Gallons per hour....

[e.myers]

Tractor I'm looking at says...
2.35 gallons per hour @ 100% load.
What does this mean exactly? What is 100% load?
I don't farm for a living, so cost of fuel is a consideration for me.

Is a smaller HP tractor generally going to use less fuel per hour for the same task with appropriatley sized implements for the tractor HP?

Considering various tractors but in the kubota line I'm scratching my head over grand L 3540 and 3940 and the L4400.... all hydrostats.

Read a thread where this guy was getting bad mileage on a 3240, drained his tires and it improved significantly.

Trying to find that magic HP to weight ratio for x brand tractor.

 

[westcliffe01]

They mean at full rated power, that is the fuel consumption. The only activity that comes close to a load like this would be dragging a heavy plow mile after mile. Most activities may only be 20-30% of rated power with proportionally less fuel consumption.

 

[e.myers]

OK. Thanks, that helps. I was wondering if everytime I ran the bushog, I'd be sucking that much fuel.

 

[MESSMAKER]

I bet I am using way more than 30% of available power when I am Bush hoging.

 

[George2615]

I have a smaller tractor. A 26HP Mahindra. during most jobs such as using brush hog, back blade, rake, plow etc. My tractor uses slightly less than 1 gallon per hour. Fuel tank is 7.9 gallons so I can run about 8 hours on a tank. A higher HP tractor may use more fuel. 2.35 GPH seems high for a 35-40HP tractor but that is at 100% load. I would consider a 100% load use to be a job such as plowing several acres or other continuous duty. Its very rare mine sees 100% duty use. For most of my tractor tasks other than plowing or mowing I run much lower RPM which uses less fuel.

 

[DIRTROAD]

It makes a huge difference if the tractor in question has a turbo or not.

A naturally aspirated tractor will get far better fuel milage than its turbo cousin.

 

[e.myers]

OK I'm starting to understand.
Dirtroad... Is that common wisdom? I would have thought otherwise. The gph figures I gave above are for a 40 hp 3 cylinder turbo (John Deere 4105). If the gph for that is significantly more than a naturally aspirated 4 cylinder 40hp then the bargain I found may not be a bargain. I'm a little leary of a turbo anyway as far as maintenance goes. Maybe the additional 2500 for the Kubota over the Deere is not that much after all.

Still have to decide between 37, 40, and 45hp for my application. Are there any lines between the 3 as to what they can do and can't do?

 

[whistlepig]

OK I'm starting to understand.
Dirtroad... Is that common wisdom? I would have thought otherwise. The gph figures I gave above are for a 40 hp 3 cylinder turbo (John Deere 4105). If the gph for that is significantly more than a naturally aspirated 4 cylinder 40hp then the bargain I found may not be a bargain. I'm a little leary of a turbo anyway as far as maintenance goes. Maybe the additional 2500 for the Kubota over the Deere is not that much after all.

Still have to decide between 37, 40, and 45hp for my application. Are there any lines between the 3 as to what they can do and can't do?

Not for a second would I pick a naturally aspirated motor over a turbo. I don't own a turbo now but have in the past. I really don't need a turbo now. Turbo's are sweet. Gas engine is good. Diesel engine is better. Turbo diesel engine is awesome.

 

[om21braz]

From what I understand, smaller hp tractors now have turbos mainly for emissions compliance. I have a friend with a 1970's IH 1066 w/ turbo - it's never been replaced. That may be the exception and not the rule. Anyway, the mid 20's hp diesel machines I've ran burned approx. 3/4 gal. to maybe 1 1/4 gal. per hour doing various tasks. Good luck on your decision !

 

[westcliffe01]

Sorry, but this is nonsense. Turbodiesel engines have lower friction/hp, higher HP/weight, both of which are critical factors affecting fuel efficiency in a vehicle application. The most fuel efficient engines on the planet are turbodiesel engines and they have held this status since the 30's.

It makes a huge difference if the tractor in question has a turbo or not.

A naturally aspirated tractor will get far better fuel milage than its turbo cousin.

 

[DIRTROAD]

Everyone has their own opinion.

I am just stating what I have observed first hand in my life.

