oreo123 wrote:
There has never been any garbage run ito this. Since we tried it a
week ago
there has been a total of maybe 8 gallons of fresh water run into it.

My thinking is its either the slope of the pipe under the finished
floor. Or
its something vent related.

I need someone who really knows venting and plumbing to make an
educated
call on this. I want to go the least destruction way possible.

TIA.

I'm not a plumber, nor did I sleep at a Holiday Inn last night, but I
can tell you how I'd approach it. I think that the couple of gallons
draining before it backs up needs to be investigated - the exact volume
will give you a better indication of where the blockage is occuring. I
did a rough calc using 2 gallons and came up with ~22' (assuming a 1.5"
line). I'm sure the line isn't bone dry due to the blockage, so it
could be further along. Maybe that 25' isn't quite enough

R