Hello i am experienxing the exact same symptoms
On an older hyster with a wet clutch.i believe sump and scavage clutch? I can see oil in there not sure of level?
Wondering if you ever fixed this issue? Or ever got the clutch free..or have any advise for me before i tear it apart.i did make sure that i adjuated all the slack out of the pedal linkage.i also removed the top inspection plate..for a visual inspection. I believe i can see the throw out bearing moving when pedal moves.also has resistance.but clutch plates seem to have a welded symptom.will start in neutral and wont allow it into fwd or rev.but when off, you can start it in gear. Clutch pedal does noting. Someone please add to this thread..