|
Mystery Black Water Tank Leakage
I decided to replace my Black and Grey water tank drain system with a Valterra output. I use a Macerater Pump on occasion and the existing Thetford coupling with adaptor was not strong enough to hold the Pump without leaking. The main "Y" fitting is readily available from Valterra which makes it an easy modification. I also decided to replace the Black water Tank valve since I have always had a small leak there. I perodically would tighten up the steel band to stop the leak. When I removed all of the plumbing I discovered the reason for the leak. The Valterra valve flange fits into the tank and is clamped so that it can be replaced if necessary. I had considerable difficulty in removing the valve flange and discovered a strange "U" shaped dip in the flange. I also removed considerable caulking from around the flange. The input to the Black Water Tank was too small and the new flange would not fit. It was off about 1/16 of an inch. Using a cylindrical plane I ground some material from the tank input until the flange was a snug fit. I attached the band and tightened it resulting in no future leaks. Mystery solved!! Airstream also found that the flange would not fit and there solution was to take a hot iron and put a "U" shaped bend in the Valterra valve input flange so it would be smaller and thus fit the tank. That is why they packed the joint with caulking compound. How do I know Airstream did this? The entire joint and caulking was neatly painted in Airstream grey. This must have been a problem with all of the Classics that used the same tanks. So if you have had a small Black Water tank leak where the valve is attached to the tank this is probably the answer.
|
Linear Mode
