Mysterious toilet leak in front

[wsween]

Good evening, all. I have had a hell of a time with one of my toilets. I’ve replaced the wax ring a number of times, thinking maybe it was done improperly, even had a professional plumber do it once. Each time, the water shows back up in the same spot. I recently replaced the tank to bowl assembly, fill valve, etc, thinking perhaps it was running down the toilet and creeping to the front from underneath, but it is still there.

Is it possible there is a small leak under the toilet itself causing this? I’m not really sure what else could be causing the water here.

 

[Reach4]

A small crack in the toilet is possible.

 

[Sponsor]

 

[Breplum]

Color the tank water with food coloring can help locate. If that doesn’t help, then we pull the toilet and set on saw horses and then look. Bench testing like this is definitive. No guessing involved.
I’ve seen a handful of cracks on undersides, but usually with enough light, you will see external porcelain crack

 

[Reach4]

Let's examine the symptoms in more detail. If you suck up the water with the wet-dry vacuum, or even just use a rag etc, does the floor stay dry until the next flush?

Your installation is not typical IMO-- typically there is caulk or something around the base for about the front 80% to 90%. Shockingly, that caulk is structural on some toilets (not yours -- I just threw that in for some reason). In your case, I think the lack of caulk has worked to your benefit in that it gives you earlier warning. I am not a plumber.

 

[wsween]

Let's examine the symptoms in more detail. If you suck up the water with the wet-dry vacuum, or even just use a rag etc, does the floor stay dry until the next flush?

Your installation is not typical IMO-- typically there is caulk or something around the base for about the front 80% to 90%. Shockingly, that caulk is structural on some toilets (not yours -- I just threw that in for some reason). In your case, I think the lack of caulk has worked to your benefit in that it gives you earlier warning. I am not a plumber.

So normally I caulk, but I was waiting on this install to see if the water comes back. The water appears to be there regardless of the last time I flushed, and as you can see, it’s not a lot of water—just enough to warn you something is wrong. It still seeps under the caulk on the grout when it is caulked, though.

 

[Reach4]

Does the level of the water in the bowl drop, after the minute or so where some dropping is normal?

When you have not flushed, but top up the water in the bowl, does the puddle get bigger?

Is there any time there is not a puddle, such as you turn off the stop valve, flush the toilet empty, clean the puddle, and wait? I am wondering if there could be a small leak in a pipe in the slab below the toilet. This is the only thing I can think of that would not be solved by replacing the toilet.

 

[wsween]

Does the level of the water in the bowl drop, after the minute or so where some dropping is normal?

When you have not flushed, but top up the water in the bowl, does the puddle get bigger?

Is there any time there is not a puddle, such as you turn off the stop valve, flush the toilet empty, clean the puddle, and wait? I am wondering if there could be a small leak in a pipe in the slab below the toilet. This is the only thing I can think of that would not be solved by replacing the toilet.

I don’t notice the water level in the bowl going down—maybe it’s leaking too slowly to make an impact in between flushes?

That’s a good idea about the shutoff valve. I could try that, but I am fairly confident there is no water line in the slab there—the intake runs in the wall behind the toilet, and it’s dry there. I may just go ahead and replace the toilet and see if that fixes it.

I did put some toilet paper underneath it a day or two ago, to see if it was wet. After about an hour, everything was dry, but the toilet paper is wet now.

 

[Fitter30]

Toilet flange even with the floor? If it isn't maybe two wax rings after inspecting toilet .

 

[wsween]

Toilet flange even with the floor? If it isn't maybe two wax rings after inspecting toilet .

Yea that’s been part of my problem. The flange is well below the floor, more than half an inch. I’ve put in one of those Korky foam wax free seals (among others over time). I don’t feel like the seal is the problem. The last one I had was installed by a licensed plumber and when I pulled it, it looked good. I only pulled it because I saw the water even after his install.

 

[Reach4]

Yea that’s been part of my problem. The flange is well below the floor, more than half an inch. I’ve put in one of those Korky foam wax free seals (among others over time). I don’t feel like the seal is the problem. The last one I had was installed by a licensed plumber and when I pulled it, it looked good. I only pulled it because I saw the water even after his install.

Ahh....that could explain it. Korky says that if the top of the flange is 3/8 inch or more below the finished floor, stack two Korky seals.

https://www.korky.com/sites/default/files/2023-09/pk0591_-_6000bp_instructions.pdf section 4d)

Some people with low closet flanges use spacers, made for the purpose. Some put silicone RTV sealant beneath each spacer.

 

[wsween]

Color the tank water with food coloring can help locate. If that doesn’t help, then we pull the toilet and set on saw horses and then look. Bench testing like this is definitive. No guessing involved.
I’ve seen a handful of cracks on undersides, but usually with enough light, you will see external porcelain crack

So, I did as you said and put the toilet on saw horses to examine it. On the side where the water appears, I do see this small crack on the underside. I could not find a corresponding crack on the inside of the bowl. Do you reckon this could be the root of my problem?

I went ahead and replaced the toilet, so hopefully that will solve the issue.

 

[wsween]

Ahh....that could explain it. Korky says that if the top of the flange is 3/8 inch or more below the finished floor, stack two Korky seals.

https://www.korky.com/sites/default/files/2023-09/pk0591_-_6000bp_instructions.pdf section 4d)

Some people with low closet flanges use spacers, made for the purpose. Some put silicone RTV sealant beneath each spacer.

I replied to the other guy but I wanted to let you know as well that I replaced the toilet and put the old toilet (from 1992) on sawhorses and inspected the underside. I did locate this small crack on the underside, on the side where the water was located. I am hoping the new toilet solves the issue.

 

[wsween]

What’s also interesting is this line ends up exactly where the water showed up.

 

[Breplum]

That crack appears to me to only be the decorative skirt part of the toilet, not part of the water pathway.

 

[wsween]

That crack appears to me to only be the decorative skirt part of the toilet, not part of the water pathway.

Hm. The mystery lives on. When I pulled the toilet, I was careful to dry all the water in the bowl, and there was water at that corner, but did not appear to be in the interim. Maybe there was another crack I missed on the underside. At any rate, fingers crossed the new toilet will fix the issue. I’ll give it a couple days and report back.

 

[wsween]

That crack appears to me to only be the decorative skirt part of the toilet, not part of the water pathway.

Well, it’s been a day, and no leak. I’m satisfied. The new toilet did the trick one way or another. Thanks for your help.

 

[Peterson]

Maybe there was some pinhole leak or micro-crack on the underside. That has occasionally happened.

 

[wsween]

Maybe there was some pinhole leak or micro-crack on the underside. That has occasionally happened.

Is it possible that the lining of the porcelain was worn through somehow, allowing seepage through the porcelain?