Turned on black tank flush, may have left it on a bit too long

[sws4420]

In the spirit of this thread, (http://www.keystonerv.org/forums/showthread.php?t=7134) I have a quick question to those of you that may be in the know. (I didn't want to bump an old thread, as I know that it a sin on some forums.)

Let's assume some idiot turns on the black tank flush on a Sprinter, closes the drain valve because he loves to fill the tank and watch the sludge rush past the transparent fitting on the drain line, and gets sidetracked. While the idiot is away from the filling tank, his wife hears a popping sound and now when the tank gets full, there's a foul smell coming from under the unit. This particular idiot hasn't taken the bottom of the unit apart to look at it yet, as he's mildly afraid to. I found the attached diagram somewhere on here and I'm encouraged that hopefully it's something easy.

Any thoughts? Any help is much appreciated.

[rode2nowhere]

Wow the underbelly, does it ever drip water or anything from under it?

[sws4420]

Yeah, I can get it to drip when I fill it from the top, but it has to get pretty full for it to drip. That leads me to think it may be one of those hoses popped off or at least cracked. The tank still gets water into it when I flush it, but hard to tell if it's the same volume because the unit is still pretty new to us. We have the Polar package on it with the enclosed underbelly, I'm planning on taking the enclosure panel down tomorrow to take get a visual on what's happening under there. Cautiously optimistic that it may be an easy fix.

[rjsurfer]

I had something similar happen to me and it turned out to be an "easy" fix.

I too had dripping from the drivers side Coroplast underbelly when the tank was full and when flushing the tank.

I cut away a bit of the Coroplast where I heard the dripping and shined a flashlight up into it and found the spin on flush water connection loose. It sits about half way up the tank and I just spun the connector tight, it took a few turns and it was fixed. Some Gorilla tape fixed the small slit I made.

Hopefully you will have the same luck.

On re-reading your post I didn't hear any popping sound, so your results may vary.

Ron W.

[sws4420]

Thanks Ron. Wish it was that easy.

I tore down a bit of the Coroplast today and was optimistic, as I located the flush connection pretty quickly and easily. Everything looked good. I turned the flush on to see if there was anything wrong there and there wasn't a drop. So I had my son step on the toilet flush valve for a number of minutes and finally there was a leak coming from the topside of the other side of the tank. I'm unsure what it could be, honestly. I'm hoping I can find a diagram of the tank or even a picture of the tank. I assume there's a vent, but I'm unsure where on the tank that is. I went from being hopeful to pretty upset with myself. I can't imagine a replacement of the black tank is easy enough to do myself or cheap enough where I could just laugh it up to a stupid mistake.

Do any of you guys know if there is any sort of opening on the topside of the tank? I haven't looked, but maybe the leak is from where the toilet connects into the top of the tank? I'm at a real loss for information.

[Bob Landry]

I would say that particular idiot ignored the sticker by the tank flush hose connection that says the valve has to be open when flushing the tank.

[sws4420]

Ouch. Right in the ego.

Point taken, thank you.

[TandE]

I say get a mirror an try to look at the top of the tank about where it is leaking from. Or better yet a remote camera snake thingy.

I'm not entirely positive but I didn't think using the black flush valve would crack a tank with the drain valve closed. Even if you over filled it. The way I see it it would all just vent out the vent tube or even the toilet itself before it built up enough pressure to crack a tank. But since the toilet is sealed most likely the vent tube. I could be way off though but that's how I see it right now.

Are you sure the tank wasn't cracked higher up than you have had the level before? Or even if the toilet pipe into the tank is cracked or a bad seal? Or even the vent tube?

[Bob Landry]

Ouch. Right in the ego.

Point taken, thank you.

LOL.. I just couldn't pass that one up. I feel your pain.

Check around, there are repair materials for plastic tanks. You may have to drop it to find it, but it may turn out to be a crack or split that's an easy fix.

[sws4420]

I say get a mirror an try to look at the top of the tank about where it is leaking from. Or better yet a remote camera snake thingy.

Are you sure the tank wasn't cracked higher up than you have had the level before? Or even if the toilet pipe into the tank is cracked or a bad seal? Or even the vent tube?There isn't any clearance over the tank to see the topside of the tank, so I may have to drop the tank to see where exactly the leak is coming from. Definitely the top of the tank somewhere.

The unit is barely a year old, so I wouldn't be comfortable knowing there may have been a crack when I took delivery. The tank leaks before the material reaches up the neck of the toilet, so I don't think it could be that high either. (That's how I used to know my tank was full on my last unit as the sensors didn't work one bit)

LOL.. I just couldn't pass that one up. I feel your pain.

Check around, there are repair materials for plastic tanks. You may have to drop it to find it, but it may turn out to be a crack or split that's an easy fix.Not a problem. I have big shoulders. (tx)

[JRTJH]

Before you start thinking about pulling the tank, as stated earlier, it's unlikely you split the tank (possible but unlikely). The toilet has a rubber ring (similar to the wax ring in home toilets. That ring is soft, foam rubber and can be easily displaced. At this point, before going too far, remove the toilet, check that ring and see if it may have been pushed aside by the water pressure as the tank was filling. If you haven't seen any poo on the roof and the vent stack is intact, then you may well just have a leak at the toilet ring. Checking that is a 30 minute job (get a new ring before you start) and is much MUCH easier than trying to drop the black tank to see if it's damaged.

You may eventually wind up dropping the tank, but from the symptoms you stated about leaking only when your son stepped on the flush valve inside the RV, I'm thinking (hoping for your sake) that it's probably associated with the toilet to tank union. That foam ring is the only common link and the tank is supported there and is thick enough in that area so that it's unlikely to split in that location. And, if the black tank is empty, flushing the toilet would not provide enough water to fill the tank and overflow from a split anywhere except along the bottom of the tank. The flush hose running into the tank should also show a leak along the bottom relatively fast, so the bottom of the tank is probalby still sound. Good luck :)