[A/S] Thetford toilet question

[SHMossLanding@xxxxxxx]

Can anyone tell me about a vintage Thetford toilet.  Ours developed a leak in 
the gasket between  the bowl and the slide unit. I disassemblied it cleaned 
all the parts, and reassembled.  I put water in the bowl, as a test before I 
installed it  I have discovered they do not make parts for these toilets 
anymore.  I have water leaking from the bowl, past the slide and into the 
tank. My question is, are the bowls supposed to hold water for a period of 
time, or do they empy themselves, so you don't have water sloshing around 
while your traveling.  Any help would be appreciated.

             Chuck & Lynn
             1965 Overlander