Step 5: If you have a portable waste tank.

 If you have a portable waste tank like we do currently, then there are some extra steps.

This step is more of an overview of how we do it rather than a "how to"

Our tank drains from the broad face rather than the thinner bottom, this in combination with where we have access to drain it forced us to create a way to elevate the tank. 

To elevate the tank we installed a pulley system which uses a metal ring at the bottom of the storage building, a pulley at the top and a cable puller and some rope to connect it all together.

These tanks are very heavy when full, I weight about 280 lbs. (127 kg) and with my entire weight on the other side of the pulley we could barely get the tank moving, so I would guess that the tank completely filled would weigh at least my weight. The point of mentioning this is ---SAFETY---, use only rings, pulleys, ropes and pullers rated for for the appropriate weight, everything in our system is rated for 400 lbs. (181 kg)

We have extended a pipe from the sanitary sewer to just outside the house. 

First with the tank still flat on the ground I remove the large cap from the tank and the sewer line from the house and attach the sewer hose to both,

I then lift the tank vertical and attach it to the rope (leaving the smaller breather cap on until after it is vertical and attached) then I remove the smaller cap so that the vacuum from the move starts a syphon and begins to drain the tank.

As the tank drains I lift it with the cable puller until it's as high as it will go, I drain until empty, and then lift and drain the excess in the hose.

After the tank is empty I attach the hose to the breather port and rinse the tank well before storing.

<p>Need help regarding draining black tank on a Dutchmen Aspen Trail travel trailer. It is not moveable. The sewer tank to dispose it into is about 40 feet away. It is also slightly elevated. Does the draining only work with the help of gravity, or is there an way to force the contents out, in spite of a slight elevation?</p><p>THANK YOU!</p>
I've heard if you are traveling and want to clean your tanks, dump some ice down the toilet and drive... Cleans up the tank nicely
Some RVs have a pump called a mascerating (spelling?) pump that is sort of like a high powered blender so that there are no solids in the tank at all. It might be a good idea to have that special pump. I believe that some rigs also use that pump to force the waste to dump.
I know this is an old thread, but a mascerator fits on the drain of the tanks. It only &quot;blends&quot; the stuff as you drain the tank. It doesn't do anything to the stuff going into the tank.
this seems like a no brainer but i had a hell of a time draining my tank. definately gonna make myself a wand like yours, as well as use the laundry detergent, thanks!
Please leave any improvement ideas, suggestions for deodorizers, or just general knowledge of the subject. I am not an expert and always appreciate learning a better way to achieve my goals.

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More by A little of this and that: How to drain an RV's black and gray tanks.
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