Hinge#85057 broke, cannot remove screws they are inside toilet,as i cannot cut they off i don't know how to loosen them.

I'm sorry to hear about the issue you're experiencing with your Coroma Opal II toilet seat. If you're unable to loosen the bolts that secure the seat to the toilet bowl, here are a few suggestions you can try:
1. Apply penetrating oil: Spray some penetrating oil, such as WD-40, onto the bolts and let it sit for a few minutes. This can help loosen the rust and corrosion and make it easier to remove the bolts.
2. Use a wrench or pliers: If the bolts are not budging, you can try using an adjustable wrench or pliers to grip the bolts and apply more torque while attempting to unscrew them. Make sure to hold the nut underneath the toilet bowl to prevent it from turning.
3. Apply heat: Heat can sometimes help break the bond caused by corrosion. You can use a hairdryer or a heat gun to warm up the bolts, which might make it easier to remove them. Be cautious not to overheat any plastic parts.
4. Cut the bolts: As a last resort, you may need to cut the bolts using a hacksaw or a reciprocating saw. Take care not to damage the toilet bowl while doing this.
If you're still having trouble, it might be best to contact a professional plumber for assistance. They have the tools and expertise to handle difficult situations like this without causing damage to your toilet.

Put towel on floor, look underneath unit with a flashlight - look for a hole below the seat hinge area - screw inside turn screw (leftie- looses) Could be slot, Phillips head or other, like a hex head. Whatever - loosen both sides and check for slack by pulling up on seat, then remove screws down and seat up- done

You will have to remove the pan to access seat fitment as sounds like a back to wall lol.
Alternatively cut through bolts holding on seat with a hacksaw blade and go to plumb center and buy a new seat with drop through fasteners

Wrap a putty knife with a wash cloth, and push it between the toilet ceramic surface and the plastic hinge for the seat. Wedge it in there. Now try unscrewing the hinge screw. This provides back pressure against the hidden nut on the other side and may let you successfully remove the screw.

Not very difficult if like my '99. Be sure to purchase the correct hinge for "power" door. Here are the steps:

• Remove rear tail light (2 screws and pull from socket)
• Remove two screws from rear of hinge cover panel
• Remove bolt from front of hinge cover panel
• Open door around one foot and rest the back end on something about the same height
• Remove the three bolts from the hinge connecting it to the door
• Loosen slack on cable by unbolting pulley under inside rear panel (tire tool storage on driver side)
• Slide broken hinge out back of rail
• Replace new hinge and put all back together

I don't know if there is a simpler way to loosen the slack on the cable, but this is how I did mine.
Hope this helps.

I have a Toto Dorian 1.6 Gpf where the right side of the cover separated from the seat frame. I fixed it by removing the seat from the toilet base and driving the stainless steel shaft back into the cover hibge holes.

To remove the toilet seat, use a large phillips head screw drive and unscrew the two long screws that hole the seat to the base.

Then you will see the two steel rods about 1/4 inch in diameter that have worked there way out of the seat hinge. Use a hammer and a screw driver to drive these two hinge pins back out into the toilet seat cover hinge holes.

Replace the toilet seat and screw in the two seat screws being careful to not over tighten them. The seat should now work correctly.

two screws at back of seat is two square caps lift caps there is either two philips screws or two flat head screws when you grab screw driver get a pair of pliars to hold nuts on bottom of the screws hold the nuts as you are loosening the screws then just go to the home depot or supply store you like get toilet seat that is egg shaped buy and put in old ones place

Most generic seats have a thin plastic cap that snaps in place over the bolt heads just behind the seat. Normally they hinge backwards so carefully pop them open with a flat blade screwdriver. Sometimes you can tighten the bolts from underneath even.