Gas vs diesel vs LP

Does someone here have opinions on the power of these fuels in the same tractor? What I mean is, I have 3 Farmall 450s, gas, diesel and LP. The diesel obviously has the best torque, likes to walk tall. The gas has good throttle response and power, not quite the lugger of my diesel but close. The LP, freshly rebuilt, is the most lackluster of the bunch. Or, it seems to be. Maybe, I need to play around with the LP adjustments a bit more.

Any opinions?

Thanks, Chris B.
 
Diesel fuel=139,000BTUs/gallon
Gasoline !124,000BTUs/gallon
Propane 91330/gallon.
Diesel engines have higher compression ratios, and when burning without over fueling in an efficient engine, are the most efficient (not considering fuel costs)
Gasoline, though less BTUs, and less compression, and when just below the spark knock threshold in timing, can produce more horse power/cubic inch. (many will argue, but this is not racing.)
The propane is at a BTU disadvantage, but can stand a much higher compression ratio than gasoline. When fueled correctly they can be as powerful as gasoline, but much more thursty and considering fuel costs, they come out comparable. This is a generalization, and not going to fit everyone's opinion. Note the diesel in the 450 has less compression than more modern Driect injection style. The gas 450 was designed around what fuel would now be considered 80 or less octane (R+M method)
And the propane engine if equipped with an IH propane head, probably still could use a bit of compression. Jim
 
Thanks. I guess I am searching for a practical opinion, from the driver's seat so to speak. I get the BTU and compression ratio numbers.
 
I also agree your first response lays it all out. I'm not familiar with a 450 diesel. Wouldn't that still be a start on gas, and switch over to diesel? If so, I'm surprised you feel it has the most power. My guess, for the age of those tractors, the gas would be the most powerful. Your propane tractor probably doesn't have enough compression to obtain the power of the other two.
 
Years ago my granddad had a dual fuel tractor. I think it was a Ferguson to35. Ran on Gasoline or Propane. When mowing the pasture it would often not be able to take a full swath with the 5' mower when running on propane in heavy stuff. Switch to gas and it had lots more power.
 
Well if your diesel valves are not recessed, and your gasoline engine is tuned and to spec for timing/mixture (and a tweak on timing), and the Propane tractor is adjusted to spec. your personal seat of the pants is better than most because most don't have all three to compare. Jim
 
Look up the Nebraska test for the 450. I've never looked for the tests on a 450, but have seen Nebraska test information on Super M's. All three (gas, diesel & LP) were tested. You may be surprised at what you find. Super M information surprised me.
 
The diesel engine has more displacement, the LP has to be set while it is on a dyno and something to read the exhaust while under load. The LP can (should) also have more compression.
 
In general

Gasoline has the quick response and get up and go and that is why they use it in cars and pickups.
Diesel has the torque at low rpms's to move huge amounts of weight so they use it in trucks; trains; and large boats.
LP is the dog of the three fuels but it has a place because it burns so clean so they use it for forklifts in a warehouse.
 
My opinion: In older tractors diesels are hard to start when cold and are most fuel efficient under partial load. They tend to be noisier and some have a lot more torque rise under load than others.Gasoline and propane require more ignition maintenance and carburetors and regulators vary a lot in efficiency . Car carburetors are much more efficient than up draft ones.Propane can be efficient ,has less fumes working in buildings, takes longer to refuel ,but you don't have a problem of someone stealing from your fuel tank. At less than half the cost /gallon it is the cheapest even if it has less energy.
 
You probably need to turn your fuel screw out a couple of rounds. Lo. Should be a hair stronger than a gas. I had a 4010 JD LP. Wouldn't start real cold or real hot. Pain in the A. Chainged it to gas. Made it a better tractor but. Not quite a diesel. 4010.
 
The LP should pull the same as either IF it has the propane head and the pistons to give proper compression. Raising compression ratio helps make up for the loss of BTU compared to gasoline by taking advantage of the higher octane rating. Old regulators can and do act up. If you are not getting the pressure you should on the secondary side then it will not deliver enough fuel and you'll be down on power.
 
Can’t we talk about nnalert or religion or politics ?!?
cvphoto52370.jpg

Or even motor oil
 
They should all be equal in power if factory fresh and equipped properly for each fuel type.

I also have three tractors in all three fuel types, but of another brand. They are equal in power. Actually, the LP one is factory rated slightly higher than the others. Currently, my LP tractors are the cheapest to operate due to the fact that I bought propane at 83 cents per gallon last June.
 
One can easily find the Nebraska Tractor Tests for all three machines. They were all tested in spring 1957, so all three tractors tested were probably produced in the same year.

