Black and grey tank issues

[cmikal]

I have a new 377RLBH, still under warranty, but due to a non-responsive dealer, I need to attempt to fix this myself

My grey tank always shows 1/3 full. It appears to empty without issues, but when it is done, the sensor reads 1/3. Because of this problem and another problem that I am working on, I pulled down the plastic underbelly material to expose the tanks.

It appears that the exit pipe was installed with an uphill slope, probably to the 1/3 sensor level. Basically, I am always carrying a 1/3 tank of grey water.

There is a big metal band clamp that appears to hold the pipe to the tank, but there is also some sort of glue, cement, or pipe joint compound that has oozed out of the joint during assembly.

Does anyone know if this is glue, cement, or solvent, meaning I would need to cut the pipe to do any adjusting, then reassemble with new pipe parts, or is this just a non-permanent paste compound that will allow the pipe to move once I loosen the clamp? Some advice please.

[JFlightRisk]

That would be the ABS pipe cement used to glue the plumbing together. Yes, unfortunately you'd need to cut the pipe to adjust it.

[Grumpy]

Originally Posted by cmikal

I have a new 377RLBH, still under warranty, but due to a non-responsive dealer, I need to attempt to fix this myself

My grey tank always shows 1/3 full. It appears to empty without issues, but when it is done, the sensor reads 1/3. Because of this problem and another problem that I am working on, I pulled down the plastic underbelly material to expose the tanks.

It appears that the exit pipe was installed with an uphill slope, probably to the 1/3 sensor level. Basically, I am always carrying a 1/3 tank of grey water.

Could also be a defective sensor since they are not very reliable. One way to check is pull your passenger side tires up on blocks and see how much more water actually comes out.

[cmikal]

Originally Posted by Grumpy

Could also be a defective sensor since they are not very reliable. One way to check is pull your passenger side tires up on blocks and see how much more water actually comes out.

I can do that, and probably will at some point, but with the drain pipe pointing uphill, I think the problem is mostly or entirely the incorrect slope of the pipe.

[cmikal]

Originally Posted by JFlightRisk

That would be the ABS pipe cement used to glue the plumbing together. Yes, unfortunately you'd need to cut the pipe to adjust it.

I was hoping for a different answer, but I think you are correct. My only reason for asking the question was because of the band clamp. I've never seen a pipe that was cemented or glued, that also used a band clamp. The solvent is supposed to be the seal without any help from a clamp. I also watched a video where a guy replaced a tank and it appeared that he was able to just pull the pipe away from the tank. There was some caulking-type material stuck to the pipe. It definitely wasn't a cement or solvent bond. But the tank appeared to be older and metal, not plastic, and his video sort of breezed through the disconnecting process at double speed without any explanation. So, I was hopeful that newer tanks were assembled with caulking or plumbers putty, similar to what I saw in the video. The band clamp also gave me hope.

[kirkelli]

Originally Posted by cmikal

I can do that, and probably will at some point, but with the drain pipe pointing uphill, I think the problem is mostly or entirely the incorrect slope of the pipe.

follow this video step-by-step and see if it will solve your issues.. Sludge tends to screw up the tank floats and then send erroneous readings,. It's worth a cheap try and it will defiantly clean your tanks out. I follow this recipe every time i empty tanks and never had issues with erroneous readings. Good Luck.
https://www.qwant.com/?client=brz-br...%3AwUWGlm2gQfE

[JFlightRisk]

The OE gray tank sensors on our TT took about 1/2 hour to actually show empty, after dumping the tank. It did show 1/3 until then. Last year it started showing 1/3 all the time, so I replaced the sensors with Horst Miracle Probe sensors. Completely different design, so we'll see if they last another 8 or 10 years.

[OnTheGo]

... maybe another option.

Contact Jayco for the tank manufacturer and you might find the tank on their site (or a distributor's). And hoping for your sake it's a built-in threaded hole and you can start from scratch.

Without seeing it I can't help but agree with you. If your drain pipe slopes up, you probably are not completely draining. Although when I have had the problem it was the sensors that needed cleaning.

[kirkelli]

On another "RVForums" this topic is discussed and many folks have resorted to using the Mopeka water tank sensors and reporting highly accurate results. If i had tank level issues and could not resolve them, i defiantly would try the Mopeka.


https://mopeka.com/product/mopeka-wa...-bottom-mount/

[Parrott]

I installed the Seelevel tank monitor system. Accurate and mounts on the outside of the tanks. Easy install as long as you can get to the tanks sidewall. Here is mine showing 2/3 on the factory and 0 percent on Seelevel and I know it’s empty. Seelevel shows every 3% which is more accurate than factory.

[Parrott]

Originally Posted by cmikal

I have a new 377RLBH, still under warranty, but due to a non-responsive dealer, I need to attempt to fix this myself

My grey tank always shows 1/3 full. It appears to empty without issues, but when it is done, the sensor reads 1/3. Because of this problem and another problem that I am working on, I pulled down the plastic underbelly material to expose the tanks.

It appears that the exit pipe was installed with an uphill slope, probably to the 1/3 sensor level. Basically, I am always carrying a 1/3 tank of grey water.

There is a big metal band clamp that appears to hold the pipe to the tank, but there is also some sort of glue, cement, or pipe joint compound that has oozed out of the joint during assembly.

Does anyone know if this is glue, cement, or solvent, meaning I would need to cut the pipe to do any adjusting, then reassemble with new pipe parts, or is this just a non-permanent paste compound that will allow the pipe to move once I loosen the clamp? Some advice please.

I have removed several black tanks and each one the big black pvc connector that goes into the tank that has the clamp on it will come out once you remove the clamp. It may take some force but isn’t glued in.

