On Mon, 07 Aug 2006 16:53:07 GMT, Speedy Jim wrote:

: QUOTE: "Trying to blast the obstruction out with pressure from a
: hose just backs water up the vent pipe."
:
:That tells you that the vent connection is *not* blocked.
:
:The tub drain likely meanders about until it joins (perhaps)
:the basin drain and finally into the stack. The clog may
:be all the way down where it meets the basin drain at a WYE
:and there could be several 90's along the way.
:
:My point is that these clogs can be very difficult to snake out;
:it takes a professional-sized machine (even a hand-held) to do it.
:
:Often, a common snake will simply go *up* the vent after leaving
:the tub trap instead of continuing down the drain. Very difficult
:to control. A snake with a "down-head boring tool" may be able
:to make it down the drain.
:
:Rent a machine or hire someone...
:
:Jim

Thanks! I think I should add some details. The house is very old (1913).
Very little if any of the plumbing has been upgraded.

Taking a shower in that tub, the water would build up around my feet to
3-4 inches. After a few minutes, after I turned off the water it would
drain away. After a couple more showers, and failed Draino tries (3
one-tablespoon applications), it would take more than 1/2 hour (maybe an
hour or more) for the water to go down. When there was a lot of water in
the tub, the sink drained very very slowly, all of a sudden. I believe
the toilet didn't drain as well as usual, too. Otherwise, the sink and
toilet seemed OK. I believe the sink and tub drain into a large vent
stack that goes down to the ground and up to the roof - a stack about 4
inches internal diameter, and it's attached to the outside of the 2
story house. The tub, however, appears to connect to a 2 inch vent stack
that goes up to the roof and then down through the walls all the way to
the ground, where you can see where it comes out of the wall and angles
into the ground. I presume it joins the 4 inch stack underground.

There was a crew of jack-of-all-trades kind of guys working on the
downstairs bathroom (partial remodel) and I told the guy who I was told
had a fair amount of plumbing experience about the clog in the upstairs
tub. He tried to unscrew the drain fitting in the tub and the cross
piece of stainless steel just broke off instead of the whole thing
twisting out. Then he tries the plunger. Then he gets an AC powered
device out of his truck and hooks it up and tells me to hook up a hose
from out the bathroom window to the hose spigot at ground level and turn
on the water.

After 5-10 minutes he tells me to turn off the water. A few minutes
later he tells me to turn it back on. I wait for word to turn it off and
I hear nothing for 15-20 minutes and start to worry. I run up the stairs
and he's at the top of the stairs giving me the cut-throat turn the damn
thing off sign! I run back down, turn off the water and run back
upstairs and see that the room next to the bathroom has water pouring
out of the ceiling! Panicky, I put 5 gallon buckets around the room to
catch the water and he climbs into the attic and says the water had been
squirting out of the vent pipe, which had a couple of small holes
between the floor and ceiling of the attic. That vent pipe, which had
been within the exterior walls in the 1st and 2nd story, was exposed in
the attic. Luckily, a heat spell was just hitting town, and after 2-3
days, everything had pretty much dried out with the help of a 20" box
fan in the attic and some open windows.

A guy who was helping me last week cut the vent pipe at those holes in
the attic (they are 2" apart in that pipe), saying we could snake the
vent pipe out from where we made the cut (we shoved the portion above
the cut aside, so we could get the snakes down the vent from that
point). He brought a couple we can use to rejoin the two sections of
vent pipe after we are done snaking. He insisted that he was certain
that the vent pipe went straight down to the ground and that the tub
drains into the vent pipe and that the clog was in that vent pipe. Why
else would the snakes not get past 10 feet in that pipe? But when I
measured just how far down the snakes were going, I see that they stop
at a point about 3 feet above where the tub drain pipe could possibly be
joining the vent. At the moment, I can't understand what's going on.