Jump to content

Flushing black tank


Recommended Posts

We're new to trailering and picked up our OE2 in early November. We're in a campground in Florida for the winter before heading back to Michigan 

We have full hookups at our site and my question is his to properly flush the black tank

The video shows how to hook up but mentions nothing about what to do with the black tank drain valve  

Should we leave it closed while flushing or should it be open to drain into the sewer?

Prefer not to make a mess by mistake 

Appreciate advise from the more experienced  












  • Like 1
Link to comment
Share on other sites

travel trailer units for sale
Find Oliver Inventory Travel Trailers for Sale
View Inventory
  • Moderators

In almost all situations that I can think of - your black tank valve should be left in the closed position until you decide to drain it.  This would include flushing with the flush port.  The theory here is that the more water (liquids actually) in the tank provides inertia for any solids thus helping them move along down the pipe inside the Oliver and through the "stinky slinky".  The only possible exception to this is after I have filled the black tank a couple of times via the flush port, I will leave the tank valve open and let it flush for a minute of two.  I believe that this helps get any "final" little stuff off the walls and bottom of the tank.


  • Like 2

2023 Ford F150 Lariat 3.5EB FX4 Max Towing, Max Payload, 2016 Oliver Elite II - Hull #117 "Twist"

Near Asheville, NC

Link to comment
Share on other sites

  • Moderators

When our black tank is full, or needs dumping because we’re leaving for a location with no sewer, we dump, close the gate and fill to about 70-80%. Then we dump again and then repeat one more time.  I’m outside manning the outside dump activities and Carol is inside watching the level to tell me when we’re at the 70-80% level.  Then we drop in a detergent pod and a capful of Calgon water softener.  When we’re heading home we also add some Happy Camper to both the black and gray tanks.  We’ve been trouble free for the last 6 years.  Mike

  • Like 2

Texas Hill Country | 2016 Elite II #135 | 2020 Ram 2500 6.7L


Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...