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Mark_Heron's avatar
Mark_Heron
Explorer
Aug 02, 2015

Toilet/Black tank issue

Just got back from second trip, departed Friday afternoon, black tank empty by Saturday evening black tank is full and toilet backed up. Black tank is 37 gallons, had to use portable dump tanks to empty which sucked BTW. 9PM last night black tank is empty by 8AM this morning black tank 2/3 full. Toilet is gravity discharge Sealand toilet model 110. I did notice toilet does not seal after flushing and bowl will be dry shortly after using. My thought is toilet is running slowly and filling black tank, that is the only explanation I can come up with that tank would be 2/3 filled in 12 hours. I do not hear water running into tank but this {in my mind} could be the only reason. Anyone had this happen or possibly have a different thought on my situation? Any help would be great, thanks in advance. Trailer is 08 Keystone Cougar 300

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  • rv2go's avatar
    rv2go
    Explorer II
    Aug 02, 2015
    Turn on the water pump. If the toilet is leaking, you should hear the pump cycling on and off. Also, after flushing, you should pull up on the foot lever in order to help seat the seal.
  • Mark_Heron's avatar
    Mark_Heron
    Explorer
    Aug 02, 2015
    Last night gauge was reading full and toilet was about an inch from over flowing. 3 trips to dump station with portable dump cart so I'm fairly certain it was full. I know it was empty last night, visually and gauge was reading empty as well. This morning 2/3 full, toilet was used 4 times in 12 hours. So water is going into tank from someplace
  • therink's avatar
    therink
    Explorer
    Aug 02, 2015
    Are you relying on the electronic level gauge to tell you how full the tank is? If so, ignore the gauge. They are not accurate, specifically the black tank. As soon as TP touches one of the gauge sensors, it closes the circuit and tells you it's full.
    I have a 37 gal black tank and can go about one week with 4 people before I need to dump, and we use it a lot.
    If your toilet pipe is clogged, you likely have the well known poo pyramid forming at the bottom. This is generally caused by not having enough liquid in the tank to start.
    After dumping I always add about 3 gals of clean water before using the toilet. Today's holding tanks are only abt 6 inches high and very wide. Water is need to disperse the solids so pile doesn't Form on the bottom

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