Originally Posted by noralee
I've checked and cleaned the vent and I am still noticing an odor outside mostly. Would this mean that the black tank seal may be compromised?
H'mm, if the black tank seals (there are only 3 seals in the tank) were compromised, you should see some kind of leakage. The 3 seals are:
1. The toilet floor flange. The rubber gasket that is between the toilet and the tank flange on the floor. If that leaks, and it can, you should see some staining maybe at the floor tile at the base of the toilet. Or it is running under the floor, and you may not see it but you can sniff to smell the leaks there. Was a new RV rubber toilet seal put in when the new RV toilet was installed? We are assuming an RV toilet here, if that is not the case please let us know.
2. The black tank vent pipe to the black tank seal. The pipe from the roof drops down and is connected to the tank. I am not sure how Sunline did this tank connection back in the 80's. The newer Sunlines have the vent pipe solvent welded to the tank fitting. A cracked pipe fitting is possible, odds are low but not impossible if the tank was dropped out sometime in it's life. but there is no rubber seal in this case as the fittings are all welded together.
There is another way tank vent pipes attach to black tanks, they use a larger rubber grommet seal. The pipe is inserted into the grommet and the grommet into the tank. That rubber seal could go bad in 30 to 40 years. But, again I have no idea if Sunline did the old campers that way. Sunline Fan may know as he has his 80's camper totally apart and the tanks all out of it. He would of had to deal with that tank vent pipe.
3. The last seal is the tank dump valve. They do leak when paper or other debris gets jammed into the sliding blade seal or the rubber seal cracks and goes bad over time. If this was happening, the liquid in the tank will drain itself out into the sewer. And If I recall, yours is hooked up to a septic tank system. If you look down the toilet and there is no liquid left and the valve has been closed for a several days, then this seal may have an issue. This also is assuming your septic pipe has a good seal to the camper tank dump pipe. But again leaks to the outside of the piping leaves tracks of liquid on the ground, so you can see it. Did you look under the camper for any leakage?
A few questions on how you use the black tank as your semi permanent campsite has a sewer connection all the time.
Do you leave the dump valve closed, use some starter water in the bottom of the toilet and then when the tank gets full enough, open the dump valve drain it out, and dump some 3 to 5 gallons of water down the toilet to help rinse out the tank? A black tank never rinsed can have a build up in it.
I do use the Happy Camper but we dump and rinse the tanks clean after every campout. We have internal tank sprayers where water sprays inside the tank to flush it. So I do not have to dump water down the toilet to flush. We have been doing this since 2004 and hundreds of campouts and never had smell issues inside the camper when flushing or outside the camper. When at the dump station, there may be a time or two we get a whiff of stink when dumping. After flushing the tanks, there is no smell.
Do you have a fan in your bathroom, and is it ever "on" when you flush the toilet? If the fan is on, it can draw up tank fumes when you flush. Just shut the fan off to flush then turn it on again if you use one.
Hope this helps. Some feedback on the questions may help send us into a better direction to troubleshoot with. And especially if the liquid is draining out of your black tank between dump'ings.