Black Tank Flush 3900FB

vibetech1

Advanced Member
Joined
Aug 6, 2008
Posts
66
We recently purchased a new 3900FB with the extra 1/2 bath. The unit came with black tank flush systems for both black tanks. My concern is the 1/2 bath flush doesn't seem to be working properly. With the flush system running I can open the flush valve in the trailer and see that there is a very light spray of water barley reaching the center of the tank. Also while its running you cant hear it spinning. When I run the flush system for the master bath it actually sounds like something is spinning in the tank but because of the location of the toilet i cant visually verify that is.

Does anyone know what type of black tank flush systems Keystone uses in the newer Montana's? The only spinning type that I can find is the aftermarket Tornado. I wonder if there's a higher quality spinning flush system specifically designed for new manufacture installs. The flush system we had on our Cardinal travel trailer would spin and clean our black tank to where you could see the bottom of the tank and know it was clean.

Thank you in advance for everyone's help in this matter.
 
I thought it was the Tornado brand spray flush that was installed in our '06 Montana from the factory. It was been working great for us. We only have the one black tank for the main toilet.

Make sure when using any toilet that there is plenty of water to process the waste. There's more to it than just watching the effluent leave the tank. You need to let a lot more water down there too. Or you might be clogging your tank with all the waste. I hope you aren't having this problem.
 
Art, thank you for your response. We took our 5th wheel back to CW to have it checked out. Initially they called and said the 1/2 bath flush was working fine. I asked them to please run the flush system in the master bath and listen to the difference. After doing so they called back and said they were ordering a new flush kit. The confusing part for me is he said based on the parts diagram the flush system appears to be stationary and that both the master and the 1/2 bath show the same part number. I'm 99% sure based on sound the master flush is spinning. Either way I asked the service tech that once the part arrives and that if its a stationary flush then please let me know and I will gladly pay to have them install the Tornado in both tanks.

We are generally using full hook up's so my policy (regardless if it's #1 or #2) is to always give a minimum of a 10 second flush. We've been RVing for close to 10 years and have never had plugging issues. Our first RV didn't have the flush so when we purchased the Cardinal with the spinning flush system you could imagine my amazement of how well it cleaned. I told myself I would never be without it again.

Thanks again Art.
 
I would assume you should have the spinning one on both tanks and it should do a good job. Sounds like you got a bad one out of the box.
 
Is the water flow activating both at the same time or are they individually run. If both are running at the same time, it may be the least flow of resistance theory here. Ask the dealer if there is a way to run them separately. Just a thought. Good luck. :)
 

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