Tank flush issues and leaking underneath




We are getting a massive amount of sewer flies. I have tried putting cleaners in both tanks and flushing them I tried the tank flush hookup today and water just poured out if the bottom of the fifth wheel. Any idea what this could be?

Hi Troy - Two things come to mind that could be the source of this leak.

Since you mentioned you had hooked up the black tank flush when this occurred, it could be possible the connection of this hookup at the tank itself could be broken or leaking, causing the water to pour into the underbelly and leak through the point the drain pipe exits the coroplast.

Another possibility could be the connection of the drain pipe to the black tank has a leak or the valve connection is leaking.

The water in those pics looks clear so I’m leaning towards the black tank flush connection being the culprit as the water probably wouldn’t be clear if it was leaking directly from the tank or drain pipe. :wink:

Depending on your model, you may be able to get eyes on the path of the black tank flush connection to the tank itself from the front storage compartment. Otherwise it’ll require dropping the coroplast underbelly to get a view of the tank and connections to pinpoint the source of the leak.

If you have an endoscope you could use that to get a look at the tank connections from the storage compartment cutouts where the tank valves are located. I have one of these Dual Lens Wireless Endoscope and it’s been extremely helpful in getting a view into hidden areas of the RV.

Good luck tracking this down and let us know what you discover.

2 Likes

We had the same problem. First trip out, and we woke up the next morning to find a pool of black (brown) water on the ground.
I had to take off the under belly panel to access the area around the black tank, and it was a mess.
I found that, during construction, they drilled a screw through the frame of the trailer right into the 3" drain pipe for the black tank.
I won’t even get into the stupid design of the black tank and plumbing on our model (41FLB) but you would think that the guy with the screw gun would check to see what was behind the frame before he/she started drilling.

1 Like

And also our tank flushing water line does not go through to the black tank. When you hook up a hose, water does not go through to the tank. I changed the vacuum breaker valve so the problem is probably where it connects to the black tank. Clearly Vanleigh had issues when assembling their plumbing systems. So I agree with Stuart, your water line could be the issue.

Wondering if you were able to get to the bottom of this?

Excellent troubleshooting steps Stuart.

Apparently the factory never hooked up the black water flush hose. It was just sitting there with a clamp beside it.

Next fix is the lower shower track. Im not sure why they think its a good idea to drill 3 screws in the lowest point. I’ve used silicone but of course that wears off.

Any idea where i can get a bottom 3 track replacement track for the shower? Im going to replace and use a sealant instead.

We’re not fans of the three section glass shower door and notice the some issues you describe. I found this alternative product that’s a retractable self cleaning shower door, Nautilus shower doors .

I got one for the house and have found it to be quite good and easy to install. I’ll be getting one for the RV as well. Considerable weight savings too as the Nautilus weighs about 6-7 lbs compared to the stock glass shower door at nearly 60 lbs.

This guy has a good review of this option for RV shower doors.

The Nautilus Retractable RV Shower Door! (Installation Process & Review)

Just got home from Tishomingo and this is one of the things that they fixed. Whoever did the plumbing at the factory hooked up the vacuum breaker backwards. Probably the same guy that did Troysrq’s plumbing.
So the flush hose line works now.

However I still have issues with the black tank, and it’s mostly due to bad engineering. Our tank drains out the right side of the tank, then the 3" drain pipe has to make a 180 degree turn, back over to the left side of the trailer. Along with the fact that the tank itself is wide and has a low point in the center, it’s difficult to drain everything out of there. If I tilt the trailer to the right to help drainage, then of course that raises the left side so it still won’t drain.
I am wondering if that remote controlled valve is opening all the way. Anyone have issues with that? Of course there is no access to it, so I would have to drop the underbelly panels (or cut a hole) to get to it.