Toilet Bowl Drips water back down into sewer pipe

[Jaybird34]

Hello,
I have a mind twisting question that i really hope you guys can help me with.
I have a toilet that is constantly dripping water from the bowl down into the sewer pipe, its like it creates a suction and pulls the water out of the bowl.
You can hear the water dripping drown into the pipe. I thought it was the flapper so i changed it out, this didn't fix it.
I went and bought a new toilet, installed it but still the same dripping water out of bowl into sewer pipe happened with it also.
I have even ran a 50' snake down my vent from up on the roof but still didn't help.
This toilet is located in the master bedroom and there is another toilet connected to same line just across form it in a guest bathroom, these are upstairs in a split level home. The down stair toilet is fine.

all lines seem to be clear the toilets flush fine and go down fine, except for the constant dripping.

I would greatly appreciate any ideas.

Thanks,

 

[Jadnashua]

It's unlikely the old and new toilet had leaking flapper valves, but it's possible. Shut the water supply off and let it sit overnight or maybe while you're away at work. Check the level and see if it has dropped. That, at least, will eliminate the flapper valve as a source.

Note, that plastic piping expands and contracts with temperature changes, and if it is rubbing on something, can make a ticking, or click sound, that can sound like a drip. If the pipe is next to a heat duct, it could just be the drain line moving with the heat of the duct as the furnace turns on and off.

 

[Sponsor]

 

[Jaybird34]

OK i will try this and post back.

 

[Jaybird34]

Well, I finally Tested the toilet. It appears that the toilet does drip water from the tank. I turned the water supply off & also dropped some food coloring into the tank and seen the colored water in the bowl.
This has been a weird problem, because i have changed the entire toilet out and it was still dripping water out into the toilet bowl & into the sewer lines.
So my question is what would you guys recommend next for me to try. I should definitely changed out the flapper assembly first so i know I'm getting a good seal? what is a good flapper assembly to purchase? whats the best?? I have another toilet that has a different style flapper, its round in shape and picks straight up when flushed. the toilet in question has the traditional style flapper.

Lets say I change out this flapper and if i still hear the dripping of water out of the bowl into the sewer line and I'm also not losing any water out of the tank, what could be casing this to happen.

Thanks for the help

 

[WJcandee]

It's hard to beat a Korky flapper. Take a look at the options in the red chlorazone material at www.korky.com

Korky invented the flapper and makes the original equipment flappers for many brands of toilets, including Toto, right here in the US.

That basic black Korky flapper also usually works great. Run a little brillo around the mouth of the flush valve to make sure there is no debris on there preventing a good seal. And don't use in-tank bowl cleaners because they degrade the flapper and such.

And, before you do anything, make sure that the refill hose from the fill valve is "daylighted" on a clip above the rim of the overflow riser. If it's just stuck down in there, it can siphon water from the tank through the fill valve and down the overflow riser and into the bowl, giving the appearance of a slowly-leaking flapper when it's really a siphon of the tank water.