PTO stops quickly with Rotary Cutter

kilobravo3 · Sep 12, 2006

Hi gang,

I have a JD 855, but I believe it is made by Yanmar, so I thought I would post this here. I just got my King Kutter rotary kutter and was cutting the back yard yesterday. I noticed when I turn off the PTO, the pto stops spinning very quickly. I'm not sure if this is normal or not. Most of my tractor experience is on larger New Holland tractors and the bush hog will spin down for about 1 minute after disengaging the PTO. Also, with the New Hollands I can turn the blades of the hog while it is connected to the tractor....this is not the case with my John Deere. I can't turn the blades at all on my 855 while it is connected (well, maybe just a 1/8-1/4 turn). I just want to make sure I don't damage my tractor. Does this sound normal?

Thanks.

Tractors4u · Sep 13, 2006

The 855 has a Yanmar engine but the tractor itself was built by Deere. I believe the reason you were accustomed to bush hogs that would free spin is because some tractors have a built in over-run coupler that would allow the bush hog to free spin for a while. The PTO of the 855 is independent and the fact that the 855 had a hydrostatic transmission might have something to do with how the PTO acted. I had an 855 but I never used a bush hog with it.

kilobravo3 said:
Hi gang,

I have a JD 855, but I believe it is made by Yanmar, so I thought I would post this here. I just got my King Kutter rotary kutter and was cutting the back yard yesterday. I noticed when I turn off the PTO, the pto stops spinning very quickly. I'm not sure if this is normal or not. Most of my tractor experience is on larger New Holland tractors and the bush hog will spin down for about 1 minute after disengaging the PTO. Also, with the New Hollands I can turn the blades of the hog while it is connected to the tractor....this is not the case with my John Deere. I can't turn the blades at all on my 855 while it is connected (well, maybe just a 1/8-1/4 turn). I just want to make sure I don't damage my tractor. Does this sound normal?

Thanks.

kilobravo3 · Sep 13, 2006

Thanks for the response. Do you think an overrunning clutch would be of any use in this situation?

Normmm · Sep 13, 2006

A hudrostatic drive machine uses hydraulic motors to power its moving parts. It may be that the cutter is slowed by the drag of an unpowered hydraulic motor. Which is really just a pump. Contact a JD dealer and ask If this is normal. I would think it is and the slowing of the cutter sounds like a good thing.

buppy69 · Sep 13, 2006

The PTO on my Hinomoto N239 comes to a quick halt also. I think it's a nice feature.

Eugene

Soundguy · Sep 13, 2006

Normmm said:
A hudrostatic drive machine uses hydraulic motors to power its moving parts. It may be that the cutter is slowed by the drag of an unpowered hydraulic motor. Which is really just a pump. Contact a JD dealer and ask If this is normal. I would think it is and the slowing of the cutter sounds like a good thing.

Just to clarify... the pto on a hydrostatic trannied' tractor is not fully hydraulic*... It is most likely still countershaft driven.. and independent via hyd controlle dclutches.

Also.. it likely has a pto break... no big deal.. lots of tractors do.. just make sure you idle down real low before disengaging the pto, so as to save wear on the pto brake.

*(I know of at least one tractor-ish machine.. a powertrac.. which has a fully hyd pto.. that is.. it is a pump/motor setup.. not a shaft that is coupled to the engine.. etc.. )

Soundguy

kilobravo3 · Sep 13, 2006

Thanks again gang. I really appreciate the input. I read my manual and it did mention a PTO brake. I just thought it seemed like an awfully violent stop even at idol. But, I'm guessing that stems from me working on tractors that don't behave that way, so the way mine works isn't wrong....just different.