad and let gas escape unless the outlet had cracked. Is the flange sitting atop the finished floor ? Toilet setting solidly with no wiggle or rocking ?

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 Re: Could NON-leaking toilet cause sewer gas smell
Author: packy (MA)

take the tank off the bowl.
turn the bowl upsidedown and inspect the flange area for hairline crack.
use whichever method you feel most comfortable with to reset the bowl. BUT, while the bowl is upside down put a good bead of clear silicone caulk onto the outside edge.
now set the toilet, tighten securely and wipe up any excess silicone.
fill the bowl with water and see what happens.
quite frankly, i can't see how this could smell...

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 Re: Could NON-leaking toilet cause sewer gas smell
Author: spanky67 (CT)

I should've said toilet sits perfectly on floor when secured (no rocking).

This basement was finished by a prior owner. I'm not a pro by any measure, but have completely gutted 2 50+ yr old baths down to studs and complete rebuilds. This was a no permit, basement finish, hack job. Tile shower straight onto plywood, no shower trap, covered junction boxes etc. Using that info, I can only gather this was a big box toilet. So, although it says American Standard, I'm guessing it might not be the best unit from the factory.

The flange does sit slightly below the tile. That has been a thought also, but why does the smell go away when the toilet line is plugged? Wouldn't it still smell?

Not sure I want to take the calking the bottom genie out of the bottle, as I don't want to have to undo it if not the issue. I read another thread that suggested (as a temporary "test") reinstalling the toilet and taping off the bottom edge. I can only assume to do what silicone would do without the permanancy. Would duct tape, completely sealing the bottom edge be enough to hold off the smell long enough to eliminate the toilet?

Lastly, if not the toilet...any other thoughts?


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