Toilet doesn't flush while tub is draining

[Eric M]

I've got a problem I'm stumped by and would appreciate any ideas.

I've got a full bath behaving oddly: The toilet works fine generally, flushes strong and has handled a decent amount of use (dinner parties, etc) with no trouble.

The tub in this bathroom doesn't get used often but I recently noticed that when the tub is draining the toilet won't flush (the bowl just fills up and very slowly drains). My first guess was that there was a clogged pipe downstream of the toilet but now I'm not so sure.

Some more info:
- The tub drains very slowly itself. Maybe a gallon a minute or less.
- I tried snaking at the toilet with a 25' snake. Got nothing and it didn't seem to make a difference.
- I tried snaking at the tub. No good.
- I tried liquid plumber in the tub. No impact.
- I tried running water into the tub for a few seconds (just to fill the drain line) then flushing the toilet; its not quite as bad but doesn't flush well. So it doesn't seem to be purely an issue of a large volume of water getting backed up but something else.

I suspect the issue _might _be the vent but I'm not sure how to diagnose or get at the vent, or if I'd see such a slow drain with a vent issue.

What should I do next? Longer snake? Something else?

Thanks!

 

[Nolan]

One thing you could try if you think it is the vent, is finding the vent on the roof and looking into it to see if anything has gotten in there to clog it up

 

[Sponsor]

 

[Reach4]

Pretty odd. Let us know what fixed it when that happens.

Regarding the tub drain, see https://terrylove.com/forums/index....b-difficulty-with-shaft-in-overflow-tube.889/ Did you pull the linkage and snake through the overflow?

I think I would call a drain cleaning specialist.

I am also thinking that you could benefit from a more recent toilet if you ever get a clog or slow flush when you are not draining the toilet.. They have gotten better.