Community Forums

HackMan162 · 01-14-2021, 03:51 PM

Hi There,

My wife and recently acquired a 2012 CanyonStar 3920 in incredible condition. It has the half bath option in the garage.
Our maiden voyage was to an RV Park about 20 minutes from home that we lived at for about 3 weeks while having some remodeling done at the house. We love it and are looking forward to a lot of trips coming up!

Issue I am having is black tank dump. The first time I dumped it, after 7 or 8 days, everything seemed to be fine. A good amount of "stuff" came out, followed by a gray tank dump. I close the gray valve a couple days before the planned black dump to get a good amount of shower water to dump and flush.
The next time I went to dump the black tank, not a lot of stuff came out, at least as far as I could remember versus the first time. That had me wondering if I was missing something and if there was a second dump port for the half bath. I called Newmar and asked, and they assured me there is only a single tank, with one dump valve. The half bath has a macerator toilet in it.
Oh yeah, the sensors have read full since we got the coach, so they are no help.
Anyhow, fast forward another week, we dumped several pots of boiling water down the front toilet, made sure to use a lot of water, and when I went to dump the tanks, again, not a lot of "stuff" came out. So now we have been at home a little over a week and I am ready to try to figure out what next.
I am thinking of dumping a 20lb bag of ice down the front toilet, then driving around a bit, and heading to a dump station.

Any other ideas? Sorry for the long thread...

hattitude · 01-14-2021, 04:57 PM

When you dump the black tank do you use the "sewer flusher" otherwise known as the black tank rinse...???

Here's the pic from my 2014 3920...

HackMan162 · 01-14-2021, 05:33 PM

I did the first 2 times. The last day I was doing this in freezing rain, so didn't spend any time using it. That is planned for my next step...
Any other advice is greatly appreciated.
Are your sensor somewhat accurate?

hattitude · 01-14-2021, 07:11 PM

Quote:

Originally Posted by HackMan162

I did the first 2 times. The last day I was doing this in freezing rain, so didn't spend any time using it. That is planned for my next step...
Any other advice is greatly appreciated.
Are your sensor somewhat accurate?

My 3920 sensors are very accurate....

The sensors on my old toy hauler trailer were worthless (they were internal to the tank, unlike my Newmar sensors).... and that trailer didn't have a black tank rinse.

I bought one of those rinse wands that rinses out the tank, via the toilet. I flushed that tank real well one time... That rinse wand loosened up a bunch of crap (literally), plus, the sensors started working ... it taught me the value of rinsing out the black water tank while dumping...

rlott2k · 01-14-2021, 10:14 PM

We bought a trailer that had a similar situation. There was 1/2 a towel in there. It would float over and cover the exit.
Our Kountry Star lasts us 2weeks if we are careful, perhaps it’s just not full?

Govols46 · 01-17-2021, 06:09 AM

There’s a guy on you tube (T R Bowlin) who recommends Borax & Dawn dish detergent- his vid goes into lots of detail about black water tank issues. His theories sound good, but I’ve not tried it yet.

PandS · 01-17-2021, 07:11 AM

Ice cubes won't do anything.

https://www.youtube.com/watch?v=iH6acEmqvcw

If you are stationary for a long time, fill the black tank with clean water and let it soak overnight. Then, use the black tank rinse while dumping that water in the morning. I do this if we are going to be in one place longer than a week or so.

When traveling, as long as I know we will be hooking up in a campground with full hookups, I put 1/3 to 1/2 tank of fresh water in the black tank and let it slosh around while we drive down the road. There is always a bunch of "stuff" in the previously clean water when I dump it. Both of our toilets are the macerator type.

We had a professional outfit to pressure wash our tanks once. After watching, I bought the hose and fittings needed and a portable pressure washer and now do it myself every 5-6 months.

https://www.youtube.com/watch?v=5YW7AsVr3Jc

As you can see in this video, the grey tanks also accumulate a lot of "stuff" (called struvite).

Your sensors are probably reading a build up of "stuff" stuck to the walls of the tank. Ours start to be unreliable when this happens. The procedures I listed above will help to get them working again.

Hope this helps. - Paul

Tigerfan1 · 01-17-2021, 08:40 AM

Quote:

Originally Posted by PandS

Ice cubes won't do anything.

https://www.youtube.com/watch?v=iH6acEmqvcw

If you are stationary for a long time, fill the black tank with clean water and let it soak overnight. Then, use the black tank rinse while dumping that water in the morning. I do this if we are going to be in one place longer than a week or so.

When traveling, as long as I know we will be hooking up in a campground with full hookups, I put 1/3 to 1/2 tank of fresh water in the black tank and let it slosh around while we drive down the road. There is always a bunch of "stuff" in the previously clean water when I dump it. Both of our toilets are the macerator type.

