Clogged Black Water Flush

[KenandJoan]

I have purchased a used 2005 Coachmen Santara 3480DS and the black water tank flush valve is clogged. I am not sure where that check vaIve is located, maybe right where I attach the hose or on the side of the black water tank??

I have tried turning the hose on & off while using a vacuum breaker on the hose to give it a kind of "pulse" effect. If I leave the water pressure on, I get a trickle of water through the sewer hose, but that trickle does not increase as time passes.

I thought about putting some water in the black tank with a high concentration of Rid-X or maybe even Drano, and letting it "cook" overnight.

Since I am not sure where that valve is located, I do not know how much water would be needed in the tank.

Any suggestions would be appreciated.

Regards, Ken

[rlbarkleyii]

Do not put caustics such as draino, bleach, ect in the tank, it will corrode the valve and other metal hardware in the tank. It might even generate enough heat to damage the tank. Rid-x will do nothing to clean your tank. Rid-X is enzymes to work in septic tank, your holding tank is not a septic tank and does not utilize enzymes.

What you need is a solvent, water based, that will dissolve clud. TSP, Tri-sodium-phospate is my favorite for cleaning. You can get it in most hardware stores, it is a granular powder, a super strong detergent. It should not hurt your tank or valves. Fill the tank with water and add TSP and/or liquid laundry soap, if you can, drive around for a few minutes to shake it up. Let it set for 24 hours or so and dump. Rinse again and repeat if necessary. TSP makes water super wet and gets everywhere, should clear out your nozzles as well. Works for me.

[hermanmullins]

Would "CLR" work?

Herman

[nitehawk]

Maybe I am wrong, but isn't he talking about the "spinner" rinse mounted on the side of the tank to help clean the tank? If so I don't think any cleaner will help if the spinner is worn out. I replaced ours three years ago and this spring took the "new" one out and it seems to be kind of worn out already. The parts are all plastic and wear quite rapidly until they quit spinning. Also, his rinser might be clogged with paper. Easiest solution might be to just take it out and replace it, as only three screws hold it in.

If it is where the hose is connected, there might also be a anti-back drain valve that is blocking the water.

[campcop]

The check valve for the black tank flusher should be right at the connection to the water hose, if the only thing showing is the connection, look behind the panel.

[BillAdams]

Maybe I am wrong, but isn't he talking about the "spinner" rinse mounted on the side of the tank to help clean the tank? If so I don't think any cleaner will help if the spinner is worn out. I replaced ours three years ago and this spring took the "new" one out and it seems to be kind of worn out already. The parts are all plastic and wear quite rapidly until they quit spinning. Also, his rinser might be clogged with paper. Easiest solution might be to just take it out and replace it, as only three screws hold it in.

If it is where the hose is connected, there might also be a anti-back drain valve that is blocking the water.

Most tank flushers are not spinners. They are fixed plastic fixtures with a bunch of holes to allow the water to spray in multiple directions. This was the mistake I made. I took out a perfectly good fixed flusher and installed the Tornado spinner. After 2 failures I need to go back to the fixed one to prevent ongoing issues.

[KenandJoan]

Thanks to all of you for your suggestions.

ribarkleyii ---

I was wondering about damage that might result from using Drano. I have used TSP before, but did not think of it for this application, thanks for that idea.

nitehawk & campcop:

I was wondering if removing the screws at the hose attachment point would allow me to remove the check valve or"flusher". I may try that first. I attach and remove the backflow preventer with the rinse hose, so that is not the problem, but thanks for the suggestion.

Ken

[BillAdams]

If you have reasonable access to the tank flush assembly it's very easy to remove from the tank by unscrewing and then getting something between the tank and the flush flange. If you can do that, this is a great time to simply replace the unit and be done with it! If you replace it with something like this (it actually works!), it will cost you about $15.

http://www.campingworld.com/shopping/item/no-fuss-flush/3495

[KenandJoan]

Thanks Bill,

There are screws through the flange on my RV, as pictured on the one you suggested. Hopefully when I get the screws out, and the assembly removed, that will be the "flush unit", and it can just be replaced. I will let you know how it works out.

It will be a couple of days, as we are helping prepare for a granddaughters high school graduation this weekend.

Ken

[hermanmullins]

Ken, Congratulations to your Granddaughter. FYI, be sure your holding tank is empty before you remove the unit!! :huh:

[KenandJoan]

Thanks Herman, she is a great kid. Also thanks for the FYI, that could be a disaster!!

[KenandJoan]

FYI --- I removed the fitting from the panel, and it is attached to a hose that leads to the black water tank. I did not take the fitting apart, as we are camping for the next week, and did not want to create any problems. I will check into it further when we return. I have a rinse wand, but kind of a pain to run a hose thru a window every time I want to flush the tank.

Ken