Forum Discussion

mejones53's avatar
mejones53
Explorer
Aug 14, 2013

Leaky Valves

We're just back from a one month (4000+ mile) road trip with two of our grandkids. Halfway through the trip I noticed that the blackwater tank valve leaked. This happened after boondocking for the night and then moving on to our next stop. When I went to dump there was an estimated quart of "liquid" that came out when i took the cap off.

Not wanting to have a repeat, I went and had an RV dealer (Camping World franchisee) replace the black tank valve. Things appeared to be all well and good till I had reason to travel without the opportunity to dump. Our travel was over roads that were far from smooth, we got tossed around quite a bit . Needless to say the next time i went to dump there was about a quart of "liquid" spilling out when i took the cap off.

Do I need to have the valve replaced again or will a couple of hundred miles of bumpy roads cause valves to leak?

9 Replies

  • opnspaces's avatar
    opnspaces
    Navigator III
    Aug 19, 2013
    Yes it just twists on to the end of the pipe where your sewer hose connects. Here's a link. Link
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 19, 2013
    rv2go wrote:
    I don't think a new valve should leak if properly installed. There is a small possibility the valve is defective.
    I carry one of these in case I have a leaking valve while on the road and it will be a few days until I can get it replaced.


    Does that just turn onto the main opening like a sewer hose does? Pic is kinda small to see for sure.

    Do you have a link that describes that and where to purchase one? I've never seen such an add on, and it sure WOULD be a good think to have on board just in case. Thank you.
  • thewhitehat's avatar
    thewhitehat
    Explorer
    Aug 15, 2013
    rv2go wrote:
    I don't think a new valve should leak if properly installed. There is a small possibility the valve is defective.
    I carry one of these in case I have a leaking valve while on the road and it will be a few days until I can get it replaced.


    This is your best bet. Valves will leak. New valves will eventually leak. Slapping a couple of these on is the easiest thing to do.
  • rockhillmanor's avatar
    rockhillmanor
    Explorer II
    Aug 15, 2013
    Been there done that. Replaced it twice, and still leaked.

    Turns out it was leaking from a 'hairline' crack around the tabs on the sewer line where you screw the valve in.

    Checked the gray tank valve and there were hairline cracks around the screw tabs there also.

    RV repair says they see this a lot because if you look at your sewer line assembly it is suspended and it moves up and down and the movement of the RV puts stress on the screw points.

    The hairline cracks were not easy to see but that is where it was leaking from. When we removed the valve the second time after seeing the cracks, 2 of the screw tabs actually broke clean off.
  • mejones53's avatar
    mejones53
    Explorer
    Aug 15, 2013
    Thanks for the comments and feedback. I'll just changed it out. Maybe i'll find something is keeping it from shutting properly.
  • rv2go's avatar
    rv2go
    Explorer II
    Aug 15, 2013
    A good way to tell which valve is leaking is to add a packet of Red Rit Fabric Dye to the gray water holding tank. First firmly seat the valve, add the dye, then run several gallons of water into the tank. Let sit for a while. You will see the red water if it's leaking.
    If no Red, then it's the Black tank valve leaking.
  • JJBIRISH's avatar
    JJBIRISH
    Explorer
    Aug 15, 2013
    Are you certain you replaced the right valve, black and gray usually exit the same terminating point and one can smell as bad as the other…
  • therink's avatar
    therink
    Explorer
    Aug 15, 2013
    Was anyone using baby wipes?
    A few made it into my black tank on my new fiver and became lodged in the valve seat. This made the valve not completely close. I ended up taking the valve off and find it. It was lodged real good in the valve seat groove and flushing would not remove it. I removed it with a screw driver, put everything back together and all good now.
  • rv2go's avatar
    rv2go
    Explorer II
    Aug 14, 2013
    I don't think a new valve should leak if properly installed. There is a small possibility the valve is defective.
    I carry one of these in case I have a leaking valve while on the road and it will be a few days until I can get it replaced.

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