Remodeling my RV wet bay started with a leak in my black tank. After fixing the leak in my RV’s black tank, I have remodeled the entire RV wet bay. It was a long and involved process with several steps along the way. If I haven’t mentioned it before, but nearly a year later, I am convinced the RV black tank repair was 100% successful.
Unlike most of my articles, this one contains a rant, but don’t give up before the happy ending.
The first repair to our RV black tank failed.
I was concerned when I tested the repair (the same day they gave me the RV back), only to find out that the technician had failed to glue all the sewer pipe joints when he put them back together. Did they think I wouldn’t immediately test the repair? Perhaps they didn’t know I would tell you about it even though I gave them my card and website address.

Testing for leaks after the repair.
After the shop returned the RV, I went straight to our campsite and did yet another leak test. The first step was to use the black tank sprayer to partially fill my brand-new black tank well above the connection to the dump valve to ensure no leaks from the bottom of the tank or connections leading to the dump valve.
I think I was repeating the same test the shop performed before they gave me back the RV. The only difference between my test and their test is they dumped the water on the ground after their test. I knew that a partial test was not good enough. I needed a fix that wouldn’t leak anywhere from the black tank, not just from the lower part of the tank.

So, using a hose running into the toilet, I filled my new black tank to the very top of the black tank, including the new sewer pipes under the toilet. This would prove that I had a good repair. If my black tank system would hold water into the stack and under the toilet, I would be satisfied with the repair. My brand-new tank installation failed the test and leaked from the pipes under the toilet. I can’t believe the technician didn’t glue the pipe fittings between the black tank and the toilet. Thankfully, un-soiled freshwater leaked during my test, not sewer water.
The following morning, I was back at the repair shop. To fix the new leak, they had to remove the toilet again and all the pipes under the toilet so that they could reassemble them, this time using glue at every joint. After they were done, I returned to the campground and tested it again. This time, the RV black tank repair passed the test. The shortcut during the repair led to a long detour and some serious backtracking.
Getting ready for the repair.
My previous article outlines how I had to remove the beauty cover in the RV wet bay and find the leak myself before the RV shop would take the job. It also outlines why my repair was going to be very difficult. Until the RV shop removed and replaced my black tank, I had already invested days of labor and two hundred dollars into finding the leak and disassembling the RV wet bay. Last year’s article was dedicated to finding the leak in my black tanks and finding a shop that would repair it. Here is a link. Fixing our RV Black Tank Nightmare

Our Extended Warranty
My extended warranty company was a pain to work with, but it eventually covered some (most) of the costs associated with the repair. Working with my extended warranty company slowed the repair, as did shop scheduling and shipping my new black tank. Now, after two repairs, we have almost covered the cost of our extended warranty.
I hope nothing else happens, but it won’t take an extensive repair to break even on the warranty price. I like to link to companies that help me during our RV journey. They won’t get a link in this article even though they helped. They act like dogs with food aggression, hovering over the food bowl and growling. Like most extended warranty companies, they made the process difficult. While they helped, they tried to save money by not paying for the required items needed for the repairs. I want to acknowledge they did their job despite being slow and difficult for me to work with.
In the end, since the RV black tank specialist didn’t want the job in Quartzite, the warranty company didn’t pay for the claim to find the leak because the specialist who found the leak didn’t want to repair it.
Lots of do-it-yourself labor
It would have been far more costly without my do-it-yourself labor. Neither the RV shop nor the warranty company would take the job until I could prove it was leaking and show them where it was coming from. First, I had to tear “everything” apart in the RV wet bay to get photos of the leak.

I had to live with the RV wet bay torn apart for months, waiting for a new black tank to be delivered. After scheduling the repair with the shop and getting approval from the warranty company. Only then could the shop fix the RV wet bay and get me back on the road. Even then, the repair shop put it back together the way they found it without re-installing the things in the RV wet bay that I removed to get the pictures.
Not reassembling the RV wet bay.
Perhaps I could have reassembled everything in the RV wet bay before the repair shop started the job, and then the repair shop would have had to take it all apart when they replaced the black tank. Then perhaps the repair shop would have reassembled the RV wet bay as it came out of the factory.
Taking something apart and then reassembling it just so someone else could take it apart is stupid, so I didn’t put it back together. Not putting the RV wet bay back together saved the repair shop’s labor time and the warranty company money. I vowed to make the RV wet bay better than Tiffin’s design, even if it wasn’t the same as the original design.

