Having just completed the restoration of my used and abused 650, I felt sorry for it! (before and after pics attached). I decided it was time to run it around the block and see if anything needed tweaking. I guess I should have started with the clutch adjustment before I fired up the engine, but with the engine running and the clutch petal fully depressed the driveshaft would stop rotating, so I thought I was good. Well, long story short, I ground the gears trying to get it into reverse and now I cannot get it out of reverse. To be honest I have ground the gears before, by mistake, of course, but never had this problem.
I opened it up and found that the one shift rod is jammed and it is not going to move. I can't see that it is bent, but that is what I am thinking. No amount of force will get it to move. All the gears are free and spin when I roll the tractor back and forth, so there is no jam there. There is damage to some of the gear teeth on the outer edges. I don't know how long these teeth have been damaged, but this would maybe explain why it has always been difficult to shift. When I bought this 650 twenty years ago I initially thought that there was a problem with the synchronizers. DUH!! There are none, and I learned quickly the the tractor had to be at a full stop before changing gears. Like I said this 650 has been used and abused.
Any Ideas how to get the shift rod unstuck? Pounding doesn't work, maybe heat at a strategic point? I really don't have an immediate need for another mower at this time, so while I was having fun restoring it i always figured that it would be a "hangar queen" anyway. It would just be nice if it would roll on it's own! I'm going to try firing it up with the wheels disengaged and see what that does. Attached a couple of pics of this.