Tank Probes

[Wannabes-SUN]

Any of you clean your holding tank probes lately?

We routinely get weird readings from our tank monitor panel, e.g., the panel claims that the gray tank is full when in actuality it has not even been used yet. So, I decided it might be good to remove and clean our gray and black tank probes so as to improve the accuracy of their readings.

With this goal in mind, I removed the first nut on the uppermost black tank probe, removed the sensor wire, removed the second nut, took off the washer next to the rubber grommet, and then finally used a plastic scraper to loosen the grommet itself from the exterior of the wall of the black tank. I expected after these preparatory steps easily to be able to remove the probe.

NOT!! The probe did not want to come loose. So I pulled on it, by hand. Nothing. I then twisted it, also by hand, first one way and then the other. Nada. I pulled some more, and the probe did not budge. So I put one of the nuts back on the threaded (exposed) end of the probe, and used the other as a jamb nut. Grabbed the two nuts with pliers and pulled, expecting that the probe would slide out. NOT, again!! I continued to pull on the probe, to the point that the side wall of the black tank actually bulged noticeably outward. Still no good. At this point I stopped, thinking that clean tank probes are not worth a ruptured tank wall.

Put everything back together and tried an adjacent probe, thinking, well, maybe it was just this one probe that had an issue.

Wish I could say that this was the case. This second probe behaved in exactly the same fashion as did the first one.

So: What am I doing wrong here? There must be a trick to taking out these tank probes that I'm missing: can someone please tell me what it might be? Our unit is a 2002 model 2363.

Matthew

 

[jim44646]

Once pulled they seldom can be reused. They are not that expensive to replace. about $2.50 each. once I found them for $.20 each. Easiest way to remove is to remove nuts, put a box end wrench a little larger than sensor rubber up against tank slip a fender washer (big washer, small hole) on threads against wrench thread on nut and tighten. As you tighten the sensor will pull from tank. pop in a new one tighten nut apply wire add second nut. Not pushing horst probes just showing easy removal of probes.

 

[Relie]

Tank probes

Thanks for the post and video. This looks a lot easier than I expected. I plan to do this in the spring. My black tank reads full all the time, so I assume that the probe is bad. The grey tank is ok. The battery also reads all 4 dots on the monitor, and I have no idea what's going on with that one ( will deal with that in the spring). The battery discharged to the point where I needed to use jumper cables to work the electric lift. Maybe a new battery is in the future things to buy. Anyway, thanks for the sensor post.

Dave

 

[jim44646]

Those tank monitors are just guide lines like idiot lights on cars. Gives you an area to investigate.

 

[jim44646]

Really there are 4 probes. Bottom one is ground. When tank 1/3 full it contacts 2 probes 1/2 full liquid is contacting 3 probes sect.

 

[Relie]

Tank probes

Jim, are you saying there are 4 probes on the T2553? I have a 1999. Just checking, hate to buy 4 probes if I only have 1 or2. Going to do this as my first spring project .

Dave

 

[jim44646]

Jim, are you saying there are 4 probes on the T2553? I have a 1999. Just checking, hate to buy 4 probes if I only have 1 or2. Going to do this as my first spring project .

Dave

Yep. 4 probes per tank. Here a photo of a fresh water tank. All tanks setup the same. Bottom probe (white, ground) Next #2 (yellow 1/3 full) #3 (Green, 2/3 full) Top #4 (red, full). Second photo is the harness. The Red tab is a resistor. As you can also see any level between Full probe and 2/3 is going to read 2/3 full. As soon as liquid level falls below the 1/3 probe you will show empty but you may still have 10 gallons left. It's the liquid touching probes that complete circuit.
On your black tank you may have slime build up on the sides of tank completing circuit. You may want to try Happy Camper Extreme tank treatment to clean your tanks well and get rid of any build up.
The first time I used it I couldn't believe the black crud and crust that came out. I use a clear tube between my outlet and hose so I can see clean water come out when I'm flushing. I also installed a tank flusher kit.

 

[Relie]

Tank

Jim, thank you very much for taking the time to post the photos. Very helpful, and informative. I think the first thing that I'll do in the spring will be to flush out the tank. Then move on to replacing the probes. Again, thank you and happy camping.

Dave

 

[Wannabes-SUN]

Jim,

Thanks for the YouTube video; will give that a try. Less hassle to replace with new than clean the old but had read on other sites that some people clean theirs. We know that the tank probes are not exact but our gray tank never seems to read what it should. Wife ordered Happy Camper this spring and we've used it in the black tank throughout the summer; also got a tank flush kit. Between the two our black tank probes are giving a more accurate reading. (Sorry this reply is a bit behind the times; we've been having 'net issues.)

 

[jim44646]

Just make sure you tilt TT so that probes are on the high side of the tank. You may get a surprise when you pull the bottom probe.