Woodmaxx 8M chipper infeed clutch adjustment

[Overtaxed]

Had my 8M for about 3 years now and I'm having a problem with it where the clutch is jumping out before the tractor really gets loaded. Took it apart today and the two plates that come together are rounded, that's why it's popping out, as the torque rises, it'll ride up and over. I found the part to replace it; but what I'm wondering, how is this thing supposed to be adjusted? I can change it from "fully engaged" (where it won't pop) to loosely engaged, but it seems that anything other than "full engagement" is going to lead to the same issue, the edges of the clutch getting worn down when it pops over.

So, how is this thing supposed to work? Is "clutch" a misnomer here, it's really an "engage/disengage" (with no slipping allowed/expected at all)? If so, I'll just adjust the new one to "full engage" and be done with it. The problem with that, a few times I have chucked something in there that really did jam it, and then it's a mad rush to the PTO switch on the tractor to stop it spinning before the belt burns up.

Any suggestions? Oh, and more confusing, there are adjustments available on engage the clutch other than fully. Nothing showing in the manual about how to adjust, just that it's adjustable.

(WM-8M) Clutch assembly includes part (WM8M-7-5,7)

 

[Wyobuckaroo]

It is obvious that arrangement is either fully engaged or not engaged.. No in-between..

If you have or need sensitivity adjustment you will need to look for that somewhere else in the drive mechanism..

Either a slip clutch on the pto... Weaker sheer bolt on the pto...

Isn't there a speed control on your infeed ?? Dull cutting blades ??

 

[Overtaxed]

It is obvious that arrangement is either fully engaged or not engaged.. No in-between..

If you have or need sensitivity adjustment you will need to look for that somewhere else in the drive mechanism..

Either a slip clutch on the pto... Weaker sheer bolt on the pto...

Isn't there a speed control on your infeed ?? Dull cutting blades ??

Sure seems "obvious" that should be engaged or disengaged. But then, you run into this little gem in the manual (troubleshooting section):

Problem: Feed roll clutch kicking in and out of gear excessively
Causes: Flywheel knives are dull.
Material jammed in chute.

So, what the heck? What I was thinking, seeing it, it's "engaged" or "disengaged" there's no "kick out" or "slip" in the way it's designed. But, there it is, black and white, saying that the feed roll clutch should be able to kick in/out of gear:

I've been looking for more details on that clutch mechanism and I just can't find it. Don't know if it's supposed to "pop" when there's too much torque (and, if so, the part that's giving me problems now it clearly a "wear" item, each pop is going to take it's toll on that thing) or if it's only there to stop the infeed if you need to (which it does do, of course, if you pull back on the control bar and separate the two pieces.

It's possible to adjust it, at least I think it is, so that it'll never kick out, it's on or off. If you put a branch in gets jammed, the belt smokes and you run for the PTO shutoff! That's how mine used to be before I adjusted it, it's really nice now because I don't need to worry, if it overloads, the clutch stops feeding. However, now it's stopping the feed too much because of all the wear to the mechanism.

Just not sure what to think, it would be great if there was a setup guide for the "clutch" describing how it's supposed to work and how you should set the stops.

No speed control on infeed on this model, 50ft per min. There is a shear bolt on the PTO shaft already, but that worm gear is like a 100-1 reduction, and it's driven with a belt, no way you'll ever pop a shear bolt before you smoke the tiny belt that drives the worm gear.

Manual:
WoodMaxx-WM-8M-Wood-Chipper-Manual.pdf - Google Drive

Here's a picture of it up close:
http://i1175.photobucket.com/albums...axx WM-8M Mechanical Gear Box_zpshs12iumv.jpg

 

[Overtaxed]

Well, my new clutch came in from Woodmaxx today, still trying to figure out how to set it correctly though. When it came, it was set with "no give", if you put in a branch that got stuck, the belt would smoke on the drive motor. Perhaps that's the best option, belts are cheaper than clutches and you have a few seconds to stop the drive before the belt lets go. Still I would love to know the theory of operation here, how is this thing supposed to work and kick in/out of gear?

 

[Wyobuckaroo]

But, there it is, black and white, saying .......

+++
Not all instruction manuals, set up instructions are written correctly.. Or the set up steps correctly sequenced 1 through the end..

I have written a lot of set up and procedure manuals for making parts in the tool and die shops.. The best advise I ever got about how to do that was to think of it as if you were describing how to defuse a bomb...

Meaning, don't say something like .... cut the red wire, only after you have cut the blue wire...

I'm thinking there is missing info, or info out of sequence.. It may be a good place to start from the beginning.. At the pto shaft it drives the pump, the pump goes to a valve, is there an adjustment on the valve ? and on from there is the drive motor....

