59 caravanner black/grey tank renovation

[jeffinwnc]

I love the bath layout of my new 59 caravanner. Tha black tank is above the floor in the corner. I am thinking about adding a new grey/black tank under the floor while I am in the middle of replacing the floor. My idea is under the black tank removing the old dump valve and placeing an elbow (90 degree) then a valve before it enters the new tank. The shower and sink drains would enter the new tank in another location. The dump valve would be on the new tank since it is lower than the black tank. I know this is reversed from normal, but I would like some feedback on this idea.. Thanks so much

[uwe]

Originally Posted by jeffinwnc

I love the bath layout of my new 59 caravanner. Tha black tank is above the floor in the corner. I am thinking about adding a new grey/black tank under the floor while I am in the middle of replacing the floor. My idea is under the black tank removing the old dump valve and placeing an elbow (90 degree) then a valve before it enters the new tank. The shower and sink drains would enter the new tank in another location. The dump valve would be on the new tank since it is lower than the black tank. I know this is reversed from normal, but I would like some feedback on this idea.. Thanks so much

Jeff,
need pics to visualize, and make sure to understand what you're trying to do. Sounds doable, but needs elaboration..

[pbearsailor]

We've got really similar trailers, Jeff, so maybe look at my thread linked below to see what I did with my gray tank. Haven't redone the black as yet, but it'll still be the above floor type in the head.

I'm planning two dump valves on mine. I'd love to do something like what I think you're describing, but I'm hesitant to get away from gravity and a straight down exit for the black tank. I want the black plumbing to be as simple as possible.

That's what I'm thinking, anyway.

cheers,
steve

[markdoane]

I think it would be ok. Keep a few things in mind:

1. Always keep plenty of water in the black tank. The outlet is small (2") and you don't want the elbow to fill up with solids.
2. Instead of an elbow at the discharge of the black tank, put in a tee. If you orient the tee with the mains vertical, you can put a second valve at the bottom and use that as a secondary dump valve. You could use this in case the side outlet & valve to the gray tank gets plugged. It gives you a backup 'straight through' exit.
3. If you mount the gray tank adjacent to the black tank, don't make it very big. Too much weight at the rear of the trailer might reduce the tongue weight.