Rear Black Water Tank always shows full

[seasure1]

After our last trip in March we went away last weekend. For some reason the rear black water tank always shows full even after it is completely empty.

Is there some sort of fix for this.


Thanks in advance

 

[SacRV]

After our last trip in March we went away last weekend. For some reason the rear black water tank always shows full even after it is completely empty.

Is there some sort of fix for this.


Thanks in advance

Does your rig have a black tank flush inlet? I've found when I don't do that and drain I'm still at 3/4 a tank. But when I flush it goes all the way down to 1/4.

 

[NXR]

The simple fix the next time you head to a site where you can dump:

Have about ten gallons or so of water in the tank. Pour about 8 ounces of a dishwashing soap through the nearest toilet. We use Blue Dawn. As you drive to the next site the water and soap will slosh around and sort of scrub the inside. Dump when you get to the site.

If you have a black tank flush, use it. Sometimes I'll add water to the tank and let it go to about 2/3rds and then pull the dump valve. BE CAREFUL! Many a person has gotten distracted and overfilled the black tank and bad stuff came up and out the toilets...

I do the same Blue Dawn treatment to the gray tank. I pick the sink closest to the tank, carefully pour the Dawn into the drain, put the stopper in and fill the sink. Then I pull the stopper and the water in the sink pushes the Dawn through the sink trap and into the tank.

Ray

 

[jmcclocklin]

I bought a water meter from Amazon and I put 12 gallons of water into my tank, then empty. I do it 3 times and my tank level always reads empty. I then put another 5 gallons in then put my happy camper in. Works great. Oh and I'm always watching my water meter !

 

[clanthon]

Had same issue with black tank and tried tank flush, driving sloshing water and dawn around but no go. The Lippert support guys told me how to check the 4 elect leads that go to the tank sensors and the “harness” that the leads are connected to was bad. Ordered a new one and it was easy to install. I also ordered a bag of the sensors in case I need to replace one.

 

[IDguy]

The only fix is to ignore it. This after 50 years with at least a dozen RVs.

After plugging the pipe several years and RVs ago stopped putting TP in RV toilet ( Mexican approach). No more plugging issues.

Black tank flush worthless. I rarely use it.

Never had an issue with black tank fill (except for one mistake while trying to use flush).

You can open the toilet valve and look down to see if you are filling it.

Since I mostly function off the fresh water tank it controls. Grey tank gets a lot more water than black. I hardly ever stay in places with hookups.

I suppose if you are an RV hookup user your concern may vary.

 

[IDguy]

Had same issue with black tank and tried tank flush, driving sloshing water and dawn around but no go. The Lippert support guys told me how to check the 4 elect leads that go to the tank sensors and the “harness” that the leads are connected to was bad. Ordered a new one and it was easy to install. I also ordered a bag of the sensors in case I need to replace one.

My bet is that it won’t help.

 

[Lars-of-D]

Had same issue with black tank and tried tank flush, driving sloshing water and dawn around but no go. The Lippert support guys told me how to check the 4 elect leads that go to the tank sensors and the “harness” that the leads are connected to was bad. Ordered a new one and it was easy to install. I also ordered a bag of the sensors in case I need to replace one.

Clanthon: what was the troubleshooting method the Lippert support guy taught you to troubleshoot the 4-elect leads?

 

[Jc4ut]

The dishwasher soap

Has worked great for me. When we move I drain the black tank then add a couple gallons of water and squeeze a bunch of dawn liquid down the toilet.
Upon arrival I drain black tank Then Flush black tank and so far after 2 years of full time use it still reads correctly.
Your mileage may vary as I also heard a bag of ice down the toilet just before leaving works great too but haven’t had to use that method.

Jimbo

Back to semi full time now about 9 months of travel

 

[bikendan]

Clanthon: what was the troubleshooting method the Lippert support guy taught you to troubleshoot the 4-elect leads?

Because you reawakened a 3 year old thread, I suggest that you PM that member since they haven't posted on the Forum, for the past two years. They may not be active anymore.