well there should be 2 hinges rite behind seat. you wont see the screws cause they are under a plastic cover. take a flat head screw driver and pry up cover. lil cover should lift up towards tank. then you should see screws. the nut is under bowl you have to bend down then look up to see them or do what i do and feel for them. take big flat head or big philips screw driver and while you hold nut titen screw. hope this helps. duane:)
r u sure ur seat doesn't have a screw to tighten it from above? alot of these back to wall pans that we fit tighten from the top using a philips screw driver
This guy's video tells you how to service the parts:
For me the problem turned out to be that these gears got misaligned at some point. The blue piece should be "locked" into this position. If the white gears are not aligned correctly they will get stuck and the seal at the bottom (the flapper) will not slide freely down all the way.
