Regeneration

[GregP27]

I have to laugh at the thought of low RPM causing cylinder wear. I really didn't and don't mean idle all the time. I mean, there's NO reason to run at 2,800 rpm. Most jobs can be handled at 1,500 - 1,800 - 2,000 rpm, and don't require running it up to max rpm for the entire day. I have no problem saying that if I am idling all day, I might not need a tractor. But I also don't need to run at 2,500 rpm all the time, either.

Most engines have a "sweet spot" near cruise, where they just seem to run happily. I doubt seriously it's anywhere near max rpm.

Like I said above, go drive a Mahindra around, with no DPF. You don't really idle it around unless you are hooking up an implement, but there's no need to thrash it, either. If someone wants me to run one near max rpm all the time, I smell a former used car salesman who moved to tractors and laughs as his mechanics rake in the money from repairs, all the while blaming it on the DPF instead of the nut driving it.

Some engines have a lot of stress at idle. I used to work on WW2 aircraft engines; Allison V-1710's to be exact. They have 4 rings on the piston, and some of the early boat hydroplane racers used to remove the lower ring to make changing pistons easier. It had the side effect of making the pistons able to flop around in the bore down near idle and cause premature wear. It also cracked cylinder liners eventually, and I mean within 150 hours. But, the real wear at idle on a stock piston with all 4 rings was the rod bearings since each cylinder produces 150 HP and slaps the crankshaft pretty hard near idle.

But we're talking 25 - 60 Hp engines, not a 1,600 HP 12-cylinder unit. If it makes 28 HP and had 4 cylinders, that's 7 HP per hole, and that isn't going to tear up rod bearings unless they're made out of plastic. I suspect they aren't and also suspect nobody is removing the lower ring, if it even has one. So, idle doesn't hurt the engine for normal periods. By normal periods. I mean startup and warm-up to low green range ( at least to where you can feel the crankcase start to warm up with you hand), and then hooking up implements. If you are idling about a lot, you aren't doing any work and there is no reason to run the tractor. Shut it off and go do something else useful. But many jobs can be handled at medium rpm.

Let me put it like this. My brother in law has a John Deere lawn tractor (gas). His nephew occasional used to cut the lawn, but we all noticed he ran the engine up to high speed when mowing. He doesn't use it anymore because of that. When I did it, I ran above idle, up in mid-range and it use a LOT less gas, did the job well, and seems MUCH happier (a lot less trips to the shop, and belts last longer, too). So, I think a diesel running at 1,500 - 2,000 rpm would be fine for most things until more power was needed to do the job. If so, I have no issue with that. But getting on and pushing the throttle all the way up the entire time is plain old stupid, as any competent mechanic can tell you.

My brother use to be on tugboats. Most were 1,500 to 8,500 HP and all were diesel. You can bet your bottom dollar that THEY didn't run them at full speed unless if was necessary. They usually idled for several hours a day, and ran at cruise speed for most jobs, but also went to full power when needed, which was not often, but DID occur on a regular basis. These diesels that idled for several hours or more a day lasted 50 - 75 years! Yes, they DID sometimes require work and sometimes even overhaul; but NOBODY was concerned about idle speed. It did more harm to start one up cold than it did to idle all day, according to the manufacturers and the chief mechanics. That would be Fairbanks-Morse, Detroit Diesel, GM and many others.

I have been leaning Kioti for a long time; and like the brand. But I will take a hard look t Mahindra when I go to buy just because of no DPF. A DPF LOOKS just like the choked-off 1970s cars that were a nightmare because they sold unrefined emissions engines as required by the government. I'm not saying lower emissions was a bad thing; but they started selling them before they had it figured out. Those cars were awful and failed a LOT. A MUCH better solution would have been to give reasonable time to invent the engines and then cut them in.

It looks like they're doing the same to diesel tractors and we're paying for it.

Maybe we can invent an engine that runs on CO2 and smog and puts out Oxygen as a waste product. Then we could sell half and half!

 

[xcgreene]

I have to laugh at the thought of low RPM causing cylinder wear. I really didn't and don't mean idle all the time. I mean, there's NO reason to run at 2,800 rpm. Most jobs can be handled at 1,500 - 1,800 - 2,000 rpm, and don't require running it up to max rpm for the entire day. I have no problem saying that if I am idling all day, I might not need a tractor. But I also don't need to run at 2,500 rpm all the time, either.

Most engines have a "sweet spot" near cruise, where they just seem to run happily. I doubt seriously it's anywhere near max rpm.

