Gone Outdoors

How to Replace a Black Water Tank in an RV

by Eric Cedric

The black water tank on a recreational vehicle holds the sewage and waste water from the rig's toilet. The black water tank is housed in a special compartment on the RV, usually on the rear left-hand side. A connection hose runs from the toilet to the tank, with an enclosed one-way valve inside the system preventing backwash into the toilet during transport. Should your RV's black water tank need to be replaced, you can do it yourself in about a half day's time.

Take the RV to a certified dump station found at campgrounds and some interstate rest areas. Pump out all waste and water from the existing black water tank. Drive the RV to your parking lot, set the emergency brake and disconnect all water and electric connections to the rig.

Open the black water tank panel, typically found in the rear left side of the RV's exterior. Put on gloves, mask and safety goggles to prevent contamination. Use pliers to remove the hose from the back of the existing black water tank. Pull the old tank out and place the new one into the holding area.

Go inside the RV to the toilet and check the hose connection on the back of the bowl. Push the hose out from the toilet so it extends into the holding area beside the new black water tank.

Slide a new hose clamp over the end of the hose coming out from the toilet and then connect the hose to the nozzle on the new black water tank. Tighten the hose clamp so it rests tightly over the hose and black water tank nozzle.

Apply a coat of silicone caulk around the end of the hose at the black water tank to provide additional waterproofing to the connection. Add a coating of the silicone caulk to the toilet's hose connection inside the RV as well.

Reconnect the water to the RV. Test the flushing and water flow to the black water tank by flushing the toilet once or twice.

Items you will need
  • Pliers
  • Screwdrivers
  • Hose clamps
  • Silicone caulk and caulk gun
  • Rubber gloves
  • Mask
  • Safety goggles

About the Author

A former Alaskan of 20 years, Eric Cedric now resides in California. He's published in "Outside" and "Backpacker" and has written a book on life in small-town Alaska, "North by Southeast." Cedric was a professional mountain guide and backcountry expedition leader for 18 years. He worked in Russia, Iceland, Greece, Turkey and Belize. Cedric attended Syracuse University and is a private pilot.

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