Odd hole in toilet base

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sdhaber

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Took the tank off to re-build the innards. When I looked into the inlet for tank water, I saw a disintegrating piece of caulk. Removed the caulk and saw this hole from inlet feed to siphon. It was obviously cast with hole and not a flaw. Toilet is from 1998, and I believe it is a Mansfield MPP-160.
Should I re-caulk the hole, or leave it open?

Toilet.JPG
 

djmayhill

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Never seen a hole like that in a bowl before its not supposed to be there someone probably caulked it as a diy attempt to fix an issue
 

Mr_David

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sometimes there are holes for part of the casting process but are usually sealed/plugged before the final firing.
It is very unusual to see a hole filled /sealed with caulk.

I'm going to agree with djmayhill
 

sdhaber

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Folks from Mansfield got back to me:
"The hole is there from when the toilet is made and is a vent hole and is then silicone shut when the piece is graded and boxed. Yes, use 100% silicone and re-plug the hole."

Doug Winters
Technical Support Coordinator
Mansfield Plumbing Products LLC
 

Mr_David

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Still seems odd. I'm going to start looking for this on all Mansfield toilets that I have to pull the tank. Might be a year or 2 before I have to do that. I rarely find the need to reset a tank on a Mansfield toilet. :rolleyes:;)
 

career

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Yep I have the same thing. Peeled back silicone to find a perfect factory hole. Now I gotta wait for silicone to cure.
 

Jeff Handy

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That hole looks too wide to be safely plugged with silicone.
Maybe a rubber bung with silicone around it.
Or something else inert and solid, as a core, then silicone.
 

Jeff Handy

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We would hope it would just piss into the trap way.

The manufacturer could advise.

Meanwhile, it is a $hi++y fix for a design flaw.
There should be a factory plug in there.

Worst case, trap waste could back up into the holding tank during a flush, if the drain had a restriction or clog.
 

simspace

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I found this answer online posted by Mansfield...
That "glob" is a secondary insurance to prevent gas leaks from the sewer. The trap is closed on the inside, but there is a space in between the rim and body. There has to be a vent opening to prevent the bowl from blowing up while it is being fired in the kiln, the "glob" is put on afterwards while it is being graded, otherwise people would think there is a leak there. We are making changes to do this a different way, which is in production already.
 
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