Black tank removal on 2000 Excella 34

[coolbikeman]

I am not sure if I want to attempt this as I am full time in the trailer and have limited tools. Have an odor coming from a hole in floor behind toilet that lets drain pipe from sinks run along top of floor and connect to grey holding tank below. I have checked vents for obstructions. Don't see any leaks on outside of pan covering holding tanks.
Does anyone have experience with this model trailer? I need to know if the toilet pipe screws into black tank or if it is glued, same for vent pipe. Can I take floor flange loose and unscrew pipe to black tank in order to see top of tank from inside of bathroom for any cracks that might be letting gas odors escape If I do drop the pan covering tanks, it appears that the pull handles for valves have sheet metal plates riveted to side of pan I am assuming to allow access to get the pull handles out of the way in order to drop the pan.

Thanks,

the "coolbikeman"

[CRH]

My toilet flange has a short piece of pipe on it that is clamped in the tank neck.

To service the dump valves, my Airstream manual calls for cutting a hole in the belly pan, doing the work and them putting on a cover plate. That is exactly what I did when mine needed attention.

[coolbikeman]

Thank you for responding. How do you access the clamp for pipe connecting to black tank? Is there enough room to loosen it from under trailer? Or, will the toilet flange unscrew from the short pipe which I can access from bathroom?

Thanks

coolbikeman

[CRH]

My toilet is probably different from yours....Mine is a short toilet that sits on a wooden pedestal....basically a box. It has a removable panel in the front that allows access under the toilet. My flange is glued to the short pipe.

[n2916s]

My toilet flange screws directly into the top of the tank at floor level. You remove the toilet and the black flange unscrews. At least on mine, there is no "pipe" between the toilet and the tank.

[coolbikeman]

Thanks again. You are correct my flange mounts directly to the floor with a short pipe maybe 3 or 4 inches long a most going into the black tank. Somehow I think it must be unscrewed before the black tank would be able to drop. Just by looking through the hole in my floor where I can see the grey tank there can't be more than an inch or inch and a half distance between the tank and floor.

[coolbikeman]

Have you unscrewed the flange? Just wondering if it was difficult to do and whether there was any type of thread sealant( pipe dope ) on threads?

Thanks

[fwjumper]

Remove the screws holding the flange to the floor. They will be rusty and may break or be difficult. Once that is done, unscrew the flange from the tank fitting. Yes, there should be some thread sealant and depending on whether or not it has been "serviced" before, there could be other sealants about. Sometimes you need to use a big screwdriver or something with a blunt end and a hammer to tap the flange in a counter clockwise direction to get it moving. You can get a new flange, but you may have to order it or go to a plumbing supply, depending on what's there. The fitting in the tank itself should be just below the subfloor level. You won't be able to see much of the top of the tank.

One last thought. Is your toilet holding water in the bowl after you flush it? If not, that's the source of your odor. If there are no leaks to the ground, I doubt if you have a leak in a tank.

[coolbikeman]

Originally Posted by fwjumper

Remove the screws holding the flange to the floor. They will be rusty and may break or be difficult. Once that is done, unscrew the flange from the tank fitting. Yes, there should be some thread sealant and depending on whether or not it has been "serviced" before, there could be other sealants about. Sometimes you need to use a big screwdriver or something with a blunt end and a hammer to tap the flange in a counter clockwise direction to get it moving. You can get a new flange, but you may have to order it or go to a plumbing supply, depending on what's there. The fitting in the tank itself should be just below the subfloor level. You won't be able to see much of the top of the tank.

One last thought. Is your toilet holding water in the bowl after you flush it? If not, that's the source of your odor. If there are no leaks to the ground, I doubt if you have a leak in a tank.

Thanks this is just the info I needed. The toilet does hold water fine. Does the toilet flange have a short pipe glued to it? Either the flange is extra deep or mine has a short pipe connected to it. I will have to see if I can find a picture of a new one online.

