Plumbing Questions? Ask a Plumbing Expert.
it depends on witch one
one toilet they made has the nuts inside the tank ( a big pain in the but )
and another has mettel gromets that sit in the china
for the one with the internal nuts do as follows
at the hinge pry up the covers and expose the bolt attempt to reeach in the tank and try to hold back on the nut with a small pair of water pump pliers or possibly with a basin wrench ( this is a pan in the neck so dot get discorreged ( Warning dont break the plastic flush valve they cost about 150 to 170 to replace
if you have the gromet style just turn the screw under the hinge cover if it just spins call 1-800-4 KOHLER and they will send you a free kit to install a new seat screw kit