What I found when I first removed the cosmetic cover in my RV wet bay was embarrassing and shoddy. I don’t assemble RVs, but I knew I could do a better job than the factory. The stuff in my RV wet bay is just plumbing and low-voltage wires. Remodeling my RV wet bay allowed me to redeem about twelve cubic feet of unused, wasted storage space. Finding hidden storage space in an RV is very valuable.
Addressing the rat nest of wires in my RV wet bay.
Tiffin gave me more than one rat nest of wires. Perhaps I haven’t found the worst one, but this one was pretty bad. One benefit was I had plenty of time to clean it up. I had to clean up this mess to get my head far enough into the RV wet bay to find the leak.

You can see from the above photo that two wire bundles were tied together to make different systems work in the RV. Some wires were used for the freshwater pump and tank level sensors, and others powered different components, like the hose reel in the RV wet bay. Have RV manufacturers ever heard of a bus bar? (A bus bar is a collection point for wires that need to be connected at one point.) Honestly, I am unsure what some wires do; they go to some unknown destination. But I cleaned it up, and now it is better. This photo was taken well before I was able to find the leak.

Continuing my rant about RV manufacturing… Do I think that RVs built recently are better built than my RV? There is no way the newer RVs are better than my older RV. The objective is still to build RVs with the most profit. Everything is about making them look better. The objective is not to do things the best way. If you find a rat nest of wires, it is okay if it is hidden behind a cosmetic cover. Shame!
Photo of our leak
I sorted out and organized all the wires in the RV wet bay, and only then was I able to get a photo of our leak. It was challenging to accomplish. Even today, I have never seen the top of my RV black tank in person. The leak was under the toilet between the frame rails at the intersection between the sewer dump pipe and the black tank. To get the photo, I had to fill the tank, put my cell phone above the frame rails, and use a voice command to take the picture.

My repair shop
My repair shop was northwest of Tucson, Arizona, and I will not provide a link to them either. I am happy that they fixed the leak. I will describe how my repair shop performed the repair compared to how I learned that Tiffin and other repair shops in Red Bay, Alabama, near the Tiffin factory, would have repaired it. Before I assigned them the job, they assured me they made several similar repairs in the past. Perhaps they have, and maybe I didn’t get the experienced technician.
The passenger side of my RV.
To understand the repair, the following photo is of the holding tanks on the passenger side of my RV, and the tank(s) need to be extracted from this side of the RV. I have found another rat nest of wires, pipes, and another example of shoddy design and workmanship.

How would the repair shops in Red Bay have removed my black tank?
I have friends in Red Bay who provided the procedures. These steps are not in a specific order because in Red Bay they work on both sides of the RV at the same time using more than one technician.
On the passenger side of the RV
- Remove the overflow pipes from the freshwater tank.
- Remove the black tank flush hose connection.
- Remove the steel frame from the top of the freshwater tank to prevent the black and grey water-holding tanks from shifting. This steel frame sits on top of the freshwater tank! Really? Who designed this?
- Cut and bend the frame around the door enclosure at the bottom and sides to allow room for the freshwater tank to slide out towards the passenger side of the RV.
Inside the bathroom
- Remove the toilet and toilet flange, and if possible, remove the stack between the black tank and toilet flange by pulling the stack up and into the bathroom, assuming the flange is completely broken at the top of the black tank.
Inside the RV wet bay on the driver’s side
- Dump all fluids from all the tanks, being extra careful to clean out the black tank as well as possible.
- Cut and remove the pipes from the freshwater and black tank.
- Push the freshwater tank out from under the black tank towards the passenger side.
- Drop down and push the black tank out towards the passenger side.
During reassembly, the black tank fittings are assembled on the new tank before sliding the new tank into position. Then, the black tank is raised and supported from the bottom. The final step for the black tank is to glue the final pipes together under the toilet before putting the fresh water tank under the black tank.
Here is another photo of my leak after the black tank was fixed. It is obvious that this picture, compared to the following one, was missing the glue at the pipe joints.


