Rotary Cutter Overrunning Clutch

[Texasmark]

First I prefer the PTO on the tractor to stop when I turn it off and not coast down with the cutter. Second its another weak link in the PTO drive line to fail before something expensive in the tractor gets damaged if happen to hit something that should not and not rely entirely on the slip clutch should for some reason it fails to work. Which has happened, even though it looked fine it was rusted tight even though stored inside a shed.

Like I said its mostly just me, as most will think it unnecessary or useless on live or independent PTOs.

Last time I checked, an overrun clutch made for an early Ferguson 3 pt equipped tractor did not have an over torque capability...meaning that if you put too much HP to it or it hit something, it wouldn't disengage in the drive direction.

I don't understand your comments about "First I prefer the PTO on the tractor to stop when I turn it off and not coast down with the cutter."
Ind. PTO shuts down immediately. OR clutches don't as I recall using my last one some 40 years ago or so.....it keeps spinning until the kinetic energy stored in the system has dissipated. Next the slip clutch (adjusted properly and in working order) or the shear bolt coming with the cutter are the failure mechanisms to protect the driving mechanism.

Last comment is when I had early Ford/Fergies, the PTO shaft was 1 1/8". Current Cat I-II PTO shafts are 1 3/8" so your 8N Overrun Clutch wouldn't fit your current tractor without an adapter to change the input diameter!

 

[John0829]

First as was mentioned by another it takes the strain off the internal brake (if equipped) on the PTO, the tractors PTO stops while letting the drive line coast to a stop without trying to turn the tractors stub. Also as I stated I have had a slip clutch NOT SLIP when it was suppose to due to rust even though it was stored inside and looked fine (my fault for not testing it but then how many of us actually do) and the ORC was the next weakest link that failed. Ever look in one? It is a piece of spring loaded metal that catches in a very small groove, it is WAY weaker than the drive line. I am surprised they hold up as well as they do.

ORC are readily available in 1 3/8" x 1 3/8" (check any tractor shop), I never said mine was off of an 8N but when I owned an 8N and if I still did I would darn well be sure it had one on it.

Again like I stated it is my personal quirk developed from right at 60 years of using tractors, not everyone is going to understand my reasoning and that is fine

 

[Smokeydog]

Recently added a 70hp override clutch to the Kubota M59 for two reasons.
1st, needed extension for 6’ tiller pto shaft. Pat’s quick hitch made it short.
2nd, for a Brown tree cutter missing the OEM pto drive line that had a combination slip/overriding clutch. Too much kinetic energy going back to the tractor.
Don’t think I need pto braking often. Not sure how this effects tractor pto clutch life.

 

[mcfarmall]

I like to bring the tractor and driven implement speed down to idle for a few seconds then turn off the PTO. Even with a high inertia load it will minimize premature PTO brake wear.