Magic IV Toilet sealant

NO Thetford IV manual(foot/hand) RV toilet has a "float". The water valve just opens and water flows into the bowl reservoir tank and then into the bowl. The point is to prevent excess pressure/water volume from spewing out the bowl fill tubes running out the top of the seat area onto the floor. Think of it as a regulator. IF you are talking about the top half and bottom half that is secured with about 8 screws then you just use Butyl to seal and then trim the excess off. There is no reason to disassemble unless you needed to do a thorough cleaning of the base assbly. Doug

PS, Yes, Butyl will do for the Flush tubes over the nozzle ends.

Very interesting design. So it looks like if the flush/ overflow tubes leaked they would just drain down to the black tank instead of running over the floor. Genius.

How does the tank regulate pressure? I'm a little confused.

I did do a thorough cleaning as there were 2000 dead fly larve in that "airspace". Can all those moving parts be replaced without dissembling the two halves?

With this "two piece" design if full enough, is it possible the black tank could "slosh" forward and up into that area? Guessing maybe that's how it became so dirty.

Depends on how close the top of the Black tank is to the toilet floor flange. Regulator was a poor choice of words. It just goes from the water valve to that Reservoir, then to the fill hoses. Do you use or use enough Black tank chemical? Doug

Yeah I have to throw some in there more often.

WOW what a pain putting this toilet back together. Getting that arm aligned into the hole with the spring, etc.

I started joining the seat edge end first together before the tank end pressed into the butyl. (I was trying to get them to join simultaneously).I'm afraid it shifted slightly before the tank end pressed together.

How forgiving is this butyl? I started working with an IMMACULATE mating surface but I actually had to separate it once and then put it back together again (repacked the groove flush with butyl but didn't completely clean). I'm worried there might be a leak.

Butyl is very forgiving. What I do when doing anything like what you are doing or doors and windows, I use a little excess, install the part, wait a few days and then use a putty knife to trim off the oozed out excess. There is PUTTY TAPE and there is BUTYL. Different compositions. I like Butyl. Doug

Sounds like a cool idea, of course in this case it can't be scraped off really once it's together...I could swear they didn't do a symmetrical job from the factory by the looks of it when it came apart