[fwjumper]

From the top of the flange to the bottom of the male threads is probably between 3 and 4 inches. If everything is still original, that should be the setup. The threads are long enough to reach through the flooring and screw into the fitting on the tank. So no, there isn't really any pipe in the mix, but the threaded section is probably what you are thinking of. Maybe 2.5"

https://www.etrailer.com/RV-Sewer/Va...All%20Products

[coolbikeman]

Thanks fwjumper, that flange is probably what I have. I have to decided whether I can get under trailer. I have no pavement under it and I would probably need to use jack stands to raise it up. I have checked a couple dealers and it would take a lot of time with the labor costs around $130/hr

[aswell]

We replaced the toilet in our 2000 34' with an Airhead composting toilet. Rather than attempting to remove the flange, I opted to install a 3" plug, in case we decided to go back to a standard toilet later.

One way to test for the source of the leak might be to install a plug, and see if you still have any smell...

[coolbikeman]

Originally Posted by aswell

We replaced the toilet in our 2000 34' with an Airhead composting toilet. Rather than attempting to remove the flange, I opted to install a 3" plug, in case we decided to go back to a standard toilet later.

One way to test for the source of the leak might be to install a plug, and see if you still have any smell...

I don't know much about composting toilets or how they work in a trailer. But your installation looks great. You did a nice job. At least I would have another option.

Thanks for your information.

[aswell]

Originally Posted by coolbikeman

I don't know much about composting toilets or how they work in a trailer. But your installation looks great. You did a nice job. At least I would have another option.

Thanks for your information.

Surely, and thanks. Was my first time installing wood flooring, ripping up glued down bath tiles, removing a partition wall, and so forth, but it turned out ok in the end.

If your tank is toast (or even if it's not), composting toilets are worth exploring. They are not for everyone, but it's worked well for us.

[A W Warn]

Originally Posted by coolbikeman

I am not sure if I want to attempt this as I am full time in the trailer and have limited tools. Have an odor coming from a hole in floor behind toilet that lets drain pipe from sinks run along top of floor and connect to grey holding tank below. I have checked vents for obstructions. Don't see any leaks on outside of pan covering holding tanks.
Does anyone have experience with this model trailer? I need to know if the toilet pipe screws into black tank or if it is glued, same for vent pipe. Can I take floor flange loose and unscrew pipe to black tank in order to see top of tank from inside of bathroom for any cracks that might be letting gas odors escape If I do drop the pan covering tanks, it appears that the pull handles for valves have sheet metal plates riveted to side of pan I am assuming to allow access to get the pull handles out of the way in order to drop the pan.

Thanks,

the "coolbikeman"

If you have not already, I suggest taking the toilet up and checking the foam gasket that seals between the flange and toilet. On my 1999 34' that gasket was hard, cracked, and did not seal, allowing odor to escape. It was especially noticeable when the exhaust fan was on. This replacement can be done in an hour; disconnect the water line then remove two nuts from the flange bolts that hold the toilet to the toilet flange. One bolt on the left side, when standing in front of the toilet. The other bolt at the pedal opening. Once the nuts are removed the toilet lifts straight up. Only tools I needed was open end and boxed end wrench to fit the nut.
https://www.amazon.com/Thetford-3323.../dp/B000BGM7QS

I've had the toilet out of my trailer two times since I owned it. (sorry, no photos)
And, I've replaced the dump valves on both gray and black tanks. You can see my posts>
http://www.airforums.com/forums/f444...es-162941.html

ps:
I also replace all the seals in my toilet using Thetford kit 08369, that I got at Out of Doors Mart.
https://www.rvautoparts.com/08368-Th...yABEgIrI_D_BwE

[coolbikeman]

Originally Posted by A W Warn

If you have not already, I suggest taking the toilet up and checking the foam gasket that seals between the flange and toilet. On my 1999 34' that gasket was hard, cracked, and did not seal, allowing odor to escape. It was especially noticeable when the exhaust fan was on. This replacement can be done in an hour; disconnect the water line then remove two nuts from the flange bolts that hold the toilet to the toilet flange. One bolt on the left side, when standing in front of the toilet. The other bolt at the pedal opening. Once the nuts are removed the toilet lifts straight up. Only tools I needed was open end and boxed end wrench to fit the nut.
https://www.amazon.com/Thetford-3323.../dp/B000BGM7QS

I've had the toilet out of my trailer two times since I owned it. (sorry, no photos)
And, I've replaced the dump valves on both gray and black tanks. You can see my posts>
http://www.airforums.com/forums/f444...es-162941.html

ps:
I also replace all the seals in my toilet using Thetford kit 08369, that I got at Out of Doors Mart.
https://www.rvautoparts.com/08368-Th...yABEgIrI_D_BwE

Thank you for all the information. The pictures of the black and grey tanks are helpful. Now I know what they look like under the pan. A few questions:

If I need to drop the pan did yours come off easily? Just wondering if bolts hold it on came out without breaking. Oh, never mind you didn't drop the pan.

