Altitude change from 5200ft to 650ft above sea level.

[datanull]

Are diesel tractors tuned differently for higher vs lower altitude? If I move a the tractor from high to low altitude will I need to need to change anything?

I don't know the exact model and size. I know it is newer JD but I don't know HP etc. I will supply more info when I learn more.

Thanks to all!

 

[RoyJackson]

I know they make less HP at high altitudes, but rather your particular brand of tractor is adjusted to compensate (if possible with normally aspirated engines) is a good question for your dealer.
If anything, I'd think they'd be leaned out a bit to keep the correct air/fuel ratio.

 

[SPYDERLK]

If your tractor is a normally aspirated diesel set up for hi altitude it could use a bit richer fuel charge at the lower altitude. If its not set for hi alt, but for regular "generic" [low] alt youll not benefit from fuel adjustment. You will just notice more power and less smoke at the new low alt with no fuel adjustment. If your tractor is a turbo it will perform almost exactly the same either way.
larry

 

[kjung17]

Look at your exhaust when under load. White smoke indicates a lean condition. Black smoke is a rich condition. I suspect, you will notice reduced black exhaust smoke at lower altitudes, as well as the HP gain that Roy mentioned.

 

[BethesdaEC]

Probably depends on how old your tractor is. Modern cars since mid 80's or so have a lot of sensors to compensate for different altitudes and temperatures automatically. Not sure when that tech hit tractors but I suspect that my 2010 JD 2520 probably automatically adjusts.

 

[kjung17]

The Computer controlled engines with multiple injection events, Variable geometry turbos and EGR valves will, certainly, adjust for maximum performance. The 4.5 liter JD is the smallest engine that has these features. The small tractors are still using up carbon credits and do not meet any emission Tier requirements.

 

[RoyJackson]

The Computer controlled engines with multiple injection events, Variable geometry turbos and EGR valves will, certainly, adjust for maximum performance. The 4.5 liter JD is the smallest engine that has these features.

Just out of curiousity, do you know that as a fact? Or is it just conjecture?

 

[kjung17]

I do a fair bit of training for Deere. I'm pretty sure, say 90%, about the 4045 engine being the smallest Tier III engine. I did not look up the sensor set up on the smaller tractors, but, again, I don't recall any advanced features on the small tractors. There may be high altitude software for the larger machines that I am unaware of. I'll have time for more thorough research this evening.

Curiosity got the best of me. Did a little research while eating my chili.
1) There does not appear to be any info on high altitude tuning for diesel engines on the Deere website.
2) I overlooked Spyder's post earlier. He has it right. Turbo units make their own atmosphere and are not really effected by altitude.
3) The 3029 and 4024 (3 cylinder 2.9 and 4 cylinder 2.4) engines will also meet a variety of Tier requirements. The 4024H can meet interim Tier IV requirements.
4) There is nothing on the emissions chart under 48 hp or 2.4 liters.

 

[RoyJackson]

I do a fair bit of training for Deere. I'm pretty sure, say 90%, about the 4045 engine being the smallest Tier III engine. I did not look up the sensor set up on the smaller tractors, but, again, I don't recall any advanced features on the small tractors. There may be high altitude software for the larger machines that I am unaware of. I'll have time for more thorough research this evening.

Actually, just curious about the Deere built engines, not the Yanmars.
I'm pretty sure (from the Deere website) that the Yanmar engines are Tier III or Tier IV emissions controlled (but I haven't looked on the Deere website recently).
I am just curious...but I don't think those Deere engines (in the new 4xxx series machines) would be capable of the automatic altitude compensation without some type of dealer or technician work.
Again, just curious...this information doesn't apply to me...

 

[kjung17]

Actually, just curious about the Deere built engines, not the Yanmars.
I'm pretty sure (from the Deere website) that the Yanmar engines are Tier III or Tier IV emissions controlled (but I haven't looked on the Deere website recently).
I am just curious...but I don't think those Deere engines (in the new 4xxx series machines) would be capable of the automatic altitude compensation without some type of dealer or technician work.
Again, just curious...this information doesn't apply to me...

I added a few notes to my earlier post.
Here is the chart from the Deere site:
Search
There is only 2.5 psi difference from sea level to 5000 feet. Diesel engines do not appear to be effected as much as gas engines due to the higher compression ratio and thermal efficiency.

 

[Raspy]

Diesels engines are always inherently lean burning. That is, unless they are under full load and then you see some smoke. Brown is fine, but black means excess fuel that is not getting burned completely. This is the best indicator of the engine being at full power for a given RPM. Remember, they always take in a full charge of air, then the fuel is added to start combustion. At higher altitudes, they get less air, so they might smoke more at full load and lose about 3% of their power or so for every 1000' elevation. The mixture is constantly changing and can't be discussed in the same way as a gasser. There is no such thing as lean or rich adjustments on a diesel, that is what the throttle does. It's more about how aggressive the fueling ramps up and the maximum fuel delivered. Smoking does not necessarily mean rich.

White smoke at startup means cold cylinder walls and moisture with incomplete combustion. Brown smoke means good combustion and about 75% output. Black smoke means full power and either excessive fuel or poor atomization. It can also mean a bad injector if the engine is not putting out much power and smoking.

Turbocharged diesels with mechanical injection often have barometric compensators that ramp up the fuel based on intake manifold pressure. These should not smoke so much and should produce about the same power at altitude.