Like I said above, go drive a Mahindra around, with no DPF. You don't really idle it around unless you are hooking up an implement, but there's no need to thrash it, either. If someone wants me to run one near max rpm all the time, I smell a former used car salesman who moved to tractors and laughs as his mechanics rake in the money from repairs, all the while blaming it on the DPF instead of the nut driving it.

Some engines have a lot of stress at idle. I used to work on WW2 aircraft engines; Allison V-1710's to be exact. They have 4 rings on the piston, and some of the early boat hydroplane racers used to remove the lower ring to make changing pistons easier. It had the side effect of making the pistons able to flop around in the bore down near idle and cause premature wear. It also cracked cylinder liners eventually, and I mean within 150 hours. But, the real wear at idle on a stock piston with all 4 rings was the rod bearings since each cylinder produces 150 HP and slaps the crankshaft pretty hard near idle.

But we're talking 25 - 60 Hp engines, not a 1,600 HP 12-cylinder unit. If it makes 28 HP and had 4 cylinders, that's 7 HP per hole, and that isn't going to tear up rod bearings unless they're made out of plastic. I suspect they aren't and also suspect nobody is removing the lower ring, if it even has one. So, idle doesn't hurt the engine for normal periods. By normal periods. I mean startup and warm-up to low green range ( at least to where you can feel the crankcase start to warm up with you hand), and then hooking up implements. If you are idling about a lot, you aren't doing any work and there is no reason to run the tractor. Shut it off and go do something else useful. But many jobs can be handled at medium rpm.

Let me put it like this. My brother in law has a John Deere lawn tractor (gas). His nephew occasional used to cut the lawn, but we all noticed he ran the engine up to high speed when mowing. He doesn't use it anymore because of that. When I did it, I ran above idle, up in mid-range and it use a LOT less gas, did the job well, and seems MUCH happier (a lot less trips to the shop, and belts last longer, too). So, I think a diesel running at 1,500 - 2,000 rpm would be fine for most things until more power was needed to do the job. If so, I have no issue with that. But getting on and pushing the throttle all the way up the entire time is plain old stupid, as any competent mechanic can tell you.

My brother use to be on tugboats. Most were 1,500 to 8,500 HP and all were diesel. You can bet your bottom dollar that THEY didn't run them at full speed unless if was necessary. They usually idled for several hours a day, and ran at cruise speed for most jobs, but also went to full power when needed, which was not often, but DID occur on a regular basis. These diesels that idled for several hours or more a day lasted 50 - 75 years! Yes, they DID sometimes require work and sometimes even overhaul; but NOBODY was concerned about idle speed. It did more harm to start one up cold than it did to idle all day, according to the manufacturers and the chief mechanics. That would be Fairbanks-Morse, Detroit Diesel, GM and many others.

I have been leaning Kioti for a long time; and like the brand. But I will take a hard look t Mahindra when I go to buy just because of no DPF. A DPF LOOKS just like the choked-off 1970s cars that were a nightmare because they sold unrefined emissions engines as required by the government. I'm not saying lower emissions was a bad thing; but they started selling them before they had it figured out. Those cars were awful and failed a LOT. A MUCH better solution would have been to give reasonable time to invent the engines and then cut them in.

It looks like they're doing the same to diesel tractors and we're paying for it.

Maybe we can invent an engine that runs on CO2 and smog and puts out Oxygen as a waste product. Then we could sell half and half!

To clarify, no one was saying LOW rpm would cause premature wear, we were saying IDLE rpm for extended periods, specifically, could cause extra wear.

You mentioned marine diesels. It's actually a very large issue for marine diesels to run at idle speeds for long periods. Coking up, carbon buildup on valves, turbo sooting, exhaust stack fires due to soot, oil slobbering, jacketwater leaking due to low temps, cylinder temperature deviations causing uneven wear between cylinders and pitting due to exhaust gas condensate and acid corrosion. All symptoms of idle running. Anyone who works extensively with large marine diesels will tell you the same, you need to get your temperatures up. As far as these large diesels lasting 50-75 years, They sure can, but that is not without many complete overhauls including new heads, liners, pistons, bearings, every 24k Hours or so. Working with a number of Alcos, EMD's, MAN's, and smaller CAT's, with well over 300K hrs on them, the only thing left of the original engine from ages ago, would be the block, and possibly crank and some driving gear. Even the new Wartsilas I have here, with now only 30K hrs on them, already have new liners pistons and heads. While conducting these overhauls it's clear to see the differences in the ones that have idled extensively. Make no mistake, running these motors at IDLE for long periods is not good for them.

But as you said, running at a low RPM, (that is above Idle), is perfectly fine, That bit of extra speed makes all the difference.

