I have a 2014 Sundance XLT 5th wheel. After returning home from a five day camping trip I went to empty the holding tanks. At the campsite, the black tank still showed empty but after the two hour drive home, it showed full. Obviously some paper or stuff on the probe so need to get a good flush. I have my own dump station with water handy so decided to fill the tank before dumping. I used a hose through the toilet to do this. I was watching it with my hand on the shutoff (didn't want to overflow) just as the water was coming up into the toilet pipe just before I shut off the water, there was a loud "pop" sound and the water lever dropped back out of the pipe. I fully expected that something had broken and there would be water on the ground under the trailer. Wrong, nothing on the ground and nothing in the basement area. There was a large bluge in the colopast under the deep (outlet) end of the tank but that was all. Went ahead and dumped the tank and flushed it a couple of times. The tank showed empty and the bulge in the colopast went away so apparently all is well. BUT, what happened with the "pop" and the sudden drop in water level??????????
Blackwater Tank Concern!
- Thread starter SMinter
- Start date
Lynn1130
Well-known member
Several things may have happened here. You may have had a poop pile that cleared or there are metal straps holding the tank in and one or more may have popped loose. There may also be a composite wood platform under the tank that could have cracked. You may want to take the covering off and inspect the tank to be sure. A leak in the lines or a loose tank could be an ugly experience later.
Many here will tell you that the indicators are basically worthless and there are a number of methods for keeping the tank and indicators clean that you can find by doing a search here.
I think you should have a flush connection in the UDC for the black tank and that is the best method for flushing.
Many here will tell you that the indicators are basically worthless and there are a number of methods for keeping the tank and indicators clean that you can find by doing a search here.
I think you should have a flush connection in the UDC for the black tank and that is the best method for flushing.
According to my dealer, there are no straps. He says the tank flanges just set on the frame rails. The underside is covered so it is not easy to see the tanks. Would need to remove the bottom covering and hate to do that if there is no problem. Just don't understand the pop and sudden drop in water lever and bulge. It is occurred slowly while filling I would not be concerned but this was sudden. Not sure where I could put angle iron to support the tank. Can't tell where the frame cross members are.
I want to add, I have no concern about the indicators. I understand the problem with them and generally can keep them working well enough to get by. The installed flushing system is great for flushing out the tank to get all the solids off the bottom but it does nothing for the upper indicators. That is why I fill the tank at least 3/4 full before dumping to clean off the sensors. If that doesn't work, I put in some Dawn and some Calgon and fill and then drive around. Then I dump and that has always done it. My concern here is the integrity of the Black tank.
danemayer
Well-known member
I don't know about the tank configuration on your Sundance, but on our Landmark, the black tank is above the gray #1 tank, with some offset front-to-rear. If my black tank expanded, it could put downward pressure on the gray #1 tank, possibly stressing the pvc pipes that go into the gray tank.
Also, on our Landmark, there are cross braces attached to the frame members and the Gray #1 tank sits on those cross braces. There are also straps. Downward pressure on the tanks could have sheared the screws holding the cross braces to the frame.
The only way to check these things would be to 1) take down the rear wall of the pass through storage area in the basement, and 2) drop the coroplast to check how the tanks are being suspended.
Also, on our Landmark, there are cross braces attached to the frame members and the Gray #1 tank sits on those cross braces. There are also straps. Downward pressure on the tanks could have sheared the screws holding the cross braces to the frame.
The only way to check these things would be to 1) take down the rear wall of the pass through storage area in the basement, and 2) drop the coroplast to check how the tanks are being suspended.
Both my tanks (gray and black) are under the floor of the basement area. Black is at the front and gray is behind it. They sit crossways between the main frame rails. Dealer refuses to do anything and I sure am not into dropping the colopast. Guess I will proceed normally until something happens. When I get it back home, I will fill the tank again (with clear water) and take it on the road to make sure everything is OK. Would rather have the tank fall out with clear water and close to home than at some other time.
Silverado23
Iowa Chapter Leaders
If you really wanted to do an inspection but did not want to fully drop the coroplast, You remove a few of the screws on one edge and use a camera to investigate. If you cannot reach the area well enough with a regular digital camera, You could rent an inspection camera scope that has a flexible tube to reach distance areas.
You could also purchase one that may work too.
http://www.harborfreight.com/Digital-Inspection-Camera-62359.html
You could also purchase one that may work too.
http://www.harborfreight.com/Digital-Inspection-Camera-62359.html
