Clutch Slip Confirmation

[JCoastie]

I have an old rotary mower, I haven't used it in a while, and I have owned it 10 years, I am not the original owner, I do not know the age of the mower.
In the 10 years I've owned it, it has lived outside in the rain and sun, and I had never slipped the clutch for maintenance. Visually it appears seized.
I figured Id try to slip it today, so I loosened all the springs and after a couple bumps of the PTO switch, the clutch spun without spinning the blades. Initially the blades did spin, but after I increased the RPM to PTO speed and engaged the PTO, the shock broke it free.

I tightened the springs back to the previous measured position, and everything worked as expected.

I did not mark the clutch plates, so I have no visual representation that the plates slipped. Is it a safe assumption, that if the clutch spun when the PTO was engaged and the mower blades did not, that the clutch plates were in fact slipping?

 

[npalen]

I think that would be a safe assumption but might suggest looking at the owners manual online for some other brands of rotary cutters.
See what they recommend as a procedure for adjusting the clutch springs.

 

[Vigo327]

Is it a safe assumption, that if the clutch spun when the PTO was engaged and the mower blades did not, that the clutch plates were in fact slipping?

Yes, 100%.

 

[Grouse09]

Agree with the two guys above me. If you spun it and the blades didn’t turn, you broke it loose and “ran it in”. As long as you got the nuts tight again, you are good to go.

 

[5030]

All the above... It is advisable to spin the clutch until you get a little smoke off the plates. That way you know the plates are burnished properly. it's there to protect your driveline, all my driven implements have one.

 

[JCoastie]

thanks all, I did let it run a good 30 seconds, and I did it a couple times, I did not see any smoke, I had the spring/nuts completely loose, there was not pressure on the springs at all at that point. Maybe I'll do it again with a little pressure on the springs/plates.

 

[npalen]

The trick is to apply just enough spring pressure that it will slip if it has to in order to protect the drive line but not slip in normal conditions. That sometimes requires a little bit of trial and error and readjustment of the spring bolts.

 

[5030]

The trick is to apply just enough spring pressure that it will slip if it has to in order to protect the drive line but not slip in normal conditions. That sometimes requires a little bit of trial and error and readjustment of the spring bolts.

Exactly, and the recommended clamping pressure specified is just a starting point. I set mine so they break a tad every time I start an implement. I want to hear them give a quick 'squeal' as the driveline comes up to speed.

Mine get slipped every spring but I keep everything inside, nothing out in the elements.