I probably should replace the valves if I do drop it. It looks like the valves don't just unbolt and are replaced. You mentioned them being glued to an adapter, is that correct?

I have had my toilet up several times. I don't think the seal is leaking since it is new but I am worried that because I installed a thin( 3/16" thick) mosaic tile floor maybe it is keeping the toilet from compressing the gasket by that much. A technician from the Bill Thomas Airstream dealer in Missouri suggested filling black tank up until water comes above floor and causes pressure to see if anything is leaking from the pan. It may let me know if the toilet gasket is leaking also.

Without dropping the pan I can't be sure what is causing the odor. Could be a crack, valves leaking, tank vent not sealing good, or black tank flush not sealed good.

Thanks for your help. The pictures you posted are very helpful

[A W Warn]

Glad to help!
See my comments inserted in RED

Originally Posted by coolbikeman

Thank you for all the information. The pictures of the black and grey tanks are helpful. Now I know what they look like under the pan. A few questions:

If I need to drop the pan did yours come off easily? Just wondering if bolts hold it on came out without breaking. Oh, never mind you didn't drop the pan.
I've dropped the pan on other trailers. I have had all bolts come out easily. But I have read reports from others that said theirs broke of due to rust. I believe this is related to how much salt the trailer has been exposed to and the age of the trailer.

I probably should replace the valves if I do drop it. It looks like the valves don't just unbolt and are replaced. You mentioned them being glued to an adapter, is that correct? On my 99, the adapter slips into the tank and is sealed with caulk and is clamped around the perimeter of the tank coupling. Then the valve is bolted to the adapter and sealed by compression of a rubber o-ring. Then the sewer pipe is glued directly onto the valve.
My advice is to replace the adapters and valves before there is a real problem. The plastic parts of mine were brittle and cracked. The rubber seals inside the valves were hard. In order to replace the adapter and valve, the pipe and fittings are sacrificed. I re-used only the rubber coupler and stainless steel clamps.

I have had my toilet up several times. I don't think the seal is leaking since it is new but I am worried that because I installed a thin( 3/16" thick) mosaic tile floor maybe it is keeping the toilet from compressing the gasket by that much. This is probable!!!! A technician from the Bill Thomas Airstream dealer in Missouri suggested filling black tank up until water comes above floor and causes pressure to see if anything is leaking from the pan. It may let me know if the toilet gasket is leaking also. This is good advice, test before dropping the tank cover. There is not a lot of compression depth in that Thetford gasket. You might have to double the thickness or find another type/brand that is thicker. I've seen some that are about 1" thick foam rubber, but do not know which brand.

Without dropping the pan I can't be sure what is causing the odor. Could be a crack, valves leaking, tank vent not sealing good, or black tank flush not sealed good. Even if you drop the pan, you cannot see the top of the tank until you remove the tank. Test first! .

Thanks for your help. The pictures you posted are very helpful

[coolbikeman]

Originally Posted by A W Warn

Glad to help!
See my comments inserted in RED

Thanks for the advice.

[coolbikeman]

Originally Posted by A W Warn

Glad to help!
See my comments inserted in RED

I forgot to mention my rant about how Airstream puts together some of their trailers🥺. I cannot understand why Airstream would use this method to connect the valves. Looks like it causes a lot more work and money just to replace them. I had a 2002 Holiday Rambler before our Airstream and it was just a matter of unbolting the valve and putting a new one in. No gluing or having to replace parts.

I am also wanting to replace the electric heating element and thermostats for the water heater and I found out the water heater has to be removed to access the back of the water heater where the element is located. Not looking forward to that either.😕

[coolbikeman]

Update of my holding tank repairs