Black tank dump valve

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marcortez

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Joined
Jul 31, 2015
Posts
141
Location
Desert SouthWest
2017 Jayco SLX 245RLSW

Ongoing problem since new. It's time to do something.

Can't take it back to the dealer.......I am deep in Baja Mexico and a 1000 miles away.

The black tank drain volume is just a trickle....even after 30 days of use.
No paper has EVER been deposited and less than 4 "emergency" consistancy loads since brand new.

Nightly liquid deposits during this last 30 day period, with every other time flush.

Gauge says "full" with all 4 lights lit up. Started out from 3 lights.

On draining, the flow is a trickle.....while the gray was full on flow and empties well.
First go round was trailer level.......second attempt the drain side was down a bit. Still weak but a tad better.

Push/pull handle for the valve seems to operate ok.

Looking for help for a solution to the trickle drain.

Layman guess would be the valve is not opening fully, or construction debris is blocking the flow
Solids build up is a non factor.....not enough deposits to make that a concern and always with copious amounts of water first and after......with chemicals.
No paper ever.....

What say you?
 

Rene T

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May 20, 2011
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Farmington NH
Do not rely on the level indicators. They typically stop working after a while.

With the drain valve shut, put in several gallons of water. Remove the sewer hose. Let it sit for a while then go out and see if fluid is dripping out of the sewer outlet.  If it is, what may be happening is all the fluid is slowly draining out of the tank overnight and leaving behind just solids and thereby building a poo pyramid plugging up the tank exit. If it is leaking, in the meantime, go out and purchase a spin on 3" sewer drain valve. Put this on your sewer outlet. It will stop any fluids from leaking down the hose. Many people use them and leave it on all the time. I do. It's a backup valve if yours is leaking.
 

marcortez

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Jul 31, 2015
Posts
141
Location
Desert SouthWest
Rene......

The sewer hose is not connected.
Holding tank only.
The cap is always in place.
There is a small amount of liquid that comes out on cap removal.....a couple of teaspoons worth.

On edit.......another Q....

Normally.......where is the exit hole for the black drain out?......right below the "deposit" plop area or off to one side?

 

lynnmor

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May 14, 2013
Posts
1,585
marcortez said:
Rene......

The sewer hose is not connected.
Holding tank only.
The cap is always in place.
There is a small amount of liquid that comes out on cap removal.....a couple of teaspoons worth.

On edit.......another Q....

Normally.......where is the exit hole for the black drain out?......right below the "deposit" plop area or off to one side?

If you need help, may I suggest you write the questions in English?  Nothing you said in the above quote makes a bit of sense.
 

Rene T

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May 20, 2011
Posts
17,344
Location
Farmington NH
marcortez said:
Rene......

The sewer hose is not connected.
Holding tank only.
The cap is always in place.
There is a small amount of liquid that comes out on cap removal.....a couple of teaspoons worth.

On edit.......another Q....

Normally.......where is the exit hole for the black drain out?......right below the "deposit" plop area or off to one side?

On mine, it drops about 12" right in front of the exit hole. I believe most will be that way. They drill the hole for the inlet pipe usually in the center of the tank.

Can you look down the hole in the toilet with a flashlight and see the bottom of the tank?
 

Gary RV_Wizard

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Feb 2, 2005
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73,533
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At our Silver Springs FL home
There is no "normal" place for the drain - it's wherever it is convenient to mate to the tank and reach the outside valve area. The tanks get mounted wherever there is room and pipes get run where they can.

The two most obvious potential problems are a failed valve or construction debris. Neither are common, but still the most likely to explain your symptoms. Both require  some disassembly to investigate and fix.


Were your drain attempts ultimately successful in getting the gauge down to Empty? How long did it take?  As Rene says, the lack of a decided whoosh of water is bad even if it empties, because semi-dissolved solids and paper will build up if the water flow doesn't carry it out.
 

marcortez

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Joined
Jul 31, 2015
Posts
141
Location
Desert SouthWest
Gary RV_Wizard said:
Were your drain attempts ultimately successful in getting the gauge down to Empty? How long did it take?  As Rene says, the lack of a decided whoosh of water is bad even if it empties, because semi-dissolved solids and paper will build up if the water flow doesn't carry it out.

Never successful according the gauge idiot lights.
Before drain, it shows full.......after drain it shows 2/3rds full.

I use the toilet as recommended.......add water to the tank........add water to the bowl.......make the deposit and flush copiously.
Never has the tank seen one section of paper....ever. And in the trailers entire life span (1.5 yrs), not more than 5 solid deposits and those were the 3 AM emergency style deposits. I make good use of campground facilities

It's worth noting that I rarely do a hookup.....99% of my camping is dry and full on boondock and the waste water is always in the tank until I find a suitable dump station. Which has been up to 30 days.