[Route 66 Traveler]

Originally Posted by JFlightRisk

Last year it started showing 1/3 all the time, so I replaced the sensors with Horst Miracle Probe sensors. Completely different design, so we'll see if they last another 8 or 10 years.

Are those probes compatible with the stock wiring and gauges? The link to Amazon says the new probes will fit in the existing holes...is that a true statement?

I know I can go 4 days if I start out with empty tanks so I don't pay much attention to the readings I see on the display.

[JFlightRisk]

Originally Posted by Route 66 Traveler

Are those probes compatible with the stock wiring and gauges? The link to Amazon says the new probes will fit in the existing holes...is that a true statement?

I know I can go 4 days if I start out with empty tanks so I don't pay much attention to the readings I see on the display.

Yes, they're compatible with the OE monitor and use the original wire connectors underneath. They fit right in where the old sensors come out. There's a neat YouTube video I found that shows how to easily get the old ones out, so there's no drilling new holes, unless you really want to. They remove the wire and both nuts, use a 9/16" or 5/8" box wrench that fits over the OD of the grommet, and a washer on top of the wrench. And if a rubber piece falls inside the tank, it floats and comes right out.

Here's the video I watched before I did mine. You can skip the first 3 minutes of it if you wish, and get to the part on how it works.

https://www.youtube.com/watch?v=lCHJ1ZF9Usk

[Route 66 Traveler]

Thanks…yes, I think I saw the same video, but the one I saw looked like the sensors were going on the top of the tank and not the sides.

I just don’t relish the thought of removing or cutting through the coroplast underbelly to access the tanks. Plus, I have 2 grey tanks, but the kitchen tank seldom gets much use so I may not change the probes in that one.

I have learned not to rely on the sensors. They work some of the time, and the black tank will show full when it gets close to being full, which doesn’t happen very often.

No doubt it would be a nice improvement.

** That isn’t the same video, but it shows the same procedure to remove the old sensors…

[JFlightRisk]

Yeah, our TT doesn't have the coroplast. I just crawled under, and they're right there on the side of the tanks. As it turned out, there were two sensor wires switched, so the gray tank showed full when it was only at 2/3rds. I happened to look at the wiring on the black tank which was in a different wire color order. Had the DW work the monitor while I grounded the sensors. When I touched the 2/3rds sensor, the monitor showed full. It was that way since new, and found it 7 years later!

[cmikal]

Originally Posted by Parrott

I have removed several black tanks and each one the big black pvc connector that goes into the tank that has the clamp on it will come out once you remove the clamp. It may take some force but isn’t glued in.

I took measurements and discovered that the outlet end of the pipe where it connects to the "Y" at the black tank is at least an inch, and maybe as much as 2 inches higher than the tank outlet. So the sensor is correct. There is 1/3 tank of water that cannot drain out.

Since this is plumbed into a common output dump valve, and everything else except the tank outlet is hard-glued together, I would need to raise the grey tank to get it into the correct position to have any hope that it would drain correctly. OR, I would need to cut the pipe, cap it at the "Y", and run a new pipe for a new (second) dump valve at the side of the RV. This would be the simpler, easier option IMO, at the expense of having 2 dump valves.

I am going to contact Jayco and see if I can get a resolution through them since it is still under warranty. The issue is that I can't drop this off at a dealer and wait for weeks or months for them to get around to looking at it. I am on the road and won't be in a position to even drop it off for a few days until December.

Anyway, thank you for the info regarding being able to separate the pipe from the tank. I may need to do it if I can't get help from Jayco.

[16WhiteColly]

Originally Posted by JFlightRisk

The OE gray tank sensors on our TT took about 1/2 hour to actually show empty, after dumping the tank. It did show 1/3 until then. Last year it started showing 1/3 all the time, so I replaced the sensors with Horst Miracle Probe sensors. Completely different design, so we'll see if they last another 8 or 10 years.

We’re the old sensors hard to remove?

[Trailerhack]

I have a 154bh with the same problem... pipe sloped upward... when dumping tanks I raise opposite side of trailer with 5" of blocks under wheel... only way it empties completely. With only a ridiculously small, 8 gal black tank, it needs to be completely emptied.

[Retired mountain folk]

You may just have some food or some sort of liquid caught on the sensor. I know most coaches have the sprayer inside your black tank. You could always install one on your grey tank,, hook to a hose. We did that on our coachmen and it then showed empty. . Ours used to show 1/3 right from new. Or Fill up the grey tank, add some dish soap, drive around so it’s swishing the sensor, empty and hope that takes care of it, ours didn’t, hence the installation of a sprayer…. Good luck

[Nature Ist]

You are not the first to discover the drain pipes pitch the wrong way. I have the same problem on my HT fifth wheel with three tanks. The rear gray tank 1 1/2" ABS drain has two issues: 1st, the 3" reducer to 1 1/2" was installed so the reduced outlet is not at the very bottom of the 3" opening; 2nd, the drain runs rearward, then turns 90 degrees to the side before another 90 degree turn forward to the main waste outlet. Because the tank is a center drain, pitching the camper to the side does not help, neither does pitching it rearward. My best solution has been to install a gate valve at the dump connection. With that gate valve closed and the waste tank valve open while driving I do get more of the gray water to drain forward.
I have removed the entire coroplast underbelly and investigated my options: there really are none! I cannot get the amount of pitch in the right direction without removing everything and rerouting it all.
Its interesting to note that these units are assembled when the frame is upside down at the factory - it's no surprise the installers cannot judge what is up or down! Nor is it a surprise they couldn't care less! So we deal with the consequences. I'm just glad there isn't enough liquid in that pipe to freeze solid and rupture the waste-line in our cold winters.