In article et,
(ScrubsFan) says...

I thought I was clear that I had already done that (poured water into
the bowl) and it ultimately didn't go down, so I manually emptied it.
But for the sake of thoroughness I did it again last night--with the
same results. It hasn't gone down one iota.

OK, then, your next step is either to snake it yourself or call Roto
Rooter. If you want to try snaking it yourself, either rent or buy a
power snake, either pull the pot or climb on the roof with a snake and
garden hose and snake through the roof vent. If the roof is not too
steep, snaking through the vent will maybe save the mess of pulling the
pot. Snake first, then run a hose down the vent after it starts to
drain to flush the lines while you snake some more. If you are very
fortunate, there will be a sewer cleanout just outside the foundation
line. If you unscrew the cap on the cleanout, that may tell you a lot
about the condition of the line. If it's dry, snake back toward the
house. If it's wet, snake toward the sewer. Sometimes the cleanout is
under the house.

Since one toilet is working fine, the blockage is probably somewhere in
the house plumbing rather than the outside sewer lines, but your old
plumbing may join up outside somewhere, and roots could be the problem.
If you have had perennial problems with roots, Roto Rooter is probably
your best bet. In the future, fix your landscaping, use root killer, or
do laundry with Boraxo to keep roots out of the lines.

Before you do anything, plunge it again, since you have tried drain
cleaner. The drain cleaner may have loosened the blockage but not
cleared it. Be sure to use eye protection, you don't want lye in your
eyes. Be as violent as you can manage. The up stroke on the plunger
often does as much as the down stroke. Unfortunately, if the line is
completely blocked, the drain cleaner may not be getting to the
blockage. If the blockage is past the vent, plunging won't do anything,
since the vent will relieve the pressure.



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