I guess this is the rite place to post this, if not please move to where it needs to be. Anyway my neighbor has a Case/David Brown 885 that she used last season to shred her pasture, this year she started to shred but the pto would grind and not go into gear. I went and looked at it and finally got the pto to engage, I think the pto disc was stuck. How do you adjust the main clutch and pto