I also agree that the DPF stuff is a mess, and how they made room for it by putting the fuel tank where they did, my hopes they will figure it all out as time progresses. Daedong was one of the first to dive in after all.


Source: am Chief Engineer Unl Motors.

 

[GregP27]

Gottcha'. I'd let it idle for a reasonable period. But idling for long periods usually means you aren't doing anything, and shutting it off is probably better anyway.

Since my brother is in the marine industry, I know it isn't an issue, at least on tugboats. They do it all the time. Spend some time watching them. I also know it isn't an issue for the world's largest piston engine, the Wartsilla-Sulzer RTA96-C 2-stroke diesel. It idles at 22 rpm and operates at 108 rpm max, at which point it produces 107,390 HP ± a hair. I've seen them idle for days, waiting for an anchorage.

You can draw your own conclusions; I already have. My engines run great, all the time.

As for trucks, they change the idle speed to please the new emissions stuff on them, not because it hurts the engine. Hundreds of thousands used to idle all night frequently, and these were privately-owned, so they weren't doing anything to hurt the trucks. Once you fit them with required emissions stuff, you have to protect THAT stuff, not the engine. And, that stuff is expensive!

 

[xcgreene]

Gottcha'. I'd let it idle for a reasonable period. But idling for long periods usually means you aren't doing anything, and shutting it off is probably better anyway.

Since my brother is in the marine industry, I know it isn't an issue, at least on tugboats. They do it all the time. Spend some time watching them. I also know it isn't an issue for the world's largest piston engine, the Wartsilla-Sulzer RTA96-C 2-stroke diesel. It idles at 22 rpm and operates at 108 rpm max, at which point it produces 107,390 HP ｱ a hair. I've seen them idle for days, waiting for an anchorage.

You can draw your own conclusions; I already have. My engines run great, all the time.

As for trucks, they change the idle speed to please the new emissions stuff on them, not because it hurts the engine. Hundreds of thousands used to idle all night frequently, and these were privately-owned, so they weren't doing anything to hurt the trucks. Once you fit them with required emissions stuff, you have to protect THAT stuff, not the engine. And, that stuff is expensive!

Tug boats typically have two propulsion engines. When they are waiting for long periods, one will be shut down to put more load on the other, this is to prevent cold temps, idling speeds, and extra running hours. If you see a tug at the dock with smoke coming from the stack, it's either from the generator engine, not propulsion, or they are departing within the next 30 minutes.

For a large tanker to sit with the main engine online for days on end would only be to abide by whatever port authority rules are for the location at the time. They may demand the ship to be ready for maneuvering at any given moment, or there may be special anchoring rules at that location. If the vessel is to sit there, main engine idling, they would set up an engine ramp up routine to blow out soot the idling has created, and gain some temperature. To sit at idle for any other reason, the Engine department needs to have a little chat with the Deck department.

As for trucks, running above idle is not a new concept for just emissions add-ons, this has been common practice for years, many long time truck drivers know the importance of maintaining temperature and oil pressure with a higher idle for the benefit of the engine internals.

 

[GregP27]

Whatever. I know a hundred guys who say different in several industries. You, of course make your own decisions. Me, too. And I don't idle even gas engines for long periods, unless I'm stuck in L.A. traffic ... in summer, or have a good reason for doing so. Then, there is little choice.

In point of fact, I am unlikely to operate your tractor or vice versa, though I DO take care of my stuff, unlike a lot of folks.

My whole point was that Mahindra has formed a solution for emissions without a DPF. I might be able to give up linked pedal (autothrottle) for no DPF. It SHOULD make the engine a LOT happier and cheaper to run.

It makes me wonder why the Japanese, Koreans, and US manufacturers have NOT figured out a "no DPF" solution. Mahindra did.

So, while it may be difficult to eliminate the DPF, it reaps benefits for the users in lower costs, better-running engines, and no expensive emissions thing to go bad and be replaced, also costing time. Hard to believe that only ONE manufacturer invested the effort to eliminate it ... but it's true.

Seems worth investigating, at least to me, unless there are so many other apparent issues as to render the "no DPF" thing a non-issue due to otherwise poor quality that out-trumps the no-DPF thing. To date, I haven't seen that firmly demonstrated. I even watched one video over in Mahindra where the customer was taking the dealer to task for not picking up his tractor for warranty work for free.

Unfortunately for him I have some knowledge of this and I don't know ANY dealers that do that for free for the normal customer. They are usually understaffed, slammed for work, (or needing work: feast or famine, depending on time of year and crop status), and must use comparatively-expensive equipment to safely haul tractors of 35+ HP. Not may dealers use a 1/2 ton pickup for the job!

Usually only customers do that.

