Classic Winnebagos & Vintage RVs

Hi there I have been looking at putting a new toilet and fixing up some things around the black water tank in my Winnebago brave. It seems like the waste tank is bolted directly to the floor of the vehicle? Does this black water tank have a top or does it utilize the floor of the vehicle as the top floor f the tank? We want to put a new toilet flange in and I'm trying to get more details before going in. Thank you

The tank is a tank mounted against the bottom of the floor. The toilet flange should be threaded into the top of the tank. The top of the flange should be fastened to the floor.

That's what I figured..thanks. I went and removed the flange as we are putting in a new toilet and the new unit only has two posts vs. the 4 that were used for the Thetford. The flange just cracked and pulled up as if it was cemented. Definitely not screwed in and there doesn't seem to be much of a seal or anything I can tell that goes into the black water tank. I'll try to get a photo for you tomorrow. thanks much.

The 2 common systems are.

1. ABS tank with female fitting glued to the tank, then the male floor flange is threaded into the female fitting.
2. Plastic tank with female fitting plastic welded to the tank, then the male floor flange is threaded in the female fitting.
The female fitting may have pulled free of the tank. That can be a problem and the tank may need to be removed for repair.