Small Engines (Lawn Mowers, etc.): Tire stuck on axle, emery cloth, air hammer

Question
I have a 18.5HP 42" deck lawn tractor that rear tire is stuck on the axle. I have used emery cloth on the end and a home-made gear puller and only moved about 1/2" to the end but will not budge another inch. Was very rusted and cannot repair tire. Any suggestions to get the rim loose and off the axle? Tire size 23"x8.5"x12" tractor was left in weather for a while and given to me, runs great except back tire is stuck

Answer
Is the tire too bad to use some of that Slime sealer?

Have you used a good penatrating oil such as PB Blaster or Kryoil?

A torch may help but don't ruin the axle seal.
You may want to tilt the tire/rim up to help the penatrating oil flow into the rim hole.  Soaking for several days may also help.

Do you access to an air hammer?
Let me know.
Eric