 

[whistlepig]

Sorry, but this is nonsense. Turbodiesel engines have lower friction/hp, higher HP/weight, both of which are critical factors affecting fuel efficiency in a vehicle application. The most fuel efficient engines on the planet are turbodiesel engines and they have held this status since the 30's.

Amen. I couldn't have said it better.

 

[Diamondpilot]

The fuel burn does seem on the high side to me also. My tractor made 31 HP on the pto and burns about .8 gph going so. Its a 3 cylinder diesel, non turbo.

Chris

 

[westcliffe01]

A table showing fuel consumption comparisons can be found here:
Brake specific fuel consumption - Wikipedia, the free encyclopedia

The Junker Jumo Airplane engine held the record from 1931 until another German engine, the TDI from Audi finally beat it in 1990. Today the most efficient engines are the very large ship diesels. Slow speed 2 stroke diesels will most likely always be the most efficient. But the difference between common diesel engines and the Tdi in 1990 was approximately 10% better thermal efficiency. Since the "regular" diesel is only about 30% efficient, a 10% improvement is in fact an improvement of about 30%.

 

[Duffster]

I don't farm for a living, so cost of fuel is a consideration for me.
.

I like to know what that statement means?

It makes a huge difference if the tractor in question has a turbo or not.

A naturally aspirated tractor will get far better fuel milage than its turbo cousin.

I think you got that backwards.

 

[AndyMA]

Everyone has their own opinion.

I am just stating what I have observed first hand in my life.

The problem is when you let opinions rule over facts. Unless you were comparing identical engines under lab conditions I'm not sure how you come to this conclusion.

Turbo diesels are clearly highly efficient as they basically operate as a "smaller" engine until a power boost is required and the turbo kicks in.

Andy

 

[kenstrac]

Since they don't test tractors at the university of Nebraska anymore I don't believe in ANY info that the mfg are throwing at us.

 

[westcliffe01]

You can typically find the fuel consumption curve for the engine at the engine manufacturers website.

As an example, here is the fuel consumption curve for a kubota 1105 NA engine which is rated at 24.8hp.

And below it is the fuel consumption curve for the same engine, but turbocharged, rated at 32.8hp.

At 2200 rpm the specific fuel consumption of both engines is very similar, but at lower or higher speed the naturally aspirated engine will use more fuel than the turbocharged one.

Of course, it needs to be understood that if you use all the power provided by the turbo, you will probably use more fuel than the weaker naturally aspirated engine of the same size. The catch is that you would have to run the weaker engine for a longer time to get the same amount of work done, so you would still end up using more fuel all in all with the naturally aspirated engine.

If you live at a high elevation, the differences between the turbo and naturally aspirated engines become more dramatic. At 7500 ft, you would lose approximately 23% of the performance of a naturally aspirated engine.

 

[MtnViewRanch]

To be fair for comparison, shouldn't the NA engine have the same HP as the turbo? Then with a bigger CI motor, the NA engine is not going to be as fuel efficient as the turbo engine.

There are several tractors out there that are the same machine except the turbo on the engine and the guts that go along with the turbo. I would expect the turbo engine to burn more fuel, it has more power, and it takes fuel to make that power. The capabilities of the turbo tractor far exceed it's non turbo brother.

 

[D7E]

It makes a huge difference if the tractor in question has a turbo or not.

A naturally aspirated tractor will get far better fuel milage than its turbo cousin.

I have to question that ....We've turbo'd our own tractors and improved the fuel consumption because they are not struggling and are "on top of the job" and have turbo'd tractors for customers who say the same.....Many times have had 4cyl turbo's that are better on fuel than a straight 6 of same hp...and sometimes the other way.....Too many variables on make and model and how they are set to say ..!

Take our old cat D7E with that huge 4 cyl turbo 180hp running at 1250rpm uses as much fuel in a day as a 90hp 4cyl natural aspirated tractor thats skidding the logs with it..?

After finnishing tonight and re-fuelling i noticed both tractors are 320hp one has a 14 liter turbo intercooler and the other has a 10 liter turbo intercooler with a few turns of the diesel scew... and very hard pulling on same size cultivators they used exactly the same amount of fuel today just different characteristics the 14 liter will run at 1600 rpm with more low end torque ..but at full tilt i'l say the 10 liter has the most grunt..!
Both do about 10 gal an hour...?