Even though I gave them instructions from Red Bay, my repair shop ignored everything about removing the fresh water tank. They removed the black tank by sliding it out with the fresh water tank still under the black tank. This means the pipes between the toilet and the black tank were installed after the new black tank was in position. As you already know, they assembled the stack under the toilet without gluing the parts together. They made the assembly all by reaching down to the new black tank through the hole under the toilet. The pipes didn’t get glued together until I returned the next day.
Before the repair, I told the service manager I wanted the new flange (already installed while manufacturing the tank) to be reinforced with silicone glue. What I intended and what I got are two different things. I expected enough glue so that if the flange were to crack at the junction, the glue would hold everything together, preventing a leak. The “after” picture shows some sealant (white), but it is in the wrong place, and I wouldn’t describe it as ample. After it is installed, it is the wrong time to fix it, so now I have to live with it.
Even though I gave them a list from Red Bay about the suggested procedure to remove and repair the tank, they were trying to increase profits by cutting corners. Their corner-cutting cost them an extra day of labor fixing their mistakes. Of course, they would have succeeded in cutting corners if I hadn’t tested the repair.

As a final failure, even though they charged me for a new sensor stip to transmit the tank levels to the display, they instead tried to harvest the old sensor off the old tank. They broke the wires on the sensor strip, and it never worked. It still burns me that they charged me for a new sensor strip but instead tried to use my old sensor strip. The sensor strip was not new when I took the passenger side of the tanks apart to try and find out why it didn’t work. It took a few more days to find and install a new sensor strip, and everything worked. Amazing.

It took a while before I got my refund for the sensor strip from the repair shop. It took even longer for me to get reimbursed from the warranty company.
How much did the repair cost?
I don’t usually post prices, but I think it is germane. The total cost for our repair at the shop was $3600, including the sensor strip price. To this total, add a price for one night in a hotel. It does not include the cost associated with the cosmetic cover on our RV wet bay or the fee paid out of pocket to identify the source of the leak. The price for the repair in Red Bay would have been similar, not including the cost of driving to and from Red Bay or the other expenses along the way.
Perhaps I should have driven to Red Bay for the repair. I am sure I would have a better RV today if I had done that, especially if they allowed me to help during the repair.
The repair was beyond what I could do in a campground, but I wish I could have repaired my black tank despite the yuck factor. I know that I would have done it like in Red Bay, and I would have reinforced the flange with lots of glue (and perhaps some wire cloth) to ensure this would never leak again from that location.
Remodeling my RV wet bay after fixing my black tank leak.
Before fixing the leak in my black tank, I had already fixed most of the wire problems in my RV wet bay. The next step was finding a place to put my terminal block (that is what I call it) as far away from the door as possible. I wanted to reach the terminal block board if I needed to work on it, but I also wanted it to be as far away as possible to use the space above the black and grey tanks for storage.

We have three switches (one next to each sink and one in my RV wet bay) to control our pump, and I mounted the latching controller on the terminal block. This latching switch is a relay that turns the pump on or off when I depress the pump switch. If you have multiple switches (spring loaded) and the pump fails, this latching switch is probably faulty. Mine is out of the way, but I can still reach it instead of burying it behind the cosmetic cover. If this latching controller fails, I will glue the new one on top of the old one and transfer the wires.

To move the board, I had to find a location where my tank sensor monitor and water pump on/off switch could be placed in a place that was easy to reach. I did all the electrical remodeling before working on the plumbing mess in the RV wet bay.

Removing all the freshwater pipes and valves
To reclaim the extra 12 cubic feet of potential storage in my RV wet bay, I had to move all the freshwater plumbing that was in the way. I didn’t do this until after I finished all the electric changes in the RV wet bay and was satisfied that all the wires were in the right place, both out of the way and yet reachable. The following photo was of my freshwater pipes and valves; I removed them all as one piece.

