After very little searching I found the source of my plumbing leak, but am confused about how I should fix it...
'91 Warrior
Underneath the shower pan I can see two drain pipes descending into the grey water tank, one presumably from the kitchen sink and the other to drain the shower pan. When running the sink, I can hear water draining into the grey water tank no problem; however, when I run the shower about 100% of the water going down the drain (and down the pipe connected to it) comes up around the outside of the drain pipes, flooding from the square cut-out in the floor that pipes pass through to the grey water tank.
Grey water tank is nearly empty, so I don't believe that is the culprit. The shower pan drains completely, and the other drain pipe for the sink works well.
Does anyone know how these drain pipes connect to the grey water tank? i.e. is the connection threaded, glued, compression fitting, passive v. check valve?
Seems like I have to drop the grey water tank, in any case.
Any insight is greatly appreciated.