Deodorant chemicals added but not sure if they are the "digesting" type or not.

Gray has great whoosh......full flow. The clear elbow end is full.
Not so with the black.....elbow about 1/4 full, slowing to a trickle in short order.

Either I am not using the toilet with sufficient frequency to "load it up" for a full flow or there is some blockage.

Thank you
 

grashley

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May 7, 2015
Posts
6,566
Location
Western Kentucky
I recently purchased an endoscope with a 5 Meter lead for around $20.  It can be connected to many phones and laptops with a USB.  Run it up the drain and take a look.  It will not fix anything, but it can show you what the problem is!  Yes, it is waterproof.

https://smile.amazon.com/Depstech-Semi-rigid-Inspection-Waterproof-Adjustable/dp/B0749BQG1B/ref=pd_ybh_a_40?_encoding=UTF8&psc=1&refRID=ZTHSC5WXQWH6ZQEC4F2C
 

BikerFlex&HappyJen

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Joined
Mar 25, 2017
Posts
178
We had an issue on our maiden voyage with a brand new tt. We had a backed up toilet. We tried being too frugal with water. Never again. Now I try to always sprinkle some powdered RidEx after each dump station so it helps break up anything in the black tank. I keep a small box of it in a sealed plastic bag in the bottom of the bathroom vanity.  I also use a tank sanitizer or the smell is not good. Even the first few times using the tt the black tank sensor didn?t show correct after a dump. After a tank dump, I check the sensors, and most of the time the black tank one doesn?t read correctly. I then dump three 1 1/2 gallon buckets of water into the toilet to the black tank and that usually resets the sensor to empty almost every time.

During the clogged toilet, I added ridex and some dawn dish soap to the toilet and it sat overnight. The next day we used a drain snake and gently made a path from the toilet to the black tank and it finally broke free. We had to carefully move it down without rotating so the snake wouldn?t get stuck.

As Rene suggested you may have a poop pyramid that had made its way to your black tank sewer exit and blocked it. Try adding some ridex and dawn dish soap and then add some extremely hot water to your black tank via the toilet. It may take awhile for it to dissolve.  Hopefully it will break up the blockage if that is what is causing your plug.

Oh, if possible make sure your tanks, especially black tank, are 2/3 full before dumping. The pressure helps push everything out. Even if you have to top your black tank off with water before you head to the dump station.

Please update your thread once you resolve your issue so others may learn from your experiences. Hope all goes well for you and you get it resolved!
 

lynnmor

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Joined
May 14, 2013
Posts
1,585
BikerFlex&HappyJen said:
We had an issue on our maiden voyage with a brand new tt. We had a backed up toilet. We tried being too frugal with water. Never again. Now I try to always sprinkle some powdered RidEx after each dump station so it helps break up anything in the black tank. I keep a small box of it in a sealed plastic bag in the bottom of the bathroom vanity.  I also use a tank sanitizer or the smell is not good. Even the first few times using the tt the black tank sensor didn?t show correct after a dump. After a tank dump, I check the sensors, and most of the time the black tank one doesn?t read correctly. I then dump three 1 1/2 gallon buckets of water into the toilet to the black tank and that usually resets the sensor to empty almost every time.

During the clogged toilet, I added ridex and some dawn dish soap to the toilet and it sat overnight. The next day we used a drain snake and gently made a path from the toilet to the black tank and it finally broke free. We had to carefully move it down without rotating so the snake wouldn?t get stuck.

As Rene suggested you may have a poop pyramid that had made its way to your black tank sewer exit and blocked it. Try adding some ridex and dawn dish soap and then add some extremely hot water to your black tank via the toilet. It may take awhile for it to dissolve.  Hopefully it will break up the blockage if that is what is causing your plug.

Oh, if possible make sure your tanks, especially black tank, are 2/3 full before dumping. The pressure helps push everything out. Even if you have to top your black tank off with water before you head to the dump station.

Please update your thread once you resolve your issue so others may learn from your experiences. Hope all goes well for you and you get it resolved!

The only RID-X product that will do anything for an RV tank is this: http://www.rid-x.com/products/rv/rid-xreg-rv-toilet-treatment-liquid/
 

meternerd

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Joined
Mar 30, 2012
Posts
158
Since you probably have no access to a RV parts store, you might try this.....(don't shoot me, I'm a jury rig expert).  If you can connect a water hose and get some fresh water flow, use a wet towel wrapped around the hose, wedge it tight in the sewer outlet, open the black water valve and try to back-flush it.  I know they sell back-flush fittings that basically to the same thing but much more elegantly.  If all you have is your fresh water pump for pressure, you might look for a friendly person to let you hook up to his water faucet for more pressure.
 
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