Toilet->Black holding tank connection

[mendosoft]

Info: 1975 22' Argosy rear door, all original toilet/tank system as far as I know.

I think we need a new toilet discharge seal between the bowl and the black tank. When I pre-fill the toilet w/water and let it sit, it slowly drains out suggesting the seal isn't tight. And we may have some odor as well - again, indicating a possible seal issue.

A few ?'s:

1. Is there some kind of seal/gasket/??? in this coupling?
2. Should the seal be 100%, thus holding the pre-fill water?
3. Is the repair easy? I'd imagine it might not be pleasant due to the need to deal w/the black holding tank...

Any other insight is appreciated.

Steve/Les/Sophie

[Argonaut20]

There is usually a foam seal that the toilet sets on. After 36 years it has likely lost some of that pliability so necessary to doing the job. Get the type of toilet you have in case there are different seals, then get the seal at your local RV parts supplier.

If you run water through the toilet enough to flush the tank out, the whole process is not bad. Remove the toilet by disconnecting the water and removing the nuts that hold it down to the fitting on the top of the tank. The toilet pulls up and off. The seal may be stuck to the bottom of the toilet or stuck to the top of the tank. Take the old seal off, fit the new seal, put the toilet back down, put the nuts back and screw the toilet down. Connect the water and check for leaks.

I kinda wondered if the leak was the seal or the knife valve in the toilet.

[mendosoft]

Yeah, I think I may have misspoke a bit. I think the issue is what you call the knife valve INSIDE the toilet rather than the seal from it to the tank.

If I fill the bowl w/water and wait a few minutes, the bowl is empty - which seems to indicate the knife value (?) that opens when you flush the toilet. I think that's where the leak is, and I can only assume it shouldn't leak at all - in other words, the bowl should hold water until flushed...

TIA to all.

[richinny]

try this thread for ideas:
http://www.airforums.com/forums/f446...ter-43441.html

[overlander63]

Just for you to consider...
What you have is a 30+ year old plastic toilet that has had God knows how many, and how much, and of what, placed in on and around it.
It would probably help the "feel" of the bathroom to get a new low-profile toilet, and put it in. You are going to have to take the old one out to reseal it, why not just put in a new john, and be done with it for years?

[driverjohnlh]

You might try the coat hanger first. Just clean out the groove the knife blade sets in. Cheap and easy, it fixed mine. Then give all users the "proper flushing instructions".