Forum Discussion

d-mac1's avatar
d-mac1
Explorer
Feb 23, 2014

Fresh Water Siphons - Forest River XLR

When I bought the trailer the fresh water vent hose dropped down out of the underbelly and siphoned out the tank as you drove down the road. It would drop the level by at least 1/3, sometimes more. Haven't used the trailer alot yet, but took it to dealer and they moved the vent hose up to a new opening on the side right beside the fill port. Still siphons, but not as bad.

Talked to dealer recently and they said install a valve of some sort which can close after fill. Anybody do this? Issue for me is the vent hose isn't accessible without climbing in the cargo compartment which isn't too desirable when its loaded and in transit.

Also, the other opening to the vent hose obviously becomes submerged when tank is about 2/3 full. Dealer said can't change that. Seems to me that there should be a way to extract the hose which, it seems to me, is sticking down into the tank.

Thanks for any ideas.
Toy Haulers

4 Replies

  • d-mac1's avatar
    d-mac1
    Explorer
    Feb 24, 2014
    Does anyone know how a vent hose is connected to a fresh water tank? The dealer says its expoxied in. I think part of my problem is the vent hose is inserted too far into the tank as I can hear it when it goes under water. Once under water, the tank pressurizes.

    If there was a fitting I could loosen to retract some of it I think I'd be golden....presuming I could reach it.

    Good news on the vent valve! Found a short little metal valve that will thread right into the fitting on the side of the trailer. So I could leave it open just a smidge to let in air if desired...or close tight. The whole thing is 1 3/4" long, so only 1 1/4" sticking out once screwed in. Primo!!

    Thanks.
  • d-mac1's avatar
    d-mac1
    Explorer
    Feb 23, 2014
    Y-Guy wrote:
    A camping friend of ours has the same problem with their Motorhome. They left the line hanging down and installed a valve to open and close from there. The key is that if they start going up or down mountains they need to stop and open the line so it can adjust.


    Dang...I didn't think about the mountains issue. Great point! I live in Colorado and virtually everything is up and down.

    Seems there wouldn't be much expansion/contraction issue if full and could keep valve closed, but if partway full, then yes there could be an issue. My problem is mostly when my trailer is full so a valve should work...just gotta remember to open at fill and before use.

    If I'm hauling partway full, I could just leave it open. If I could put a vent cap on the side of the trailer that would seal it that would be ideal.

    EDIT - I went and looked at it...this might be easy! The vent fitting the dealer installed is a female hose thread....so same as what you connect to when you fill it. Trip to hardware store is in order. Sure there is a male plug of sorts.
  • ScottG's avatar
    ScottG
    Nomad
    Feb 23, 2014
    Our FR Wild Cat did the same thing - here is the fix: Inlet

    This water fill inlet moves the vent end up to a spot so high that the water can never spill or siphon out. It takes some minor surgery with a jig saw but it's well worth it.
    Worked great for us!
  • Y-Guy's avatar
    Y-Guy
    Moderator
    Feb 23, 2014
    A camping friend of ours has the same problem with their Motorhome. They left the line hanging down and installed a valve to open and close from there. The key is that if they start going up or down mountains they need to stop and open the line so it can adjust.

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