 

[Overtaxed]

But, there it is, black and white, saying .......

+++
Not all instruction manuals, set up instructions are written correctly.. Or the set up steps correctly sequenced 1 through the end..

I have written a lot of set up and procedure manuals for making parts in the tool and die shops.. The best advise I ever got about how to do that was to think of it as if you were describing how to defuse a bomb...

Meaning, don't say something like .... cut the red wire, only after you have cut the blue wire...

I'm thinking there is missing info, or info out of sequence.. It may be a good place to start from the beginning.. At the pto shaft it drives the pump, the pump goes to a valve, is there an adjustment on the valve ? and on from there is the drive motor....

Kind of what I'm trying to do, reverse engineer how this thing could possibly work coupled with the instruction manual. On my chipper, it's not a hydro feed, it's mechanical. There's a takeoff from the PTO shaft to a pulley, that pulley drives a reduction gear that greatly brings down the speed, that reduction gear goes into a "clutch" and the clutch goes to the feed roller. It's entirely obvious how the "clutch" stops the feeding of material, it's like a gear with 2 teeth on it, pull the "stop" lever, you pull those teeth apart and the drive is stopped. So, that part makes sense (and works as expected).

However, the theory of operation that I do not understand is when they talk about that clutch "popping out" in manual when the material gets jammed. Mechanically, that would be like your truck popping out of gear if you put too much force to the ground; yes, that can happen, but NO, that's not an expected mode of operation and, if you do that much, you're going to wind up with rounded over gears that don't hold anymore. Which is exactly what happened to my chipper, it would "pop out of gear", but, looking at the mechanism, it's obvious you have some very limited amount of times that will happen before you round over the teeth and it won't hold itself in gear anymore.

I've put in the new "clutch" and I've set it for full engagement. It won't pop out anymore no matter what, if you jam something in there, it'll smoke the belt. I think that's the right way to set it up, but I'd really like to KNOW. I did send Woodmaxx an e-mail a few weeks back asking, never heard anything. Maybe I'll give them a call this week and see if there's someone who can explain how it's supposed to work.

 

[oldballs]

For issues that I have had with various equipment (in the past), I've found that customer support usually gave me the right answer. Maybe your phone call will get you the right answer.
cheers,
Mike

 

[jonsstihl]

that seems like a poorly designed system. I don't want to crap on the wood max but my woodland mills is designed differently. it is a hydraulic feed roller so there is a relief valve. I have jammed the roller enough that I may look into adjusting the pressure of the relief valve.

I think your best option is to jam the clutch to the on position and keep a few spare belts on hand depending on what costs more the belts or the clutch parts.

you shouldn't have to run to the pto switch on the tractor. you just need to grab the control bar and pop it into neutral but can you reverse the direction on the roller with the mechanical setup?

 

[Overtaxed]

that seems like a poorly designed system. I don't want to crap on the wood max but my woodland mills is designed differently. it is a hydraulic feed roller so there is a relief valve. I have jammed the roller enough that I may look into adjusting the pressure of the relief valve.

I think your best option is to jam the clutch to the on position and keep a few spare belts on hand depending on what costs more the belts or the clutch parts.

you shouldn't have to run to the pto switch on the tractor. you just need to grab the control bar and pop it into neutral but can you reverse the direction on the roller with the mechanical setup?

Belts.. And they are easier to change, so I think that's probably the best option. Thing that sucks, I'll have to be careful when feeding it, can't just chuck and walk away in case it sticks. And you're right, the control bar will disengage the roller, but that still means I need to stand there babysitting it.

I'm not sure why they don't use a real "clutch" in the system. It's not crazy high HP because it's reduced so much, you could just use something like a simple PTO plate clutch and you'd never burn that up at the very low RPMs of that shaft.

Woodmaxx does offer a chipper with hydro feed, I just wanted to save some money (I'm cheap). It does sound like that's a big advantage to hydro though, especially if you're chipping gnarly stuff that will jam at times because you won't burn anything up if the hydro stops turning.

 

[jonsstihl]

I jammed the first piece of wood I sent through my woodland mills WC68. had a decent crotch in it but I thought it could handle it. Turns out mine had a defect and the 6 inch chipper was actually only a 4" chipper. interference between the swing arm for the roller and the bracket that held the valve didn't let the roller rise higher than 4 inches. had to cut off part of the bracket and reweld an extension to remount the valve higher up.

Woodland mills customer service was excellent and they presented me with several options as soon as they were made aware of the problem. I chose to modify since I had already assembled and filled it with oil and didn't really feel like sending it back.

Maybe you could find a slip clutch for a smaller pto shaft and modify yours.