Chipper engine choice: Gas or Diesel?

BeerGeek

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So, in my quest to get back in the game, my local Morbark dealer is offering me 2 engine options on the 1415/M12R: a 74HP Perkins 854 diesel or a 145HP 4.3L GM gas. All my experience w/chippers has been with gas models, but in learning more about diesels, am I correct to think I'll get the same if not more from a torque perspective, meaning better power to eat through thick limbs/smaller logs? Also, probably better fuel economy on the diesel? Also, looking at the ChipSafe option, as insurance out here is a killer (and that will save me about $1000/yr according to my agent, paying for itself in just about 4 yrs.). Anything else to consider from Morbark users? All advice/comments welcome. Thanx in advance.

- Brian
 
The fact that they use half the horsepower in the diesel to do the same work should pretty much sum that up... I'm not the go to guy with the chipper specific part if the question, but i would bet the diesel will be cheaper to run, and will have a higher resale value. Perkins are very good engines too. Another awesome thing with diesels is if you don't run it for awhile you don't have to worry about fuel issues as much as gas (like if you only do it part time and don't do much in the winter). As i get older and become more knowledgeable about engines, the more and more i like diesels. Your insurance is going to be needed for sure, but you might be able to get a discount for safety stuff like that, idk. Talk to your insurance guy for sure.
 
The new diesels have A LOT of emission devices on them now making them very complicated to work on. I have diesels but I know several guys are going gas because of it. Just something else to chew on.
 
All chippers do the same work, they chip stuff.

Those two engines are not the same. You will have to look at specs.

What kind of wood will you feed it.


A lot of guys seem to be having good luck with the 4.3L.
Feel like I heard something about using OEM parts for part of the ignition system on them.

I hear the gas engines recover faster than the diesels.

Likewise, lots of people are avoiding Tier 4, IIRC, diesels with the emissions stuff.

What has the dealer been selling and seeing with the two engine models?





What about a winch? You mentioned insurance being a killer. A winch can replace a guy on some jobs. All guys on some jobs, save the operator.
 
My small Morbark is Diesel ... Have rented and run many before buying. Diesel is more powerful fuel to start with plus more economical use of said fuel. Best Gas engines on Chippers are generally much more thirsty. Just my opinion.
 
A friend of mine is the head mechanic/overseer for a large fleet of ambulances. They are slowly getting out of the diesel engine game...changing to gas. He says the diesels run great but when they tear up are very expensive to fix. Their economic study says to switch to gas.

I have known this guy since he was a kid...probably 25-30 years now. Smart, got it together young guy, a peer of my son. He's a great mechanic (used to run a race car in his late teens and early 20's...it was an everyday to R&R his engine, tear it down, tinker between weekend races.)

My 2 cents worth.
 
In Europe a lot of manufacturers are giving petrol options on their chippers these days, wary of emissions legislation changes.

Fuel consumption is more of an issue as it is more expensive here.

On a bigger chipper that would only be used in bursts, say being fed by a loader, I’d be leaning towards petrol.
 
Gary, I've heard that too, and the main reasons were dramatically cheaper upfront, and since they usually just auction them off after they are depreciated they don't get their money back compared to the cost of the diesel in the first place. The newer diesels with the emissions stuff really start getting screwed up if you idle them all the time, whereas a gas won't really care (ambulances are idled for most of their life, as are certain construction vehicles). Gas is cheaper per gallon anymore, so the fuel economy is a wash. I considered getting a gas truck for these reasons as well, but after talking to guys who actually use them, the diesels are still a better product if you plan on keeping it and taking care of it. This truck has so much power it's unbelievable, and since i don't idle it very much it will last forever. Once it's out of warranty I'll do an emissions delete, and that will help even more with longevity. A buddy has the same truck as i do but deleted it when he bought it, it's got 150k miles and the oil looks like you just poured it in. Any engine anymore should ideally be shut off when it's not being worked, and thank you Jim for helping me understand that concept because it went against everything i thought i knew about engines.

