Thanks for the head up. To be honest, I have not taken apart the several SS114 seats that need to be repaired. When I get around to it, will put up pics. From my limited research I have here, it seems the older seats were made in USA for TOTO by Centoco, so it's possible the mechanism are also made by the same company?
I just fixed a soft-close SS114 (or very similar model) seat yesterday, but I forgot to take pictures. It was pretty old it seems, maybe at least 20-30 years. The mechanism and procedure
described in post #4 is accurate, as far as it goes. The mechanism seems to be identical to that in a new SS114 I just bought last week.
It's really quite simple, but it involves bending little prongs/tabs of plastic and doing so without breaking them is quite challenging, as was the whole
trick of pulling out the metal hinge shafts from the left and right hinges. The tool I succeeded with there was a long curved locking hemostat.
Then removing the damper assemblies requires bending another little
plastic lock tab. The assemblies are identical, but will only fit back in the seat one way. For some reason, I found I had to have the hinge/seat/cover in
the full-open position to get things back together. Only one of the damper assemblies was defective, and it was obvious it was missing most of the
original damping fluid. I used a little tube of Permatex Dielectric Tune-up Grease (available at most auto parts stores, I would imagine) to top up the
two fluid chambers in the assembly. It's a silicone grease a little bit thicker than what I found already in the damper channels.
The repaired seat has been working fine so far. FYI, the 2 little clear soft plastic pads that go between the seat and the bowl will discolor and
absorb un-removable "toilet odors" over time. I would recommend replacing those if possible. I've only seen them available as part of
a Toto toilet installation kit.