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Jillj712's avatar
Jillj712
Explorer
Jul 02, 2018

Black Tank Flush

I have a 2018 Coachman Catalina Legacy that has a black tank flush. I have hooked a hose up (not white water hose)to the inlet and turned the water on. I can't hear it running. I went into the bathroom and opened the toilet lid ( kept black tank release valve closed so I could see if the tank was filling up. I could see "stuff" rising so I hurried up and shut the water off and pulled the release valve to empty the black water tank and hardly anything came out. I have a clear elbow ( yuck). Do I just mess something up? Why didn't anything drain? First time camper owner and crappy information or no information for troubleshooting. At a permanent site so not in a hurry to take it somewhere. Just bought brand new in Sept. 2017.

Thanks,
Jill

10 Replies

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  • old_guy's avatar
    old_guy
    Explorer
    Jul 03, 2018
    sounds to me like you didn't start out with enough water in your tank and most of the stuff in your tank is solids. use a product called happy camper. it will digest the solids and toilet paper and if you start out with about 5 or 6 gallons of water and top it off with more water before dumping you will have a good flow of waste out your hose.
  • MDKMDK's avatar
    MDKMDK
    Explorer
    Jul 02, 2018
    Harvey51 wrote:
    The black tank flush entry hose connection may be confused with the city water connection.

    Our flush connection also serves as an overflow indicator - when the black tank is getting full, there is a bad smell, then a leak of brown water.


    Had thought about that one, but they're usually labeled, too. Good idea, though. A newbie could get them confused, I suppose.
  • Lynnmor's avatar
    Lynnmor
    Explorer
    Jul 02, 2018
    When you look down the toilet, are you sure that there is a lot of water down there? Open the valve by pulling the correct handle and see if anything comes out. If little comes out, close valve and dump five gallons of water down the toilet if it can take it. Now open the valve and see if five gallons comes out. If little comes out, you have a blockage or the valve is not opening. Repair valve or find the blockage. Sometimes the plastic disk from cutting the hold falls inside the tank when built. One possible solution is to push a hose up into the tank and turn on the water to flush. None of what I am saying is pretty, wear your bio-hazard suit or ask a septic pumping business if they can pump out the tank first.
  • myredracer's avatar
    myredracer
    Explorer II
    Jul 02, 2018
    I find sometimes it takes maybe 30 seconds +/- before I see water flowing through the clear elbow. At first it can be only a trickle.
    Depends a bit if the tank is tilted to one side or not. I usually do the initial dump, then turn on the in-tank rinser and let it run 1-15 mins. while breaking camp. Usually does a decent job of rinsing the bottom of the tank - at least what I can see from peering down the toilet.

    I would never ever close the dump valve and then run the rinser. All it takes is a distraction some day and forgetting that the rinser is running and you could have a very serious problem.

    FWIW, our rinser is visible when looking down the tank. Can you see yours?
  • Harvey51's avatar
    Harvey51
    Explorer
    Jul 02, 2018
    The black tank flush entry hose connection may be confused with the city water connection.

    Our flush connection also serves as an overflow indicator - when the black tank is getting full, there is a bad smell, then a leak of brown water.
  • MDKMDK's avatar
    MDKMDK
    Explorer
    Jul 02, 2018
    Jillj712 wrote:
    No moderator pump. No water comes out when I turn the water on for the black tank flush. On my gage panel inside the camper has a button for pump, but font know what that means.

    That's the water pump switch.

    Hate to ask but is the toilet looking like its still backing up when you look insude the toilet?
    Only other thing I can think of is make sure its the black tank dump valve handle you're pulling. Not the gray dump valve handle. They may look similar and may be close to each other. Should be labeled.
  • Jillj712's avatar
    Jillj712
    Explorer
    Jul 02, 2018
    No moderator pump. No water comes out when I turn the water on for the black tank flush. On my gage panel inside the camper has a button for pump, but font know what that means.
  • ScottG's avatar
    ScottG
    Nomad
    Jul 02, 2018
    The black tank just doesn't fill very fast with use. If you think about it, how much do we actually "put out" over a few days? Probably only a few gallons and the drain is a 3" pipe so it only takes a few seconds to dump unless you let it go a really long time.
  • time2roll's avatar
    time2roll
    Nomad
    Jul 02, 2018
    Wait for the tank to fill naturally, pull the lever to drain, turn on rinse, run water until clear, turn it all off, close it up. Rinse every time is a bit of a waste so maybe once a month. Otherwise just drain when full.

    That is my version. There will be others.
  • MDKMDK's avatar
    MDKMDK
    Explorer
    Jul 02, 2018
    Do you have a macerator pump to help empty your tanks? It might be labeled waste pump or some such. Probably near the waste valve handles. Or in the water tank fill bay or compartment.

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