Black & grey water tank draining.

BigBlue

BigBlue
When I drain the grey water tanks, they never fill up the sewer hose like my old Montana trailer did. When I drain the black water tank, it fills the sewer hose at the beginning of the draining process and then quickly tapers off. The reason I can tell how the water is draining is because I use a clear 5 inch connector so I can see what's going on. I use the black water flush and also have put Calgon water softener in the tanks to clean them but nothing has changed.
Are your tanks working the same?
 

fireflipper

EX-Travel Bug
Fireflipper

HI BigBlue
I believe this is because the grey tanks drain into a 1 1/2" pipe and the black uses a 3" pipe. I also use a clear peice at the outlet and the smaller pipe will not let enough water out to fill the sewer line. This in turn also makes it take a lot longer to drain the grey tanks.
 
I have heard of build in holding tanks, if your parked and leave your drains open the water leaves the solids and you get a build up in the tanks. You might have to go down throught the toilet and brake it loose. Check it out?
 

phranc

Well-known member
The black tank empty's fast so it might taper off towards the end. The factory must have gotten the venting right because the tank empty's really forceful and fairly quickly. As Fireflipper said the Gray tanks(2) pipe is smaller than the black and will drain slower. But still will flow enough to rinse the hose out..
Sonnybeech. It would be Ok to let the gray tanks drain open when at a CG and then close them a day or so before leaving to let the gray build up to have enough liquid to flow properly and also to rinse the hose
BUT.. you should not leave the black tank valve open as the liguid will drain out and MAY leave the solids behind which will cause a problem later on..The Gray tanks should have almost no solids in them.
 

BigBlue

BigBlue
I know about leaving the black tank closed. I usuallly keep the grey tank closed until it's necessary to drain. I've used calgon in the black tank to get it as clean as possible. I just don't see the tank draining as my old fiver did and I'm worried that it might plug up sometime because it doesn't flush strongly.
 

BluegrassMan

Well-known member
Gray & Black tanks

Hi Guy's:

I'm sure everyone has their own way they hold then drain. I never crack open the gray. I let EVERYTHING build up, when I dump I do the black first. When it starts to slow down I open BOTH gray water valves. The pressure fills the hose and goes BACK in the Black tank. Thus it helps to flush the remaining black out before you rinse.

I don't know if anyone else does this, it seems to work OK, I always have good flow through the sewer hose.:D
 

azrv

Full-timer
Have had trouble with black-water line/tank clogs. Now use chemical and faqbric softener to lubricate lines, has helped somewhat. Also use 'power flush' after each draining of black-water tank. Idea of opening both grey-water tank lines is worth trying, thanks for the idea.
 
K

Ken Washington

Guest
I think it is important to flush everytime you dump. Make sure to use the right kind of tolet paper and chemicals. I close the valve for just a fue mimutes while the flush is running to add water to the tank (after it is empty) and open again to flush some more. I do this several times. I have a clear extention so that I can see when I start to get clear water. Caution; Nevar walk away to do something else while doing this! If you left the water running to long with the valve closed, it will back up into your trailer!
 

jbeletti

Well-known member
I now do the same as azrv and Ken W - power-flush the black tank each time.

I didn't do this the first few times out. Doing so now, with the clear extension really gives me an appreciation for the power-flush heads. I drain, close, power-flush, drain and repeat several times until the water is running as clear as I have time to spend doing this.

Makes me wish I also had power-flush nozzles in my two gray tanks as I am sure we get sludge build-up in them. We are not super dilligent about make sure that no food particles go in the tanks.

Jim
 
K

Ken Washington

Guest
Hi Jim,
If you keep a little water in the tanks like I do, drain them as soon as you hook up after being on the road and that will cut down on sludge build-up. I always keep about five gallons in all tanks except during winter.
Ken
 

jpmorgan37

Well-known member
I had the opportunity to go to a seminar on tank maintenance a few years ago and what they told us has worked quite well for me. The recommendation was to fill each tank approximately 1/3 full and add 1/4 cup of "original Dawn" to each tank before driving at least 100 miles. The Dawn will wash the grease and solids breaking them loose and then dump when you reach a destination. The other thing was tissue in the black tank. Cottonelle because of the cotton fibers and any brand with Cold Cream in it were not to be used. Do a test-put a piece in a bowl of water and let it set for overnight. If it disolves, it's good to use. And the black water tank flushing after each draining as previously mentioned. This has kept my tank level indicators working perfectly over the years.
 

happyrover

Active Member
Have tried just about every method for storing and draining tanks, both grey and black over the years, and would recommend the following. Keep tanks closed until almost full, dump black, then flush with grey. Keeping both tanks full keeps most of the waste in suspension and easier to get out. Then flush both tanks each and every time to keep them clean. Installed a macerator pump 2 years ago and it sure works great for dry camping. Am changing over to Landmark from motor home in the spring so will have to learn about dual grey tanks. Looking forward to the new adventure.
 

Trap

Well-known member
jpmorgan37 said:
I had the opportunity to go to a seminar on tank maintenance a few years ago and what they told us has worked quite well for me. The recommendation was to fill each tank approximately 1/3 full and add 1/4 cup of "original Dawn" to each tank before driving at least 100 miles. The Dawn will wash the grease and solids breaking them loose and then dump when you reach a destination. The other thing was tissue in the black tank. Cottonelle because of the cotton fibers and any brand with Cold Cream in it were not to be used. Do a test-put a piece in a bowl of water and let it set for overnight. If it disolves, it's good to use. And the black water tank flushing after each draining as previously mentioned. This has kept my tank level indicators working perfectly over the years.

If you add calgon watner softner along with the dawn before driving it works even better.

Trap
 
I have a problem draining my tanks now that I never used to have. The last couple parks that i was at, the same thing happened, when I drained my tanks( black or grey)they would drain fast just for a few seconds, then it would stop just like it was air locked. If I would burp it by giving it some air on the sewer end , then it would drain fast again for a few more seconds, then I would have to burp it again. Any help on this matter would be appreciated. I forgot to say that this is a Big Horn.
 
Top