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So I have a new 9330, and when pulling an average load, (22' disk ripper, approx 5.5 mph), I like to run 1800-1850 RPM. I have had people, including techs from JD tell me I should be running 2,000 rpm instead! This goes the same for my 9320 also. I just cant justify the extra 200 rpm's + the extra fuel it would be using, since I'm at the top speed I can physically run in the ground I'm working. Should I kick the throttle up? Or stay at the lower eng speed I've been running? What are your opinions?
 

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I know it dosnt have all the crap on it but our 9200 has spent most of its life working between 1600 and 1900 rpm depending on what work its doing.

Madsnake
 

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If you want to satisfy the left coast types that crammed all the emission controls onto the tractor then rev it up. otherwise run it at 1800 rpm if the tractor can handle the load.

The 9630T I got to demo this spring burned an extra 100 litres over what my 9420 did while pulling the same implement. I think the new 13.5 is a bit of a hog on fuel anyways.
 

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Well thanks for the input. I generally run 1900+ if I'm pulling really deep, or a lot of weight in the air seeder. Otherwise, I run even in the 1700's if I'm just pulling a field cultivator, disk, or doing real light chisel work. I was just confused, since a couple hired hands were saying that a John Deere mech. told them to run it at 2000+ ALWAYS. The question arose when we had to spend $10,000 in engine work on the 9320 last year, right while we were trying to plant wheat. One of them was wondering about the cause of the problem, and thinking that it was because the engine is generally run at lower rpm's.
 

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I was told the engine needs to be run wide open as it helps it clear out the exhaust that is being recirculated, therefore longer engine life.

No idea why they would say to run your 9320 the same way.
 

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It's interesting that ag techs recomend running engines at full speed always when on the hyway trucks loaded to over 135000 lb will run all day at 1350 rpm. I read in a 3406 Cat engine manual that you could run that engine down to 1000 rpm full load for up to 30sec and Cummins N14 didn't seem to care where you ran as long as you didn't overheat it. Todays new electronic engines will compensate for the demands you put on it. I ran a test on a new truck in 07 with mounted equipment that ran off the truck engine thruogh the transmission in a stationary application. The equipment used about 378hp to operate. We had a Cat technition hook his computer to the truck engine (a 478hp C15 Accert twin turbo) and monitor engine load and fuel consumption. With the engine running at 1800 rpm (1:1 transmission ratio)it showed about 67% load and 24gph fuel consumption then we changed to high gear (.73:1 overdrive ratio) and the engine load increased to about 70% and fuel consumption droped to 18gph. I've rebuilt, repaired, and troubleshooted alot of engines and to be honest with you I've only seen a few that I believe have been possibly damaged from overloading at low engine speeds (melted piston tops) and most if not all of those were probably severly overheated at one time or another. One very important note though that I find almost everybody overlooks is monitor your coolant conditioner level. Diesel engines run at very high combustion temperatures and what happens is the coolant is basiclly boiling at the cylinder walls, this causes erosion or pitting of the cylinder walls and an expensive repair. Your operators manuals cover this and will also cover how to best operate and maintain your engines and equipment also. Read your manuals they do have your best intrest in mind I believe. Remember alot of technitions don't run the equipment they work on, some have never run equipment at all. Each the ones with race cars, they deal with gas engines (speed equal power), look at diesel engine power and torque curves, best torque 12 to 1500 rpm, best power 16 to 1800 rpm, why rate them at those speeds if you can't run them there? Remember clean air, fuel, and oil, oil between the add and full marks, temp 185 to 220f, coolant conditioner in the recomended zone you will have a happy troublefree engine. Good luck!
 

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So on one hand, Deere says to run the throttle wide open, yet their engineering department hails the advent of IVT, which allows faster field speed operations at lower engine rpms.
 

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we run our 8400 and 8520T at 1500-1600 rpm most of the time and run about 5.5-6.5 mph

we try to always shift up a gear and drop the rpms as long as the tractor can take it and not over heat it and not give it to much of a load
 

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Today I leaned over been running tractors wrong my whole life. 8650 and 9300 always trained to run around 2100 rpm under load.
 

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Ill see if i can explain this properly without a picture but if you could get a graph of the engine hp and torque it would help explain and you would want to run the rpm where the hp and torque curves intersect. Its my understanding that is the point where the engine is running most efficient. Throttle up you get more hp and burn more fuel, if things get soft engine lugs down and you get to peak torque also burning more fuel. This info was also before all the emissions came in so its possible engines need to run differently now to keep emmission equipment functioning properly but thats where id run it...
 