Otherwise, we seem to have a non issue here. You can slam your throttle open at will as soon as it starts. I hope nothing untoward happens, ever. I have no faith in that, though. But, it might work out just fine. Best of luck to you.

I wish we had your lobsters available here. Mr. Maine! And can't find Scrod for love nor money.

Cheers.

 

[neopheous]

I have a 2016 CK4010 and I just had the first regen while bush hogging at 28.6 hrs. I didn't even know it was doing it until it sounded like a pinging in the engine. I was running at about 2100 RPM's and mowing a ditch line at about a 25 degree angle and at first I thought it was something like an oil pump going out and not getting oil to the engine. So I brought it up on level ground and then seen the light. Not even sure what the light should look like but I assume that was what it was. It was red and looked like the breath from old man winter or something... I raised the RPM's to 24-2500 and kept mowing. I could smell it after about 5 min. Almost had a sorta sweet smell to me. It stayed in regen for probably 25 min or so and then went off. I heard that slight pinging sound the whole time until it stopped. I don't idle a lot other than loading implements, or if I get off the tractor for a couple min. Otherwise I run between 1500-2100 most of the time.

 

[GregP27]

Sounds reasonable, neopheous. I probably operate about the same, when I do.

And I really have no issue with xcgreene. Everyone is free to operate their unit as they want to do so and, as I stated. You can't do much real work at idle anyway, so there's little reason for disagreement. I might travel around at 1,500 rpm and take my time rather than thrash the engine, but you have to work it hard enough to get the job done when you are working. And if you aren't working, why are you on the tractor in the first place?

But, if you're pulling a wagon in a parade, you might idle for an hour or more on city streets.

 

[xcgreene]

Sounds reasonable, neopheous. I probably operate about the same, when I do.

And I really have no issue with xcgreene. Everyone is free to operate their unit as they want to do so and, as I stated. You can't do much real work at idle anyway, so there's little reason for disagreement. I might travel around at 1,500 rpm and take my time rather than thrash the engine, but you have to work it hard enough to get the job done when you are working. And if you aren't working, why are you on the tractor in the first place?

But, if you're pulling a wagon in a parade, you might idle for an hour or more on city streets.

Oh no worries GregP27. I was just talking about problems with staying at the lowest idle speed for the engine ~1000 rpm for these tractors, for long periods. 1500 rpm and you are good to go. I apologize if I came across as combative, I don't mean to be. :drink:

 

[GregP27]

Apologize? Absolutely NO need. You posted just fine and I probably said too much about idle.

I tend to idle until the engine block is warn to the touch, and then run at relatively low rpm until the temp gauge is green. Then, run it as you need to run it for the job at hand.

Comes from racing motorcycles and flying small aircraft (admittedly not tractors). My Grandfather's tractor was an old Farmall of some 25 hp, and it was a gas engine, not a diesel. From basic engine data, the engine needs to be warm for all the parts to fit right and run well. That is ... of course OLD wisdom and may not apply to new materials and engines.

But, old habits die hard! As I read about regen and the associated cost when the regen does NOT go correctly, it makes me want a tractor (hopefully new) without a DPF. Perhaps time will tell if the regen equipment averages out to be not an issue or a high cost. I have never seen a study of same. Obviously, if you don't have a regen failure (or warning light), you have no issues. If you DO, you'd be on the "had an issue" side.

It would be REALLY nice to see those data and decide if the regen equipment is an issue (cost / time-wise) or not, once and for all. If not, then it becomes an infrequent, though expensive fault that most never see. If so, Mahindra starts to look a LOT better for their foresight and engineering skills (I have no feeling for their quality, never having driven or closely inspected one). Perhaps THEY could sponsor the study! That would be some good news, huh?

Best regards, - Greg

 

[xcgreene]

A marine engineer by trade, I'm currently on an offshore drilling rig, and I'd be shot for saying this if they heard me, But I've got my eye on the horizon for talk of battery powered, electric tractors. It may sound silly today, sure, but one day it won't. and the next day it will be the norm. Our powerplant here is over 50,000hp diesel electric. Look up IMO 8768361 if curious. The thrusters are electric, drawworks, top drive, everything is electric. There is no doubt electric motors can put down the power needed in a compact size. Once a battery storage solution is properly engineered, there will be no stopping it. With far less parts and drastically cheaper prices, diesel engines, with complicated regen, will eventually be unable to compete.

Its certainly ok to criticize this, but someday we'll all be reading articles like this, from every manufacturer.
John Deere Reveals a Battery-Powered Farm Tractor

I'd bet a dollar or two this has been across the boardroom table at Daedong more than once.