The pto clutch has stopped disengaging on the 860. Not sure if it has stuck itself to the flywheel from little use or if the adjustments I made back whenever I split it(maybe '06?)didn't keep. Definitely not from wear. I haven't put that many hours on the tractor, practically none on the pto.
It could be rust/frozen from sitting up winters. I've been very lax keeping the clutch pedal blocked. I've always gotten away with it, especially on the 8N, because I find an excuse to get it out in pretty much any weather.