New Bathtub drain causing toilet to gurgle, drain slowly

[Jason B]

Hi, this one has me a little stumped - any help is appreciated.

I recently replaced a bathtub and toilet as part of a full room overhaul. I replaced the toilet first and noticed a dripping sound coming from the pipes underneath. This did not happen with the previous toilet, but I chalked it up to differences in toilet design, etc... I don't know if this will be relevant but thought I'd mention it.

When I connected the drain and tested it, the toilet immediately began gurgling and is now very slow to drain when flushed - it wells up and drains out over the course of an hour or more. The tub drain is also very slow, but not clogged, at least completely so. A slow drip (similar to the toilet's drip) can be heard in the main stack for a long time after the tub has been turned on for a short amount of time.

I'm dealing with a drum trap for the tub that is partially embedded in the wall, so I don't believe replacing it is an option. Just after the drum is a tee going up into a vent that is definitely the tub vent, and may also be a vent for the toilet (I can't tell, as the pipe going down off the tee goes into a wall and into the finished basement.)

I've included a diagram to hopefully show the setup a little better. The only thing I can think that might be causing the slow up is the height of the tub drain. It is within an inch of the previous setup, but that bump up puts it higher than the top of the drum. I can't find much on drum traps, as it seems they've been done away with. Is that something I could look into?

Thanks for any help you can offer!

Jason

 

[Reach4]

I am not a plumber. The symptoms sound like a blockage at or after the toilet. I think you need to lift the toilet, and clear out downstream.

For the drum trap, try to clean it out. It is not causing the toilet symptom, but they are made to be cleaned out. There will be a lid which you unscrew ideally, but that you often have to mangle and replace to get in there.

 

[Sponsor]

 

[Jason B]

I am not a plumber. The symptoms sound like a blockage at or after the toilet. I think you need to lift the toilet, and clear out downstream.

For the drum trap, try to clean it out. It is not causing the toilet symptom, but they are made to be cleaned out. There will be a lid which you unscrew ideally, but that you often have to mangle and replace to get in there.

Interesting. I'm going to try that tonight.

Any idea why the toilet drained well prior to the tub drain being hooked up? Just curious at this point.

 

[Reach4]

No.

If you keep holding down the flush lever or do continual flushing (watching that you don't overflow the rim), does water rise into an empty tub? Does the supply stop to the toilet work well? If not, you may want to replace that valve with a good 1/4 turn valve.

If you keep adding water to the tub, does the toilet water level rise?

 

[Jason B]

No.

If you keep holding down the flush lever or do continual flushing (watching that you don't overflow the rim), does water rise into an empty tub? Does the supply stop to the toilet work well? If not, you may want to replace that valve with a good 1/4 turn valve.

If you keep adding water to the tub, does the toilet water level rise?

The supply line should be fine, I put in a new quarter turn valve about a week ago. No issues with leaking/dripping there.

When I overfill the toilet, I hear air escaping out the tub drain, and the toilet gurgles when I use the tub drain, but the water level stays the same in both when the other is used.

 

[BillTheEngineer]

Sounds like the vent line is clogged

 

[Reach4]

Sounds like the vent line is clogged

If so, then two clogs-- because a clogged vent is not going to make the toilet not flush.

 

[Jason B]

Thanks again for the help guys.

It sounds like this is a clogging issue more than my bigger concern, that a change in the height of the drain opening in the tub from even with the top of the drum to slightly above would cause the slow down. I'll take cleaning out the lines over re-configuring them!

In hindsight, when I pulled the t shirt I had plugging up the toilet flange during the reno out, some debris did fall in that had gotten stuck inside the rag. Sounds like that could be the culprit. If that doesn't work I'll see about getting the drum cap off, but I'm not too optimistic that is going to happen.