The 5th Wheels similar to yours I've worked with have two black tanks. I assume you are talking about the forward head (bathroom) that is not working? Toilets in RVs are typically directly above the black tank. In the case of your forward head, there is a short piece of pipe that spans the distance from the tank to the floor where the toilet sits, this can usually be accessed by pulling the wall panel inside the storage compartment under the head area. Not much distance from toilet to tank for waste to travel. You say it's plugged, I assume because you can't get waste to go where it's suppose to. Let me give you another area to consider. These tanks are (obviously) sealed, when the toilet has water, that pipe is effectively sealed also. This is one of the reasons you have a vent pipe. If the vent pipe (that goes from the tank straight up through the roof) is plugged up, you will have a tank that will not allow waste. It becomes air locked. Maybe my ramblings here help a little, I'm curious to hear what you find.
|