black water exit pipe sealed!?
I have a mystery to solve and am looking to the wise ones out there.
My recently purchased '66 Overlander project came without a dump valve on the black water exit pipe. There was a toilet but the trailer had not been used in quite a while. I removed the toilet. There had been steady eakage at one time and the plywood was rotted around the toilet base. This had seeped backdown to and greatly rusted the rear L bracket support for the tank which I need to replace.
I wanted to make sure the tank itself did not leak so I put plastic over the outlet, secured it and filled the blank tank. The water did not leak from the tank, which was good and when I removed the plastic to drain out the tank, nothing came out! The water was standing still. I felt the exterior of the exit pipe and it is sealed. I felt inside the tank to where the exit hole should be and it is smooth. It certainly looks like a vintage tank but again, when I felt inside for the exit, the sides were very smooth and there seemed to be no buildup of any waste so possibly it was a replacement tank. Okay. If so, at least in this case I guess one has to cut the hole open at the exit?
The photo below is a closeup of the exit housing minus the dump valve which did not come with the trailer. It looks patched from the inside and sealed (it slightly leaks) so I expected to find a corresponding patch on the inside. I could only feel a smooth wall where the outlet should be. Easy enough to cut out and install the appropriate dump valve but I am sure puzzled as to what gives. Any ideas?