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Ill see if i can explain this properly without a picture but if you could get a graph of the engine hp and torque it would help explain and you would want to run the rpm where the hp and torque curves intersect. Its my understanding that is the point where the engine is running most efficient. Throttle up you get more hp and burn more fuel, if things get soft engine lugs down and you get to peak torque also burning more fuel. This info was also before all the emissions came in so its possible engines need to run differently now to keep emmission equipment functioning properly but thats where id run it...
It also depends on how much of the power your using for what rpm you should run at. Our tj500 got best economy around 1850-1900 pulling the drill. Our newer T9.615 is different you can run 1700 if it’s easy pulling to get best economy but if it’s pulling harder you get better in a lower gear and 1900rpm. This is the dyno chart for the T9.615 we are using the lower power tune.
 

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The effiency manager will drop the Rpms down too 1700+ - from 1900 and the poweshift will take over ..

She’ll lug that big Deere down and pul all day .. this is a 2014 9560R ... 1/2 gallon a acre pulling a boat anchor 60’ concord
 

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The torque curve on most newer engines is lower than 20-40 years ago. Fuel economy is one reason. But as the rpm goes down the torque goes up to arrive at a given HP. All systems slow down at lower rpm, like coolant flow, oil volume in engine and transmission, hydraulic flow, cooling fan. I like the 1450 to 1650 rpm for less wear, less noise, less fuel consumption if the engine is not lugging. Translation - If you go to full throttle and the engine responds by immediately revving up to higher rpm, you are probably ok. If not, you need to shift to a lower gear, lower speed or higher rpm. That maximum torque continuously and the heat in the entire system will shorten the life of every component.
I will try to post a HP rating chart for Iveco industrial diesels.
 

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The torque curve on most newer engines is lower than 20-40 years ago. Fuel economy is one reason. But as the rpm goes down the torque goes up to arrive at a given HP. All systems slow down at lower rpm, like coolant flow, oil volume in engine and transmission, hydraulic flow, cooling fan. I like the 1450 to 1650 rpm for less wear, less noise, less fuel consumption if the engine is not lugging. Translation - If you go to full throttle and the engine responds by immediately revving up to higher rpm, you are probably ok. If not, you need to shift to a lower gear, lower speed or higher rpm. That maximum torque continuously and the heat in the entire system will shorten the life of every component.
I will try to post a HP rating chart for Iveco industrial diesels.
Not anything to do with the newer ones, but when you mention the older engines, lots of younger guys today aren't aware that many of the older engines can't handle the lower RPMs of today. Perfect example was that Versy 750 I bought for parts, besides having been a wreck at some point and the front frames all bent up, it had a very serious knock in the engine. Young fellow that had it, after just rebuilding one hole in it for a knocked out wrist pin, decided to get a different tractor. After I got it home, not that I wanted to blow it up, but I wanted to find out just what was exactly going on, figured it had a loose wrist pin or broken piston again, and while loading and more I had never cracked it above an idle. So finally with the rocker covers off, I gives her full throttle and besides the horrendous clattering in my ears I noticed something instantly, it only reved to 1650 RPM. Then I got looking and saw that at some point the throttle cable had broke right at the pump and had been jerryrigged, but now couldn't get close to full throttle. Since I thought it would be educational for the young fella, I phoned him up and asked him about it, and thats when he told me that yea he had done that, but his friend a mechanic had told him it was no problem running an 855 at that low of RPM under load.....and therein lay the problem, a later Big Cam or N14, absolutely, but the older Small Cam like that engine was, 220 actually no turbo, lugging at low RPM is the quickest way to kill one other than to melt it down with too much fuel. I felt bad for the kid as he soon realized it had been preventable and was now an expensive lesson and thanked me for explaining it to him. And I have talked to a lot of other younger guys who don't realize there is a difference either. Its not one speed fits all.
 

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When I was in tech school the one instructor (worked for Cummins for a few years) said that the V8 Cummins in the 4wd hardly had any troubles if they were wound out. Most issues came from guys lugging the engine at low rpm.
 

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Really depends on the engine. Don't know how the emissions will last at lower rpm, for better or worse. Some V8s as stated above like it reved up. Some such as an older IH didn't last running to fast. If I run my old steiger with 3208 fast it doesn't run well at all. It also just doesn't run that great. My 20 year old CAT runs at 1500-1700 all the time. They lug down fairly well and it hardly ever gets worked hard anyway. I only burn 3 acres or so per gallon seeding with it. Makes my combines look like fuel hogs. No answer on that engine from me.
 

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I have always used a very simple formula for picking gear selection and rpm on a field tractor. If the engine rpm drops more than 10% from no load to loaded, it is time to gear down and throttle up. This should also include the power it takes to run the hydraulic pump (fans on an airdrill).
On a highway tractor watching the pyrometer temperature will tell you if your are working the engine too hard.
Short bursts of working hard are not going to wreck an engine; it is the prolonged hard running that will cause problems.
 
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