Black tank issues .........

**piper guy** · 10-17-2018, 07:27 AM

Ok, need some ideas and maybe suggestions from those who have gone there before me.

All of a sudden we've got some black tank odors in the coach. Most noticeable at the vents that are under the steps and under the entry closet.
Our coach is a 2013 36RL. Never had any issues before.

So - here's the question - I'm going to do some investigating tomorrow. Should I drop the belly pan (will be a major pita in the position the coach is in right now) or cut an access panel and then put it back up with Gorilla tape? There is a slight belly visible in the belly cover so I'm thinking that I may have some "fluids" in there. The other thing is that I'm not really sure of the tank layout in there. Is the black above the greys ? Where should I look for possible issues and shoul I take the belly pan off after draining or cut a larger access hole ?

Thanks in advance guys, I'm hoping this may be something simple

**hoosierguy** · 10-17-2018, 02:17 PM

Quote:

Originally Posted by piper guy

Ok, need some ideas and maybe suggestions from those who have gone there before me.

All of a sudden we've got some black tank odors in the coach. Most noticeable at the vents that are under the steps and under the entry closet.
Our coach is a 2013 36RL. Never had any issues before.

So - here's the question - I'm going to do some investigating tomorrow. Should I drop the belly pan (will be a major pita in the position the coach is in right now) or cut an access panel and then put it back up with Gorilla tape? There is a slight belly visible in the belly cover so I'm thinking that I may have some "fluids" in there. The other thing is that I'm not really sure of the tank layout in there. Is the black above the greys ? Where should I look for possible issues and shoul I take the belly pan off after draining or cut a larger access hole ?

Thanks in advance guys, I'm hoping this may be something simple

Vaughn,
It is my understanding that there is a Hepvo trap under the bathroom vanity sink and the kitchen island sink. Those drains are connected to the grey water tanks. And yet, when I back flush the black tank, I occasionally get black tank odor back into the bathroom. That has been a puzzle to me because it is not supposed to be connected to the black tank. It has not been severe enough, so far, for me to dig into the issue. But, I would suggest checking out those Hepvo traps. Here is a link to info on Hepvo vent:

https://blog.wavin.co.uk/why-choose-...plumbing-trap/

The other possibility would be the roof vents. Make sure they are not plugged by wasp nest or other debris.

Relative to the coreplast underbelly cover.........I have found that it tends to belly down some between support screws. If you do want to drop the coreplast under the black tank, start removing screws from the drivers side (left side) of the coach, but, leave the passenger side screws in place. That keeps the coreplast aligned so it is much easier to put back in place. The coreplast will drop down enough so you can examine the tank for any leaks.

Hope this helps and good luck.

Guy

**piper guy** · 10-17-2018, 04:35 PM

Thanks Guy, I had forgotten those. In this instance though, especially after talking to Chris, I think I've got a black tank valve seal that's failing. The tank got quite a bit fuller than usual just b fore this dumping and we're thinking some "effluent " leaked out around the seal. It's much better this morning but still an odor if you stick your nose down by the vent under the bedroom steps. Chris said his failed about a year ago and since his coach is a 2012 that would make me about due. Lol

Decided that as soon as it clears up a bit (it's actually raining it's butt off here in the high desert) I'm going to crawl under, pick the lowest part in the coroplast, and cut about a 1" hole with a drain pan under it and see if there is any liquid. In any case I'm going to order all three dump valves and just plan on replacing all while I'm in there.

**piper guy** · 10-17-2018, 09:39 PM

Pretty sure I've got a black tank gate valve going bad. I know that one is a 6' cable.
Does anyone happen to know what length I need to order for the Greys ?

**hoosierguy** · 10-17-2018, 11:03 PM

Quote:

Originally Posted by piper guy

Pretty sure I've got a black tank gate valve going bad. I know that one is a 6' cable.
Does anyone happen to know what length I need to order for the Greys ?

I replaced the black tank valve 2 years ago with a Valterra valve and 6 foot cable. I filled the cable guide with Teflon lubricant before installing and it operates very easily and smoothly. I put some silicone grease on the valve seals.

I looked at the grey tank valves and decided to have someone else replace those two valves. They are in a location that is very difficult to reach and work on. You may have to buy the 6 foot cables and cut to length.

Good luck.

GA1817 · 10-18-2018, 04:37 PM

Vaughn I would not cut it at all. Start at the corner where the waste pipe exits the corner of the coreplast cover. If you remove screws in both directions you can shine a light in there as the waste valve is within three feet of the corner. Keep in mind that it is only a friction fit between the pipe coming out of the slip hub into the opening of the black tank. There is some plumbers putty around the seam of the at where they meet and you will likely find a SS pipe clamp over the black tank opening. That may be the source of your seepage. To fix mine I put a new slip hub on another section of pipe I purchased and prior to inserting it into the tank I purchased a rubber boot with two SS clamps that added additional protection against seepage. It has worked quite well. I iwl add pics in a minute.

GA1817 · 10-18-2018, 04:39 PM

This is my replumb job with two new slip hubs, a new section of pipe (white pipe), a new valve, and a rubber boot with two SS clamps. One of the grey tank valves can also be accessed with the corner of coreplast taken down. It is near the side of the camper wall but is somewhat high and difficult to get to. The second valve must be under the coreplast past the drop down section of the frame (back towards the kitchen).

GA1817 · 10-18-2018, 04:49 PM

Vaughn,

I purchased the following valves from Amazon. The 1-1/2 inch grey valves are in the drop down selection. No cutting of cables is necessary.

https://www.amazon.com/Valterra-TC37...70_&dpSrc=srch

**piper guy** · 10-18-2018, 06:42 PM

Dean - many thanks ! I'll get the same setup ready to go with a new valve.

**piper guy** · 10-18-2018, 06:49 PM

Does amazon have the slip hubs also ?

GA1817 · 10-18-2018, 06:52 PM

Yes they do. I actually have 4 spares. I ordered through E trailer and paid for 2 day expedited shipping on a Saturday morning only to find out later that afternoon they would not arrive until Thursday of the following week. I was livid. Got up Sunday morning and went to Amazon, free shipping with Prime and received them on a Tuesday

!

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

travelin' texans · 10-19-2018, 11:14 PM

Vaughn,
DO NOT cut those valves out, there's no slack or extra piping to put them back. Once you cut it apart be prepared to completely replumb from beginning to end black & grey or at least get VERY creative with plumbing. Just changing the slide gates with new seals can be challenging with no slack in the piping.

**piper guy** · 10-20-2018, 05:06 AM

Yeah, I had already come to that conclusion. Just gonna replace the valve

Elliott & Vicky · 10-27-2018, 05:23 PM

I have learned if you remove the corroplast, when you are putting it up, fasten one end and block a 2x4 across it about a foot from the end, put in more screws, move the 2x4, etc. makes it rather easy.

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