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Atlee's avatar
Atlee
Explorer II
Feb 22, 2018

By passed Black Tank Flush back flow preventer

The back flow preventer failed after 5 months of use. Was going to replace it yesterday, but @ $50, I decided no. Looked for a simple plastic elbow, but couldn't find one, so made a brass one. Also...
Atlee's avatar
Atlee
Explorer II
Feb 28, 2018
At this point, I have purchased a back flow preventer to put on the outside of the black tank flush. It should do all that's needed to fix the problem.

mikestock wrote:
Had a similar problem in a previously owned Montana fifth wheel. Like you, I found the price for this plastic junk to be outrageous. The thing was manufactured to fail. I bought a generic check valve and other parts to create my own, better version for a fraction of the cost. Functionally the same.

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