Slow / No Draining Toilet

[adolloff]

Hello--- we have a 1955 ranch. We've never had a working half bathroom (toilet always slow to drain). I finally got around to replacing the toilet, and it still does not flush properly. The toilet drains directly inline with the rest of that side of the house (kitchen sink and half bath sink). There are what appears to be two vents---- one at the kitchen sink and one at the half bath sink. Attached is a diagram of the plumbing layout, and the photo is where the toilet meets the main drain pipe for that side of the house (basement joists). Any advice as to why I'm having so much trouble with the toilet? Do I need to add a closet bend or something? Thanks!!

 

[JackGalvin]

Are there any antivac traps on the kitchen and bathroom sinks??? If no this is your problem possibly....

 

[adolloff]

Both sinks have traps

 

[JackGalvin]

Yes but do they have air admittance valves on them?

 

[JackGalvin]

If everything else on that side of the house drains away and you are absolutely sure of no blockage the problem is caused by air Compression and lack of inlet air due to pipe configuration or no anti vacume traps on other appliances

 

[JackGalvin]

Hit the vents with a hammer they are probably stuck in the closed positiom

 

[adolloff]

There are stack vents so I don't need the interior ones. This doesn't seem to be a venting issue.

 

[phishfood]

I would start by having the 3" or 4" drain line snaked or jetted to completely restore the inside diameter of the drain line. Once you have made sure that the main line is completely open, then you can address possible venting issues.

 

[adolloff]

They were snaked about a year ago, with no change in the flushing afterwards.