I have a mid 80s 1910 4wd with 1180 hours. It runs like a champ and is impressive for the size and weight. After a couple of months of moving soil, I hooked up my finish mower and discovered that the secondary clutch would not engage the pto. Your posts on this topic have been useful, thank you. What I discovered is that the secondary clutch linkage is not engaging. The primary clutch is working fine, but the link that pushes the second clutch open (rear axle) doesn't move with the foot pedal. I can't figure out what attaches the second lnkage to the first linkage and my manual doesn't address. Can someone share if the second clutch moves through a key of some sort or otherwise connects to the first clutch pedal roller with a weld or pin? At first glance it was a relief that just the linkage was not working, but after a cuople of hours of inspection.....i can't figure out how the two work together off the clutch pedal. Any help is appreciated.