Wolfman, I understand what you mean by bypassing the system for the 3 pt!This is even more enlightening / concerning as yes all four systems (FEL, HST, Steering, Three point) use the same hydraulic loop to make them work.
Any issue with one in line can effect everything else.
How did you bypass / go around the broken three point control?
The hyd system on the tractor is not what I would call a closed system. As in if you open one of the four you would need to bypass it. The other 3, Steering, bucket, and travel all function fine without the Hyd Control Valve functioning for the 3pt operation.
So, that being said, what would you check/trubble shoot next if the PTO is turning fine even if the tractor won't move or bucket operation.