Black water waste valve mystery

[Idaho Joe]

I just bought a pre-owned 2012 jayflight 19RD. I am a very experienced rv'er but can't figure this one out! While travelling down the road the black water waste valve opens by itself. Needless to say, this is not a pleasant discovery when you get to your next camp spot. Obviously the valve is almost new and yes it was completely closed after dumping. Since the underbelly is enclosed I could not easily inspect the valve. In frustration I finally cut the belly open and replaced it with a new one (even though the original looked fine). Guess what? The new valve does the same thing. This is a very simple mechanism and yes the four screws that hold it in are tight. I have fixed the problem by going to my local Ace hardware and purchasing a collar with a set screw which I placed over the shaft and behind the clamp that the shaft passes through. Now I just lift the rod and pull it through the clamp when I want to dump, but the original cause still baffles me. The only thing that I could come up with is the pull rod was tight against the lp line that runs along the frame and I wonder if it caused a harmonic vibration while travelling which caused it to open. Anybody have any other ideas?

[Boss Wagon]

Tough one there. You might be on to something re: the harmonic vibration. Maybe you should follow in another vehicle and watch for any trailer wheel abnormality issues. Just a thought.

[biester26]

If it's a 2012 why not take it back to the dealer and let them deal with it?

Just a thought.

Welcome to the forum!

[Idaho Joe]

This is a pre-owned trailer. Jayco does not transfer the warranty (unfortunately). The dealer (not a Jayco dealer) sold it "as is". The only other problem that I've had is the deadbolt lock on the entry door. It would not work with the key so I ordered a replacement from the lock manufacturer and replaced it.

[OnTheGo]

It sounds like you are experienced at finding and fixing mechanical problems, so there isn't much to add. Harmonics is a way of suggesting an undesired motion (vibration) is being created as you travel. Is there any play in the whole unit of pipes that might be transerring to the valve? Could you reposition the valve (probably not)?

In addition, you might want to call Valterra. They are usually very helpful, and that is their area of expertise.