Our Keystone Cougar fifth wheel came with an internal black tank flushing system. It’s done a decent job for many years now but recently has become plugged. I’m not sure why but have suspicions the blockage is inside the black waste tank. All the external piping to it looks fine.
So, to flush out the black tank I needed to purchase a cleaning wand of some sort. The type that you pushed down into the tank from above through the toilet. Since our Cougar’s toilet drain has is slanted with a couple angled elbows a straight style wand wouldn’t do the job. I ended up buying the Camco RV Flexible Swivel Stik.
This RV waste tank flushing wand comes with a 55 1/2 inch reach and a section of piping that can flex to round corners. Inside the flexible tubing is a steel coil so it can be pushed through a clog. On the business end is a brass spray nozzle that can spin sending a water rinsing stream in all directions. The wand also includes a shutoff valve.
I tested it out on our black tank that I hadn’t flushed for several months. Right away the drain water became dark brown as the flusher went to work. After working with it for around a half hour the water was crystal clear, and even our tank level monitor was working showing empty again!
To finish up the job I added some Dawn dish soap to the tank and let her flush again until no more suds were seen. This as a good idea as it also cleaned off the wand so when I pulled it out it out it was clean as a whistle. I then let it sit in a bucket of water and bleach mixture for a few hours to decontaminate before storing.