We had a professional outfit to pressure wash our tanks once. After watching, I bought the hose and fittings needed and a portable pressure washer and now do it myself every 5-6 months.

https://www.youtube.com/watch?v=5YW7AsVr3Jc

As you can see in this video, the grey tanks also accumulate a lot of "stuff" (called struvite).

Your sensors are probably reading a build up of "stuff" stuck to the walls of the tank. Ours start to be unreliable when this happens. The procedures I listed above will help to get them working again.

Hope this helps. - Paul

Could you post what fittings you purchased. Thanks

PandS · 01-17-2021, 08:49 AM

Quote:

Originally Posted by Tigerfan1

Could you post what fittings you purchased. Thanks

Check out post #26 in this thread:

https://www.irv2.com/forums/f103/how...-491083-2.html

PandS · 01-23-2021, 06:56 AM

Just wondering how you are making out with this issue. How about an update? -Paul

HackMan162 · 01-24-2021, 07:11 PM

The weather hasn't cooperated when I have had time, but I need to address this week, since I'd like to go out next weekend for a quick overnight. I'm thinking tomorrow afternoon will add quite a bit more water to the black tank, then Tuesday go for a drive and dump and see how it goes.

The more I think about it, and comments I have read, when I dumped previously, there probably just wasn't that much stuff in there.

HackMan162 · 01-28-2021, 03:43 PM

Well I had high hopes. Went out and leveled the rig the other day, and acquired enough dump hose to just dump at home. Went out and saw some brown matter in the clear fitting...this was encouraging. I thought, well maybe this was preventing the valve from closing all the way. I drained that into a bucket, then hooked up the hoses. Some brown matter came out, but not what I expected. Turned on the hose to the black tank rinse, and let er go for a few minutes....nothing. I then turned the hose off because I do not want to overfill the tank. Dumped the grey water tank, and clear water came out (I had ran the sinks for 5-10 minutes prior).
So, I had also gotten from WalMart the thing with the hose adaptor to shoot into the pipe. I ran that for about 5 minutes, but only clear water came out, just as if i had the valve closed.
So, I'm going to head out for a drive to the gas station right now, and will re-level and try dumping again (probably tomorrow morning). If that doesn't work I will try the pressure wash thing that PandS suggested. I really want to get this sorted, so I can head out the the moto track this weekend and camp.

hattitude · 01-28-2021, 09:27 PM

Quote:

Originally Posted by HackMan162

Well I had high hopes. Went out and leveled the rig the other day, and acquired enough dump hose to just dump at home. Went out and saw some brown matter in the clear fitting...this was encouraging. I thought, well maybe this was preventing the valve from closing all the way. I drained that into a bucket, then hooked up the hoses. Some brown matter came out, but not what I expected. Turned on the hose to the black tank rinse, and let er go for a few minutes....nothing. I then turned the hose off because I do not want to overfill the tank. Dumped the grey water tank, and clear water came out (I had ran the sinks for 5-10 minutes prior).

So, I had also gotten from WalMart the thing with the hose adaptor to shoot into the pipe. I ran that for about 5 minutes, but only clear water came out, just as if i had the valve closed.
So, I'm going to head out for a drive to the gas station right now, and will re-level and try dumping again (probably tomorrow morning).

If you had the black tank dump valve open and nothing came out when using the black tank rinse, that would suggest the dump valve was NOT open...Or did you mean just that no brown matter came out....???

If no fluid came out while using the black tank rinse, it is possible the dump valve control arm has separated from the valve, and is not opening the valve... Open the basement compartment on the opposite side from the the wet bay, and you'll be able to inspect the black tank dump valve (at least on my '14, which I believe has black tank plumbing set up like yours) and see if the valve control arm is still attached to the valve...

Here's a pic of where the black tank dump line exits the black tank. My valve is located in between the two red arrows....

I can't remember if the main toilet has a straight drop into the black tank, but it may be time to turn off the water, put a borescope down into the black tank via the main toilet, and see what's going on in there...

Good luck and let us know how this is resolved...

HackMan162 · 01-29-2021, 09:29 AM

I know my black tank valve would open and shut, but after your post I was not confident that it was opening 100%. I just went out and verified that it is opening.
Here's the latest update.
Yesterday evening, I went for a drive and filled the gas tank of the rig. Came back home and it was getting dark, so just parked. Went out a few minutes ago and leveled the rig. Opened the wet compartment and saw that there was some light brown matter in the clear angled adapter. The one on my rig has a small hose that comes out of that with a shut off valve. I drained this into a bucket. This would suggest there was an obstruction at the valve, since it had leached more brown (mostly water) into the drain line.
Not fully thinking this out, I opened the black tank valve and the bucket started filling. Finally, a very large clump of TP came through, which effectively clogged my small tube. I am encouraged right now, but cam in for another cup of coffee before tending to what is going to be a decent size mess. I am hopeful that the drain pipe is not more than 5 gallons after the black valve....
Stay tuned for an update.