Washroom Sink Drain: Direct To Black Tank

[vincevs21]

My sink drain goes right down into the shower floor drain and directly into the black tank. I haven't used the bathroom at all yet and I don't ever plan to use the shower. I don't have a pee trap on the sink and the drain goes straight to the black tank so I can only imagine that this won't smell nice. I plan to install an outside style shower. How have you guys fixed this up?

[Derek up North]

In my 'ideal world', the sinks and shower would drain to the grey tank, then the grey water would be used to flush the toilet (instead of fresh water).

[linda s]

So does it look like you have only one tank under your RV. When Debbit's tank broke on her 84 Dolphin it was all one piece but internally there were 2 sections. One for the black and one for the gray but separated inside. Pretty sure yours is the same if it's the original tank. National RV certainly made plans so they didn't gas their customers to death.

Linda S

Oh yours is a rear dinette and middle bath. Some Sunraders came like this too like mine. I don't have a sink in mine and I never use the shower either but I do use the toilet and I have never had any bad smells come up from the shower drain. I wouldn't worry about it

[vincevs21]

I have the '83 Dolphin with the rear booth dinette, It has the kitchen sink and washroom on the drivers side. The rear grey water tank below the kitchen sink looks to have been replaced but the tank (unsure if it is split) below the washroom appears to be original with the wires connected to the tank sensor on the rear side. I know there is a grey tank behind the rear wheels and another tank ahead of the rear wheels... I will have to look if there is a drain on the front side as well. I did pull out the floor drain and the tank is white so you can see light in it and was very clean.

[Maineah]

I see what you are talking about the sink just drains into the floor drain there is a P trap in the floor drain so it would not matter if the sink had a trap or not because it does not go directly to the tank. That set up is typical of commercial sinks.

[vincevs21]

No pee trap in this floor drain.

[Maineah]

Well that ain't legal sounds like someone has been at it. It frankly should stink especially if it’s going into the black tank! Open the small drain bung and add water to each drain and see if it comes out of the small valve. But no matter where it goes you kind of need a trap or a real good fan if you expect to use the tanks.

[linda s]

Dolphin tanks from that era were black or marbleized color opaque ABS. If your tank is a translucent white it's a poly tank and someone changed it out and possibly didn't do it right. I'm thinking this is not going to be good

Linda S

[vincevs21]

Looks like the drain has a built in pee trap but it definitely goes into the black tank. No big deal. I can run the drain over and T into the fitting for the kitchen sink on the same side and into the grey. Planning to install and outside shower. I'll add water to the P trap for now.

[zero]

Looks like the drain has a built in pee trap but it definitely goes into the black tank. No big deal. I can run the drain over and T into the fitting for the kitchen sink on the same side and into the grey. Planning to install and outside shower. I'll add water to the P trap for now.

That's a "gully-trap", not a "P" trap. But when you spell out "P" the way you do - it can take on a whole new meaning.