Water is leaking from someplace, but where?
Take it a step at a time.
1) Wrap a paper towel around the point where the flush hose attaches to the back of the toilet bowl. Give it a few cycles, then check for moisture. Be sure you include the hose connections, as a loose connection there would absolutely do what you describe.
2) Repeat, wrapping the paper towel around the flush valve at the base of the treadle, where the hoses connect to the valve as well as below the valve.
3) Open the trim cover at the base of the bowl and remove it. Make a “snake” about 24” long out of paper towels and wrap around the TOP of the split ring and band clamp assembly. Test there.
4) Repeat 3, at the BOTTOM of the split ring and band clamp assembly.
That covers all the possibilities for any kind of a connection leak with any possible pressure. So, let’s check the hoses.
1) Wrap a paper towel around the low point on each of the hoses connecting to the toilet - the PEX in feed, the line out to the vacuum breaker at the back of the bowl, and the line to the hand spray unit.
2) Wrap a paper towel around the treadle axle penetration of the black pedestal base.
3) Wrap a paper towel around the base of the pedestal where it is bolted down to the seal.
That covers the toilet system. Next, pull the angled pieces of paneling at the back of the toilet (Phillips head screws) and remove them. There are a number of hoses and connections back there. Check them all the same way. It could be leaking there and seeping out to behind the toilet.
The shelving under the toilet counter top sits on top of linoleum. A leak between the bathroom stuff and in my midbath, the under counter kitchen area could have a leak that is traveling to the area behind the toilet. So, use a snake of toweling and devise some way to hold it pressed against the floor next to that cabinet.
You can shorten the time for testing by doing a bunch of these at the same time. Just don’t let one interfere with another setup. When wrapping a paper towel around something, scotch tape or quick ties are your friends for keeping it in place.
When you are done, your toilet is likely to resemble a volunteer victim at a Brownie first aid class… ;-)
Hmm, water escaping where the toilet base meets the floor…
There is a hard plastic mount on the floor that connects to the sewer pipe. That mount might be cracked. Between that mount and the base there is a relatively soft floor flange. It that became torn somehow, that could leak. However, there is nothing but air behind those pieces, so I don’t see water escaping there. The base itself has a number of sections intended to stiffen the base without adding much weight. A leaking upper seal can allow standing water in the bowl to leak out to those sections. Andy and I have both seen those spaced filled with water. I can see that area overflowing, leaking down the side of the base onto the floor. I can also see a base with a hole or a crack allowing those spaces to leak onto the floor.
About a month ago, I replaced the two upper seals. Two days ago, the spring cartridge broke, necessitating replacement. Dreading the possibility of dropping the flush ball into the black tank, I decided to remove the base to do the repair. I pulled out the toilet and set it in the shower. While there were some salt deposits on the bottom, they cleaned off easily with a brush, not yet having hardened. I looked at the seals, which seemed to be in good shape. They were only a month old and looked fine so I cleaned them and set them aside to re-use them. Big mistake...
I then removed the water valve, unbolted the base, and put it in a bucket of HOT soapy water to soak a bit before cleaning. While that was happening, I cleaned up the mounting flange in the floor, blessing LD for using caulk on the mounting bolts and under the floor flange.
Shortening this tale, I cleaned up the base, removed the rotor shaft and flush ball, prepped and installed the new shaft and rotor ball, re-assembled the flush pedal, the spring cartridge and the water valve, then I waxed the surface of the new flush ball and put the seals from a month ago back on. I installed the toilet, inserted the vacuum breaker, put on the split ring clamps and tightened the band clamp.
I then used the flush pedal, adding water to the bowl. All looked fine and I was congratulating myself, until I noticed that the water was flowing out of the bowl. The old seals, that I re-used, were leaking, and the water was emerging from the seam between the toilet bowl and the plastic base.
AND - I was experiencing some abdominal cramping. I did not have a lot of time to deal with this.
Feeling some urgency, I pulled out the vacuum breaker, loosened the band clamp, removed the split rings, moved the toilet to the shower, and found that the interface between the toilet base and the upper seal had not sealed. Water had flowed across the top of the seal, filled the flanges in the base and overflowed to the floor area around the base.
I did some quick mopping up, grabbed a new set of seals, installed them, installed the toilet and vacuum breaker, put on the split rings and band clamp, and snugged it all down. I added some water, and it held.
I had once claimed that, but for cleaning, I could probably change the seals in 20 minutes. It actually took me 15 minutes, and, had it taken 20, that would have been 2 minutes too late.
So, here is what i think. You re-used your upper seals, right? I have learned that that does not work. They may look good, but unless they will lie perfectly flat on a flat surface, they are likely to leak. Second, when you changed the seals, did you remove all encrustation and salt formations from the underside of the toilet bowl? If not, that irregularity can cause a leak.
From your pics, I think you have everything lined up properly. I suspect that when you flush the toilet, the old seals are allowing water to escape to the flanged area in the base, thence out through the seam between the base and the bowl. With the flush pedal released, the flush ball pushes up against the seals and they make enough contact to stop that flow, so the water stays in the bowl.
My recommendation is to remove the toilet again, make sure the bottom of the toilet is free of any deposits or encrustation ( I have had to use a file at times to remove them), then re-assemble with new seals.