Holding tank liquid levels…

Nearly 3 years after I bought this Journey, still had the issue of the holding tanks indicator readings being inaccurate. Especially the black tank. The indicators showed the tank was full nearly all of the time. Sometimes just after emptying the tanks, it would show 1/3 full, but it would soon be showing ‘Full’ though the tank would still be close to empty. I’d developed a work around and there were indications that the tanks were getting full so usually I’d just go for 10 days then dump. Keep a sticky note above the indicator panel that lists the date of the last dump. That’s worked for nearly 3 years. But I’ve grown tired of that.

My black tank has a built in spray (used to flush the side of the tank where the probes are to keep them clean) and I’ve used it faithfully every time I dumped trying to clean the sensors. Never worked. So a couple weeks ago I decided it was time to do something about it. And the first thing I did was let the tanks get pretty full, poured 1 cup of Dawn Original liquid in each tank, and 1 cup of Calgon liquid water softener (only place I’ve found it on the road is at WalMart and only sometimes). Then I drove a couple hundred miles without dumping. When I got to my destination and dumped, the sensors for the black tank still read ‘Full’. At the tank, I removed the white wire and the display went to ‘Empty’ so that verified the wiring was OK. I was ready for this though as the week earlier I had ordered and received these Valterra Tank Probes.

Rather spendy for what they are, but when you don’t have access to a shop regularly, $31 isn’t too bad for a fix. Since I’d verified (again, for the 3rd or 4th time since I bought the rig), that the probes were bad and cleaning wasn’t going to fix the problem it was time to replace them. And here’s a shot of the tank. I’ve snipped a couple zip ties to access the wires, and removed the white wire which on most Winnebago products is the hot wire…doing so caused the indicator LEDs at the control panel inside the RV to read ‘Empty’. This verified that the wiring and indicators are working.

And here (next photo) I’ve marked the tank so I know what wire colors go where, cut the original wires off and drilled new 3/8″ holes for the new sensors and installed them. Two of the holes were drilled where they’d indicate the same as the old indicators but they now are where I could get the drill inside the compartment. Access to two of the sensors were blocked by the RV’s exterior wall. The level probes were originally installed in the tank before it was installed. I did try to pry out a couple of the old indicators but they were really stuck in there. It was so easy & quick to just drill new holes that I did that for all four of the sensors. The new sensors have a hood over the metal wire level sensor so any TP or solids that might come close and hang onto the probe probably won’t cause a false reading as the hood will protect it. There’s a small notch on the end of the bolt outside the tank that indicates when the hood is in the right position.

After the Valterra sensors were installed, I just crimped new connectors onto the wires attached them to the new sensors and bolted them down. Boom, done.

The drawing provided by Winnie has wrong wire colors so writing on the side of the tank was better than using the documents. Some readers may decide to just try to remove the old sensors but in my case, being the RV is 16 years old, I just felt it was safer to drill new holes than try to get the old rubbers, metal indicators, and screws out. I tried to get a couple out but they tend to spin so the screw couldn’t be removed in my case, and if I cut the rubber and screw head off, and pushed the remainder inside the tank, I ran the risk of those parts blocking the valve ‘open’ when I tried to drain the tank, somewhere down the road. Likely in the worst possible situation too. So just drilling new holes for the new sensors was, for me, the best and safest course.

You can see the marks I made with a straight edge and level to line up the new ‘Full’ sensor with the old one. The tank is tilted from the factory so I had to adjust the position of the sensor so it would be in relatively the same liquid level. The others were basically eyeballed.

After installation of the new sensors, I filled the tank with water using the built in sprayer and watched as each LED lit in turn. And it all worked as expected. Drained the tank and I’m ready to use it normally.

And here’s the tank indicators working correctly!!

So now my black tank indicators will be accurate for the first time since I bought the rig. Yea!

Update: Less than a month later…

Didn’t work. Still as flakey as always so I have to keep my post it note with the dump dates current.