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ramblingdan0103's avatar
ramblingdan0103
Explorer
Dec 10, 2017

Blackwater valve leak?

Hi everyone. Had our first night in our rv below freezing. Opened cabinets and ran the bathroom faucet a little and kept pipes from freezing. But, I found when the sink filled up and the toilet began leaking a little that the sink drains into the blackwater tank. Ugh. Went to dump and saw the valve was dripping a little. Dumped it and put some water back in. It doesn't seem to be leaking now. Question is, do you think this is going to leak again? If so, can I put some silicone or thread seal on the valve until I can replace it?

8 Replies

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  • mobeewan's avatar
    mobeewan
    Explorer
    Dec 11, 2017
    If it's fine now after greasing the gasket may have been a little dry.
  • ScottG's avatar
    ScottG
    Nomad
    Dec 10, 2017
    I've squirted them with cooking oil. Seems to work well and last a long time.
  • ernie1's avatar
    ernie1
    Explorer
    Dec 10, 2017
    Do not use petroleum jelly on the slide valve seals because it will eventually cause them to swell. Only use silicone lubricant on these seals since it is not a petroleum product.
  • ScottG's avatar
    ScottG
    Nomad
    Dec 10, 2017
    Personally, I would fix it. Plumbing leaks don't fix themselves - at least not for very long. I would not want to have to deal with the issue down the road at some CG.
    If you can let the tank dry out, replacing the valve is simple and straightforward.
  • ramblingdan0103's avatar
    ramblingdan0103
    Explorer
    Dec 10, 2017
    Nothing froze. It was only 29 degrees and I took some preventative measures. Just didn't reralize that the bathroom sink drained to blackwater tank instead of grey. It overflowed. I think it was due to too much pressure. I have flushed it out and put some petroleum jelly on it. Doesn't seem to be leaking anymore.
  • Lynnmor's avatar
    Lynnmor
    Explorer
    Dec 10, 2017
    If your dump valve is exposed to freezing temperatures, it may be cracked if water was in it.
  • ramblingdan0103's avatar
    ramblingdan0103
    Explorer
    Dec 10, 2017
    Thanks Kevin. I put some petroleum jelly on there just in case. I've done the job before, but, I am hoping it only leaked because the tank was too full and therefore more pressure. I'll keep my eye on it and replace if I see it leaking again.
  • ksg5000's avatar
    ksg5000
    Explorer
    Dec 10, 2017
    If it's not leaking I wouldn't worry about it. If it starts to leak then replace the valve. Most leaks are associated with deformed rubber gasket but the gasket cost almost as much as the entire valve so many just replace the valve. Replacement of the valve isn't expensive or particularly hard - lots of threads on that subject - use the forum search feature.

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