The website you posted mentions other engine configurations as well, might be worth looking into. If you can get a 140 hp cat engine on it you would never be able to bog it down hahahahahahahahaha
 
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The website you posted mentions other engine configurations as well, might be worth looking into. If you can get a 140 hp cat engine on it you would never be able to bog it down hahahahahahahahaha

That would be nice on the bigger engines, but that adds another $8-$12K to the price, which then starts getting my payments out of whack. Plus, seeing how it's only in the 12" series, if I want a motor that big, move up to the 15" or 18" series and really let it rip!
 
There is something to having torque, but with that big of a difference in power, well power is power. Torque doesn't do work, power does. I'd have to go with the gas because I like all the power I can get in a chipper. I'm sure it will go through tons of fuel though.
 
I wonder how much operator's habits affect fuel use, as well.

How much do chippers get idled down when not actively chipping? I don't recall exactly, because the bit I, personally, used the SP's Brush Bandit, we were consistently feeding it. If I recall, it was basically push the button down twice to idle down, and twice to go back up to full idle. I don't know how that affects longevity of the entire machine. Hydraulics only worked at full throttle. IDK how or why they didn't at lower speeds, physically.
 
California is hard on diesel and emissions.
My older 100 hp Perkins kicks arse and is hella efficient. CA ever catches me using it out side my county, huge fine. Need a 2010 or newer motor. A lot of folks switching over to gas if they buy newer. He'll, even used. Less regulation.
 
I hear the sales people brag how good the gas engines sound....like an old muscle car. Translation - loud. Fun for the first few minutes, if I'm right.

I would do whatever it takes to chip behind the two engines in the model chipper you are planning to buy. After your other research and asking here that will give you clarity you're making the right choice.....or......reveal a surprise you hadn't thought of and steer you to the right choice.
 
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Thanks for those nuggets of wisdom Merle; will have to put the skewer to the dealer to see if that can be done. :thumbup:
 
Hydraulics only worked at full throttle. IDK how or why they didn't at lower speeds, physically.
My take on it : physically they can, excepted perhaps at idle, but the builders don't want for two reasons I think.
First, at a lower speed, the cutting disk/rotor has way less power stored in it, as the speed comes in as a square factor. So it can do way less cutting before bogging down or even stalling. Same with the motor, less powerful of course, so it can't supply what the disk needs and has trouble to keep or recover its rotational speed.
Second, the air flow generated by the disk wouldn't be strong enough to blow correctly the chips out by the chute, with a high risk of clogging, or at least a poor length of spitting out the chips. This point isn't relevant if the chipper has a conveyor at the output, but often (from what I have seen in the vids), only the very big ones are such equipped.
 
I understand why the chipper wouldn't physically chip well, if run too low, but I don't understand how the machine itself is configured, hydraulically and electrically, to make it so.
 
Fairly simple really Sean, a sensor shuts down the hydraulic infeed under a certain revs (usually of the cutter wheel where it has a speed sensor) It’s all spool valves and stuff.

On tickover most machines will be able to turn the rollers outwards but not inwards for safety reasons.
 
As am I, my brother though is very good at this stuff (supplies and fits auto steer systems to tractors)

He’s the smart one.
 
Fairly simple really Sean, a sensor shuts down the hydraulic infeed under a certain revs (usually of the cutter wheel where it has a speed sensor) It’s all spool valves and stuff.

On tickover most machines will be able to turn the rollers outwards but not inwards for safety reasons.

That's what I have on my small chipper. A magnetic sensor is triggered by a steel star mounted on the cutter's shaft. An electronic module counts the pulses and activate an electric valve on the inward hydraulic hose (which is fed by the main manual hydraulic distributor "out-stop-in-stop"). If not activated the valve sends the oil directly to the tank. If activated, the oil under pressure goes to the motor of the infeed roller. The electric valve is bypassed by a one way valve allowing the flow in reverse, so the infeed roller can still turn backward even if the cutting rotor is slowing and shutting down the supply of the inward flow.
That's a neat feature because if you notice that the engine is bogging down by a chunk jamming the rotor, you can quickly put the roller in reverse and try to extract the offender, even if the feeding is already shut. That can save you the trouble of opening the cutting chamber and freeing the rotor, which is a real pain on some chippers.
 
A friend bought a gas Bandit 250 size with a small block Chevy. Haven't heard reports yet. Sounds great.
 
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