jml755
Silver Member
so the shear pin should be what attaches the pto to the gear shaft?
Your cutter is designed to have a "fuse" in the drivetrain, either a shear bolt OR a slip clutch. If you don't have a clutch (mounted at the implement end) before the gearbox, then the "fuse" is that bolt (usually 1/2") that tessiers mentioned. If you have a shear bolt make sure it is a grade 5 bolt and NOT a grade 8. You're not looking for an indestructable bolt in this application. You WANT it to shear (i.e. blow the "fuse"). I carry a half dozen extras on the tractor. I've seen a few yokes break but it's always because the drivetrain was put into a position that were beyond the mechanical limits, usually when the pto was running. Turning in too small a radius with a manure spreader will do it. Dead Horse has good advice to operate an implement through the full range of movement with the PTO running. Once you do that, make sure you record or mark the settings of the top link if you use it on multiple implements.
Hitting a log (or other obstacle) is pretty common so you've got to make sure that the shock to the system DOESN'T get transmitted to the tractor. If you blew a perfectly good yoke and you replace it without making sure something else gives first (clutch or bolt), you'll be doing it again.