L39 (or similar) Fuel Consumption

dex3361 · Oct 31, 2011

Your fuel consumption will vary depending on load. Light load less fuel, heavy load more fuel. Here is a good rule of thumb for a tractor and generator for all to chew on. For a diesel engine operated generator you can figure between 0.07 and 0.08 gallons per hour per KW generated when the generator is producing between 25% and 100% of its rated capacity. I have run these numbers against heavy loaded 1000KW (1 megawatt) units and my small 6.5KW unit. So if a 44HP diesel engine driving a 20KW generator under a load of 5KW(25%) then 5x0.08=0.4GPH and 20KW(100%) then 20x0.08=1.6GPH.

So you can figure that a 44HP diesel generator will use 0.4GPH and 1.6GPH dependent on load.

Disclaimer this is a rule of thumb to put you in the ball park.

MHarryE · Oct 31, 2011

Your engine uses 255 grams of fuel per KW-Hr when it is running at full power. I used 7.2 pounds per gallon, so at that density 1 gram = 0.000306 gallons. Full power is 27.9 kW. I think that all calculates out to 2.18 gallons per hour at full power. The numbers from Kubota are for the bare engine - when installed in your tractor there are parasitic losses to be considered so you can't just calculate the ratio between 27.9 kW and your generator, but unless you draw enough power to lug the engine down, you should never go over the 2.18 gph.

Verticaltrx · Oct 31, 2011

If you want a PTO generator by all means get one. The issue of running up hours on an expensive machine shouldn't be of concern to most folks on here. I doubt any of them will put enough hours on a tractor to really wear it out, and especially the engine which is all that's being used for PTO power. My guess is the fuel consumption of your tractor running a PTO generator would be about the same as a gas powered generator half the size.

blueriver · Oct 31, 2011

MHarryE said:
Your engine uses 255 grams of fuel per KW-Hr when it is running at full power. I used 7.2 pounds per gallon, so at that density 1 gram = 0.000306 gallons. Full power is 27.9 kW. I think that all calculates out to 2.18 gallons per hour at full power. The numbers from Kubota are for the bare engine - when installed in your tractor there are parasitic losses to be considered so you can't just calculate the ratio between 27.9 kW and your generator, but unless you draw enough power to lug the engine down, you should never go over the 2.18 gph.

Okay ... grams, pounds, density, Kw, darn talk english ... and by the way if this little Kubota swallows 2.18 gpm .... well time to look else.

stoyan79 · Oct 31, 2011

Get a new Honda genny and don't look back. Very economical, electric start from a distance (inside the house) and will last you a lifetime.

Few years back I was in your shoes and researched the heck out of this. Just get a Honda and be done. Nice ones that will power a whole house are about $2K.

spike23 · Nov 1, 2011

I have had my bx23 on for about 12 hours in the last 3 days and used maybe 6 gallons. You have more hp so I would assume you would be more fuel efficient. One thing though, if you're just using a well pump and refrigerators, a 15kw is way overkill. Mine is a 12, with the pto hp on
my tractor I put out about 8kw. Things actually running at the same time - well pump, water heater, refrigerator, chest freezer, lights, and misc chargers. That's with my little tractor.
I have never understood the "buy a standalone, that's extra maintenance on your tractor.". But if I used 24/7, then I definitely would have a standalone.

PapaPerk · Nov 1, 2011

stoyan79 said:
Get a new Honda genny and don't look back. Very economical, electric start from a distance (inside the house) and will last you a lifetime.

Few years back I was in your shoes and researched the heck out of this. Just get a Honda and be done. Nice ones that will power a whole house are about $2K.

Good advice! Honda can't be beat.

Not sure why he wants to use the tractor with the big diesel roaring and the u-joints whirling.

PapaPerk · Nov 1, 2011

spike23 said:
I have never understood the "buy a standalone, that's extra maintenance on your tractor.". But if I used 24/7, then I definitely would have a standalone.

Because the tractor is needed for other jobs besides running toaster ovens and charging the iPhone. :laughing:

spike23 · Nov 1, 2011

PapaPerk said:
Because the tractor is needed for other jobs besides running toaster ovens and charging the iPhone. :laughing:

No, seriously, explain. When I get home from work at 1am what else am I doing with my tractor? If it's snowing, I'll plow. As I stated, and I think the op expressed, I don't use it 24/7. If I did I would have a standalone. And also I have had my tractor 6 years and have less than 400 hours, so I'm maintaining every year anyway. Sorry I don't live on a farm where my tractor is detrimental to my way of life. If that's your situation then I understand your way of thinking.

avc8130 · Nov 1, 2011

spike23 said:
No, seriously, explain. When I get home from work at 1am what else am I doing with my tractor? If it's snowing, I'll plow. As I stated, and I think the op expressed, I don't use it 24/7. If I did I would have a standalone. And also I have had my tractor 6 years and have less than 400 hours, so I'm maintaining every year anyway. Sorry I don't live on a farm where my tractor is detrimental to my way of life. If that's your situation then I understand your way of thinking.

Truck plows the driveway.

In this storm for example, as would be typical, the tractor was needed for about 30 mins to clear a down branch from the driveway.

EVERYTHING in my house is fine without power for 30 mins. Heck, most of the stuff in my house is fine without power for 8+ HOURS.

People running generators 24/7 must be very accustomed to the "electric" life. The ONLY way I could understand it is if it is very cold and the only heating source requires electricity. (obviously if someone needs an electric machine to assist with LIVING, like breathing or dialysis or something, that is a different story).

ac