Water Draining out of Toilet Bowl

[Jerry]

The water in our toilet bowl slowly drains away when toilet is not in use. It takes about two hours for the water to disappear. Also, when flushing, it makes sort of a loud gurgling sound. I have checked the air vent from the roof and also run a snake down the bowl. No change. Any ideas on cause and remedy? Thank you.

[DIY Guy]

The vent was my first thought. A clogged vent line allows a suction to develop which would pull the water out of the bowl.

The next thought was a cracked bowl is allowing water to leak out. And worse, it may not be going down the drain, but into the surrounding area.

Off the top of my head, those are the only two reasons I can think of. Let us know what you find out.