High pressure common rail injection diesels with turbo chargers measure the intake air temperature and the manifold pressure to select the right amount of injection and should smoke even less while producing good power. The computer gathers information and refers to a chart, or fuel map, to decide how long to leave the injectors energized for a given RPM and throttle position.

 

[Snaker]

I have an older Yanmar diesel 4 stroke and the manual makes no mention of altitude compensation. I'm not a diesel expert by any means, but I can tell say that the throttle on my machine controls the fuel only. The air intake to the valves is in a constant "wide open" condition so the cylinders will pull in all the air they need. That would suggest that the engine is designed to handle a varying air/fuel mixture that is always changing based on throttle position (little fuel-lot of air or lot of fuel-lot of air) vs. gasoline where the air/fuel mixture is kept relatively equal as the throttle controls both fuel and air.

If my theory is right then you would just be dealing with adjusting for power/smoke as others here have discussed if needed.

Side note: My last couple of snowmobile purchases have been used mountain rentals brought down to the flatlands. Step 1. on those gasoline 2 strokes is to change carb jets to richen or the engine will be toast.

 

[BethesdaEC]

I remember on my '79 Dodge van with a 318 engine, there was a section talking about re-tuning if the vehicle was going to be permanently operated at high altitude. New cars are so much easier, my 2000 Sable Wagon first and only maintainance item outside of fluids and filters was to change the spark plugs at 100K miles. Seemed I was changing the plugs, caps and wires every 30K miles back in the day, then the timing lights and idle adjustments, I don't miss it all.

 

[CowwFace]

I'm with Raspy on this one...

We live at 8500' and I've had my Ford F250 Diesel since 2004 with no adjustments (Cripes who know's how many computers are stuck in there??) but also my 2009 Kioti DK40SE and no adjustments.... one thing is the Glow Plugs seem to be very important up here for cooler starts (even in summer).. but otherwise no adjustments ...

If you're moving to LOWER elevation, sounds like you get to enjoy some more horses ... But what about the snow... you will miss the snow!!!


Tractor on

 

[Raspy]

Yeah, glow plugs are needed more at higher elevations, regardless of the temperature. With less atmospheric pressure there is less air in the cylinders and lower compression pressure. So, less compression heat to fire the fuel. Some engines are borderline starters anyway and as soon as there is a lower temp in the cylinder, for any reason, they need help. This is more the case with pre-combustion designs than with direct injection because there is more surface area for cooling compared to the volume of air. So, the compressed air cannot get hot enough to reliably start.

Diesels are often looked at through gas engine eyes and easily misunderstood.

 

[Jerry/MT]

Are diesel tractors tuned differently for higher vs lower altitude? If I move a the tractor from high to low altitude will I need to need to change anything?

I don't know the exact model and size. I know it is newer JD but I don't know HP etc. I will supply more info when I learn more.

Thanks to all!

My understanding of the way a normally aspirated diesel is controled is that when you set a throttle position you command an rpm level. As you increase the load, the governor adds fuel and allows a little bit of speed "droop".
As you continue to increase the load the fuel flow increases (and the speed "droops") until it reaches the ammount limited the inability to burn the increased fuel due to a lack of oxygen. This would cause a lot of black smoke and no more useful power could be produced. Since you cannot add anymore energy( because the fuel won't burn) to produce work, it's a self limiting situation.
There would be no need to worry about adjusting the injector pump going from higher elevations to lower elevations.

 

[Raspy]

Some governors work that way, as in generators and are called isochronous governors. And the droop is kept to a minimum. But in vehicles the governor is more likely to simply control the maximum and minimum RPM, while the throttle controls the rest of the range. This keeps the engine from going to full throttle with a slight change in the throttle pedal position and improves driveability.

The pumps are set up to only add as much fuel as the engine can burn. But then, at higher altitude, or while lugging, you can get some smoke. And smoke is not necessarily a bad thing. It just means the engine is producing all the power it can at that RPM. Not a huge black cloud, but a dark haze. Smoke is a fact of life with diesels at full power. If the atomization was better, it might produce the same power with a bit less smoke. Then catalytic converters and diesel particulate filters are added to reduce smoke and allow power.

A turbo is a better way to add power by simply pumping in more air and therefore allowing more fuel to be added, which pumps in more air yet and allows even more fuel, etc, until it's limit is reached.

 

[KennyG]

There is only 2.5 psi difference from sea level to 5000 feet. Diesel engines do not appear to be effected as much as gas engines due to the higher compression ratio and thermal efficiency.

Going back to basic Internal Combustion Engine theory, effect should be about the same on both gas and diesel normally asperated engines. The power (at a given engine speed) is directly related to the BMEP (brake mean effective pressure) in the cylinder. This is then directly related to the atmospheric pressure x compression ratio. If you reduce atmospheric pressure by 2.5 psi, that's 17%. Just googling around, I quickly found recommendations for stationary (generator) diesel engines to derate by 3% for every 1000 feet of elevation, which is consistent.

 

[MMH]

Raspy's right on!

Black smoke out of a diesel simply means that it is overfuled (more fuel being injected than the engine can burn). Short termoverfueling occurs in turbo'd engines when the increased load demand is initilly demanded. As the turbo spools up & delivers the air, the overfueled condition is eliminated. Continuous overfueling is bad - the combustion chamber gets very hot. Continuous overfueling often occurs when simple injection pump modifications are made w/ no other changes.

If the original poster is going from higher altitude operation to lower altitude, no modifications should be necessary. If he was overfueled before, he no longer will be (or not to as great an extent). He will simple enjoy more power & less black smoke!