Freshwater fill in our RV wet bay starts at our hose reel and then goes through a few valves to our filter and water softener. After returning from the filters, the water softener goes into our freshwater tank. If the valves are correctly configured, they will go directly to our water distribution system. Here is a link discussing our filter and water softener. Super-Sized RV Water System

Not using city water pressure.
Unlike many (perhaps most) RVers in campgrounds, we rarely use city water pressure and instead send all the water first to our freshwater storage tank. The reason is that I want the water in the storage tank to be as fresh as possible and still contain the necessary chlorine to keep us healthy. Thus, I never (even though I could) let the water in our freshwater tank get old because I was too lazy to fill the freshwater tank. I don’t think opening a valve and filling the fresh water tank every few days is too much labor. We drink water from our freshwater tank and RV plumbing system.

A second reason we use the water out of our freshwater tank is to exercise our water pump frequently. In the following photo, you may have noticed that I rotated the pump and connected it to the plumbing system using a hose. You may have missed that I mounted the pump on flexible foam. My pump is no longer bolted to the floor of our RV wet bay.

Black tank cleaning
To help describe the black tank cleaning system, I will reuse a photo and diagram from earlier in this article.




Our RV wet bay storage shelf.
Once I removed the rat nest of wires and pipes running across my RV wet bay, I made a shelf across the RV’s black and grey tanks. I used a large sheet of textured black plastic and a heat gun. On a picnic table, I softened the plastic enough to bend it. Once installed in the RV wet bay, I no longer had to look at the storage tanks.

Conclusion
Accessing 12 cubic feet of extra storage space above our RV wet bay is a vast improvement. In the following photo, I put one of my storage boxes holding my sewer hose on the shelf and have room on both sides for other smaller boxes.
What is next in my RV wet bay?
It is part of my remodeled RV wet bay but doesn’t pertain to replacing my RV black tank. The basin below the wet bay is worn through and has holes in the bottom. As it kicks up rocks, the front tire has left the basin at the bottom of our RV wet bay beyond repair. I have found a replacement box at IKEA and will replace it soon enough.

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About our links
As you know, our blog income is zero, which allows us to be independent and tell the truth. We do not get income or commissions. No, we don’t make paid endorsements. We don’t make recommendations; instead, we will tell you what we like (or dislike). The links are only provided as a quick reference to help our readers.
Links
FoxRVTravel article: What is in your RV Black Tank?
Thetford Black Tank Spray nozzle
Wago spring-loaded connection blocks
Recreational Vehicle Industry Association
I included this link to the Recreational Vehicle Industry Association to point out that these people are supposed to help establish standards and best practices for RV manufacturing. Most RVs have a little sticker beside the door stating that the RV meets the standards. Their standards are very low. I hope you might email the RVIA when you find a rat nest of wires like the one I found in my RV wet bay. I have to caution you, however, that there are no standards except as desired by the manufacturers, and any emails about the quality of RVs will probably get ignored.
About the missing links about my shop and warranty company. I’ll let you know who I wouldn’t do business with again, but not in the blog.
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Wow! What a job. But things look great now. So, I wonder if the guys who cleaned your tank created your problem. I saw a video of how the hose they slide up into the tank raddles around and bangs up against things from the pressure they are using. I wonder if that broke your joint. This is another example of how knowing how to do things is beneficial. Repair guys hate people who question what they do. Repair people have taken so many shortcuts on my new rig it will take months to fix things correctly. Wet bay looks very nice.
I watched the tank cleaning process. They didn’t let the hose bang around inside my tank. Yet, I won’t be doing another cleaning due to the risk of using a pressure washer to clean the inside of my tank.
Hi Scott,
Great write-up. Thanks for including the steps that Tiffin uses for the job. I need to replace tanks on my 2005 Tiffin Allegro Bus. Where did you get the replacement blank tank? My fresh water tank is partially collapsed and last summer I discovered that either my grey or black tank leaks when full. I may have the same problem that you had. I think you have given me enough info to tackle the job myself.
Thanks for the great blog.
My replacement tank came from Tiffin. Shipping can be an issue; the first tank delivered was damaged during shipping, but the second one was good. The tanks are made in Red Bay, which is another reason to get the repair done there. If you replace the Grey and Black tanks because they are leaking, and since you have to pull out the fresh water tank anyway, I think I would spring for a full new setup.