Hi,

I just changed a toilet bowl due to a pinhole leak - the water level drops overnight.
I 've learnt my lesson so I installed the second toilet bowl in my garage on a flat surface, slowly added some water and... the water level still drops.

Question: Is the toilet bowl S trap suppose to be glazed all the way to the waste horn ?

Thanks

It depends. If it's an older toilet that used 3.5 gal. for flushing; that is, the toilets made before the EPA rules, most likely would not have a fully glazed trap. The older ones had enough flushing pressure with the 3.5 gal that the traps didn’t need to be fully glazed. The new toilets that use 1.6gal. Were redesigned so they flush better with less water and part of that redesign included fully glazed traps, at least on the American Standard and Kohler units that I looked at (opted for two American Standards). I can’t say for certain, but I would suspect:confused: fully glazed traps are common on new toilets since the first 1.6’s didn’t flush for s***. :(