3-Point Hitch Starting up and running a PTO Chipper on the B2650

[Porchfan]

So I picked up a used Mackissic PTO chipper on CL from a local farmer and ran it last week a few times. The chipper knives were pretty dull and it was a struggle to chip anything larger than about 2 inches. I orderd new knives and it ran much better after I installed them per the install instructions. I chipped a 4 in sapling I had cut and it sucked it up pretty well. Check it out. I have a few questions though:

I was wondering what's the best way to engage the PTO for a chipper - at medium RPMs? I noticed the whole chipper moved due to the torque on the PTO when I engaged it when it was set to 540.
Maybe I should start at a lower rpm and then increase it as it spins up?

When it ran on my tractor under heavy load ( 4in limb) it slowed the 540 RPMs a bit. The PTO HP is 19.5 on the B2650.
Should I set the RPMs a bit high on the rear PTO before chipping these larger limbs?

Thanks,
porch

 

[CalG]

I always get the machine spinning with the engine at idle, then bring up the revs to normal working speed. Same on the way down, First the throttle gets chopped, then the pto clutch is disengaged. It probably doesn't make a significant difference, but just seems right.

I often run the chipper shredder with the 1000 rpm pto, and pull the engine rpms back to keep from over speeding the shredder. That works well for lighter stuff, like leaves
If I'm only "chipping", then the 540 rpm pto is used.

I've found most of the load on engine horsepower is experienced when allowing heavy self feeding into the chipper (Sharp knives can really be aggressive in this respect). Also when the material clogs on the shredder screen and just churns instead of being ejected. I have no need for any "fine" screens, as I would rather send material through a second time than to deal with clearing screens. One tip when shredding is to have on hand a supply of small limbs to send through the chipper to act a "scrubbers" and so clear the screen.

The use of the chipper shredder has significantly changed the way garden compost is generated. All in ways that seem to be good!

 

[Porchfan]

Thx. Yeah I definitely need to lower the RPMs on startup. And you're right, the chipper is aggressive with those sharp knives. I have not really used he shredder much. Most small leafy twigs. It seems to just rip the stuff to pieces. I guess leaves in the fall can be thrown down the Shute. The farmer I bought it from told me to add the twigs leaf side first. He also lifted up the lid. When he ran it before I bought it, it pulled those twigs into the shredder violently. The RPMs were high then. Maybe they should be much lower like you said to 1000 RPMs or so. Anyway. Thanks for the advice. The chips and mulch it generated will be tilled into our new garden in the fall.

 

[s219]

Definitely don't engage at PTO rpm! I normally engage at a little above idle, and then slowly throttle up to PTO rpm.

To stop the chipper, I normally push in the clutch and hold it in while the chipper spins down until the PTO shaft stops turning. While waiting, I throttle the engine back to idle. However, the B2650 doesn't have a clutch like previous models, so I am not sure what to recommend -- maybe look in the owners manual.

The danger in dropping the throttle with a rotating implement attached is that any heavy rotational mass (i.e., flywheel) in the implement can put a back-load on the PTO system, driveline, and engine. If there isn't a clutch, I suspect the best thing would be to throttle down very slowly.

That's not a major concern with your particular chipper, as I believe it doesn't have a huge flywheel. But some brands -- like Wallenstein -- do, and you need to be real careful.

I wouldn't go higher on RPM unless the chipper owner's manual (or someone at Mackissic) says it's OK for the chipper to run at higher RPM. I wouldn't worry if the tractor engine loads up a little bit -- that is pretty normal when running a chipper. If it really bogs and wants to die, then you clearly don't have enough power. But a little loading is just fine.

 

[Porchfan]

There is a PTO clutch. In the manual it says to engage it slowly at half of full speed engine rpm. This is sort of what I do. Then bring it up to speed. There is also an rpm selection switch on the dash where you can see the actual rpm of the rear or mid PTOs. Here are the two pages in the manual that discuss PTO operation. The manual states the PTO will disengage when you stand up from the seat. For stationary use such as using a chipper, you do need to engage the parking brake or the PTO will go off. I had that happen a couple times when I was on flat ground and didn't realize the parking brake was not engaged

 

[s219]

Sorry, I was referring to a main clutch, with foot pedal, which would completely de-couple the PTO (and transmission) from the engine. The older B models with live PTO had both the main foot clutch, and the PTO engagement lever. So you could depress the main clutch with foot and let implement RPMs come back down at their own pace while independently throttling the engine back to idle. In that system (live PTO), the PTO engagement lever (which is in the same place as your PTO clutch lever) was a mechanical (gear) engagement.

So with an independent PTO and separate PTO clutch on the new '50 models, I suppose you could do the same thing, sort of -- just pop the lever to disengage the PTO, and that should let the implement spin down at its own pace while you independently throttle the engine back. For the reasons stated above, I wouldn't drop the throttle from full speed with the implement spinning without first disengaging the clutch, but it would be good to see if the owner's manual has guidance on that (didn't see it in the photos).

 

[Porchfan]

Correct. As soon as you disengage the PTO clutch, the implement starts to spin down. I'm going to chip some more stuff today. I'll post a you tube video of how the clutch operates and how to spiun up and spin down the implement.

 

[Jay4200]

I always get the machine spinning with the engine at idle, then bring up the revs to normal working speed. Same on the way down, First the throttle gets chopped, then the pto clutch is disengaged. It probably doesn't make a significant difference, but just seems right.

I do the same to engage all of my implements - snowblower, mower deck, etc. I don't throttle down before disengaging however - no reason to do that.

 

[TerryR]

I do the same to engage all of my implements - snowblower, mower deck, etc. I don't throttle down before disengaging however - no reason to do that.

I throttle down to an idle with any implement with a heavy flywheel, like a rotary cutter or chipper, so the moving parts stop moving sooner and thus avoid me or anything else getting entangled with them.

Terry