PTO engagement using a rotary mower

[hosspuller]

Interesting.

If I had to guess, I'd say that helps with the blades being balanced so you don't get as much shuddering, but I'd say that with the blades fully extended it also (slightly) increases the shock and amount of torque required to bring the blades up to speed.

Actually I would say extending the swinging blades out would DECREASE shock & toque because at initial movement, the blades will rotate backward from their inertia. For a distance of about a blade length at the blade pivot, the blade mass is acting closer to the gearbox. Only after centrifugal force overcomes friction and air resistance does the blade move to full extension.

 

[SPYDERLK]

I don't know if it helps or not but what I try to do is manually, by hand, extend the blades to their straight-out cutting position before starting up the tractor. With the mower still on its dolly this is easy and safe to do. Combined with always engaging the PTO at the lowest possible RPM, this eliminates most of the bouncing that I used to get when starting the mower.

Actually I would say extending the swinging blades out would DECREASE shock & toque because at initial movement, the blades will rotate backward from their inertia. For a distance of about a blade length at the blade pivot, the blade mass is acting closer to the gearbox. Only after centrifugal force overcomes friction and air resistance does the blade move to full extension.

Yes. ... A quarter to half turn at much reduced inertia before it starts to increase. Great idea.

 

[LD1]

My MX has a lever to engage the PTO that dont require clutching. It slams things into motion just like an electric switch would. I dont like it and dont operate that way.

Tractor still has a clutch with disengages the PTO. So I clutch, engage PTO, then slowly let out clutch, just like old school.

Stuff without alot of inertia, like the 54" tiller, or post hole digger....it does fine without clutching, but not a bushhog.

 

[arizona98tj]

Thank you for the responses. Unless I missed it, no one responded that has a Massey with the same PTO control configuration as mine. I hesitate to perform engagement in reverse order (push the button, then move lever) as the owner's manual is quite adamant not doing that. I want to think I read in a forum some time ago (before I had the rotary cutter) that gear grinding is the result of doing it in reverse. I didn't mention it but my 1529 is the hydrostatic drive model so no clutch pedal. Sure wish there was a way to soften the PTO engagement.

 

[Scut 4 Big Bucks]

I just picked up a 4' Land Pride rotary mower today, to use with my Massey GC1715. I read this thread before I bought it, and was wondering if my unit would do the same. Hooked it up this afternoon, and yes, it is quite a raquet when the rotary mower starts up. Doesn't seem right, but that's what is does. Not something you want to start and stop frequently, as I just kept the mower "on" when going from weed patch to weed patch.

 

[arizona98tj]

Not something you want to start and stop frequently, as I just kept the mower "on" when going from weed patch to weed patch.

That is bascially what I ended up doing yesterday afternoon when I took it out for a test run. I didn't like doing it that way but it seemed to be the lesser of two evils.

 

[JWR]

Hey guys, I would not stress out too much on this rotary cutter engagement noise thing. Without being there, I can't say for sure what you are experiencing is "normal" but I have never seen a bush hog that did not raise a big racket when you first turn on the pto. I've owned at least 4 and used them on 3 different varieties and sizes of tractors from a B2150 Kubota to a MF2660 to a JD4700. Never heard of one that caused a problem or damaged a tractor due to the start-up. Sure, ease it on to the extent that you have control to start the rotation, but beyond that don't worry.

 

[stuckmotor]

It sounds to me like the pto system was fine until MF improved it until it was broke.

 

[Ford850]

Adding a slip clutch to the rotary mower, if it has a shear pin now, might help reduce the shock.

 

[Gary Fowler]

Adding a slip clutch to the rotary mower, if it has a shear pin now, might help reduce the shock.

I would think that if the clutch slipped at startup, it would slip badly when mowing.
If the OP is worried about gear damage, then the best thing to do is just follow the OEM manual and throttle it down till it is just above stalling when the PTO is engaged. This might require a couple of tries to get it just right without over revving. I don't think it is going to damage either the tractor or mower even though it makes a ton of racket.