Test 608; Farmall 450 Diesel:
<a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1008&context=tractormuseumlit">https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1008&context=tractormuseumlit</a>
Belt horsepower: 48.78 hp @ 1450 rpm
Specific fuel consumption: .516 lb/hp-hr

Test 612: Farmall 450 Gasoline:
<a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1008&context=tractormuseumlit">https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1008&context=tractormuseumlit</a>
Belt horsepower: 55.28 hp @ 1450 rpm
Specific fuel consumption: .528 lb/hp-hr

Test 620: Farmall 450 LPG:
<a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1021&context=tractormuseumlit">https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1021&context=tractormuseumlit</a>
Belt horsepower: 54.12 hp @ 1450 rpm
Specific fuel consumption: .453
 
Not a BTO but in the BTO business, farm, OTR, heavy equipment......when is the last time you saw an LP or gasoline engine working?l In my STO, I have 5 tractors and all are diesels....having started 40+ years ago, (city boy moving to the country) with a Farmall B, moving up through several gassers and going through a JD 4020 LP, having all diesels currently tell you anything?
 
The 450LP has the factory LP head and manifold, and factory sleeves (NOS IH not aftermarket). The pressure out of the high pressure valve is around 4.5 lbs, spec says 3.5 to 5 lbs as I recall. I had to reset the low pressure lever as that was set too low and too lean.
 
Tells me I'm not looking to debate the gas/diesel thing. I get all those arguments and I would absolutely love to have an 806D. Hard to beat the simplicity of a gas motor, though. My 656 gasser is a smooth operating tractor. If it had 3pt instead of the fixed drawbar, I wouldn't look back.
 
When I was teenager I was privileged to operate a JD 70 lp,a 5 star Moline lp ,a MH 44 lp, MH 33 gas,a Moline zb lp, and a Ferguson 65 diesel, the lp tractors were my favorite, the gas was second then the diesel, as far as exhaust smell. None lacked for power, the implements they pulled were not oversized I guess. This was in the early 70's. Plowing at night with the 5 Star was the best of times. Blackland, a surflex plow,and glowing exhaust.
 
Seems like 8 rounds out. I know that sounds like a lot. But they need to run a little rich to have any power.
 
(quoted from post at 07:08:16 08/04/20) Not a BTO but in the BTO business, farm, OTR, heavy equipment......when is the last time you saw an LP or gasoline engine working?l In my STO, I have 5 tractors and all are diesels....having started 40+ years ago, (city boy moving to the country) with a Farmall B, moving up through several gassers and going through a JD 4020 LP, having all diesels currently tell you anything?

Well then . All those natural gas companies running natural gas in the compressor engines must be some kind of stupid .
Same as all those operators must be out of their minds using spark ignition engines in construction generators , man lifts , forklifts and pumps .
Kubota Mia the headed for bankruptcy by building spark ignition engines up to 100HP for use in any of their equipment.
GM is doomed with a 401HP direct injection gasser for use in light and medium duty trucks . Where the Tier IV diesels are in the shop instead of on the road .
Your apples and oranges comparison leaves out the hours the engine can operate on a limited size fuel tank . Along with ease of handling the fuel .
When Tier V and Tier VI emission regulations are enacted . Small and medium sized applications in light and medium applications will become Jet A-1 kerosene , gasoline , LP ,
Natural Gas and Hydrogen . Instead of # 2 diesel .
 
(quoted from post at 21:12:03 08/04/20)

Well then . All those natural gas companies running natural gas in the compressor engines must be some kind of stupid .

I think operating on FREE NG coming directly from gas well head without transportation/compression costs without the need for a heavy fuel tank to infringe on total carrying capacity isn't exactly similar to utilizing NG over the road or in the field.
 

Due to the simplicity of liquid fuel at atmospheric pressure . Diesel ,
Kerosene or gasoline has to be the fuel used in mobile/long distance applications .
Just switching from #2 diesel to JP-8 or Jet A-1 will cleanup the emissions of a compression ignition engine . The probable next step with Tier V and Tier VI for certain . For engines in HD service
.
Small light duty engines in diesel will be extinct with Tier VI emissions .
 
That's the rest of the story. My gassers always needed this or that. The diesels just run.....nothing to diddle with when you want to use one and that may be 6 months or more from the time you parked it.
 
My tractors aren't current Tier rated so I don't have that problem. My home standby generator is LP and has a 250 gallon tank, gets topped off when I fill the house tank in the fall. Right decision. No problems with that but I had one LP tractor and will not have another.....nor will I have a Regen, or DEF diesel.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top