Rotary Cutter Bush Hog Troubleshooting - Woods? Slip Clutch Issues with Kubota M60

[5030]

Looks like a Weasler slip clutch to me and Weasler sells new plates for it. Needs to be slipped (to remove the rust buildup) every year prior to first use.

 

[RayIN]

Use the correct size shear bolt, slop increases the shear effect. The gearbox shaft is hardened. Tighten the nut to its maximum torque value, no lock washers. If the nut works loose, a drop of LocTite is needed after removing all oil N grease, or 2nd nut.

 

[sandman2234]

Make sure there are no sharp edges on the sides of the hole where pin goes thru. I had a pin shear, and got smeared around the inside of the outer piece, which caused an edge. I kept shearing pins till I took a dremil tool to it.
David from jax

 

[BackRoad]

Good stuff above, the only thing I might add is your tractor could easily turn an 8' rotary cutter, so it's possible you are over powering the 6' mower...but by all means, go with what you have!

As others have mentioned, break your slip clutch free. *IF* that is set correctly and working as designed, the grade 2 sheer bolt is redundant and the weakest link. Sounds like it is breaking before the slip clutch gets a chance to...slip.

As Mr. Lineman mentioned, you can safely increase the bolt grade (hardness) and rely on the slip clutch...if you have it dialed in.

You might need to go easy with the mower, meaning low RPMs when you engage the PTO, then increase to 540 RPMs, and limit the size of saplings and brush you attack until you've confirmed the slip clutch operation.

Cutting brier canes should not be a problem...

 

[gstrom99]

You might need to go easy with the mower, meaning low RPMs when you engage the PTO, then increase to 540 RPMs, and limit the size of saplings and brush you attack until you've confirmed the slip clutch operation.

Cutting brier canes should not be a problem...

I NEVER engage the PTO on anything, at more than 1/3 throttle.

 

[BackRoad]

I NEVER engage the PTO on anything, at more than 1/3 throttle.

For my implements, engaging the PTO at idle seems to be the least stressful method.

I have an old 5' brush hog of unknown manufacture which functions well behind my 60 yr old MF TO35 which bragged of 32hp at the PTO when new. Cutting fields is easy, and brush or saplings upto about 2 inches are no problem...never broke a shear bolt.

That same 5' rotary mower behind my 60hp Kubota MX6000 goes through shear bolts pretty regular on PTO startup if I don't baby the PTO. The torque hit at anything above idle twists them in two. Once up to RPMs, it cuts field grass without issue.

And behind the MX, powering through brush of 1 to 2 inches can result in broken shear bolts. That's why I bought a much beefier 7' Woods!