[DK on the road]

I had a leak in my rear toilet coming out from the flange on the hopper (tank) held together by 12 screws. 

The toilet was overflowing and the air pressure added after each flush was causing the hopper to purge at the flange, not out the discharge.

I added bio degradable sewer tank solution to the liquid in the tank, hoping it would slowly move towards the clog and break it down. Some of the water had passed over the 4 days after I left the solution in the hopper tank, but not all of it.  I obviously had a clogged discharge line. I removed the toilet after removing all the waste with a cut off water bottle on 2 sticks and lowering them down into the lower compartment or hopper box. 

I tried to snake the line but I only had a 5' of snake.  I should have tried harder, read on...

While the toilet was removed, I took the hopper box apart to seal it off better. The Microphor schematics say it has a 2 J bolts to hold the box on the China Bowl, mine has 2 phillips head screws. After removing the 2 screws, I tried to separate the box from the bowl, but somebody either glued it or there are more fasteners that I can't see. I didn't want to break anything so I re tightened the phillips and proceeded to removed the 12 small screws that split the hopper upper and lower box.  By the way, While the hopper box is attached to the China bowl, there are 2 screws that are extremely hard to get to. I got all of them out, cleaned the flange, lubed the rubber and carefully replaced all bolts and lightly re torqued them. I was being careful not to strip them. 

I reinstalled the toilet, plumbing and air line. I flushed 3 times and water came out of the flange again, but also out of the upper box where the hopper meets the china bowl. 

Today, I will remove the toilet and find a better, longer snake to run down the drain line.

I can't tell, but this should be a straight line to the tank, shouldn't it ? 

Should the hopper box leak as a fail point at 60 psi if the drain is plugged ?  Or am I expecting too much for it to remain sealed and air pressure bleading out the top pressure relief valve (if thats what it is) ?