Tractor Performance: diesel vs gas

[Soundguy]

So, what you are saying is that you really have no idea what the longevity is??

Years.. .. I did say years.. does that count as a time period for you? or whatever planet you are from.. do they use light years?

The peanut gallery just got some breathing masks. It smells as if the performer was out playing with a skunk.

These acerbic quips are uncalled for and truly detract from the threads here.

I'm going to make an adjustment that will greatly increase the reading pleasure for myself anyway..

{click}

Ahh.. that's better.

soundguy

 

[Egon]

Years ehh!

So the tractor will easily run twenty four hours a day for 365 days a year for 10 years ?? That's how the years thing shakes out!

And back in the peanut gallery the performer starts wondering why he appointed the lowlife despicable fellows down there as his conscience.

 

[JSharp]

But the gassers offer NO advantage whatsoever. Why bother. Rebuilds are no more complex on diesels, injector pumps get done by shops, so why bother with gassers.

If you're talking about older small tractors, say 50HP and under and 1970 and older, the gas units do have advantages.

 

[Jerry/MT]

Howdy all, new to the forum here.

I'm planning to buy a smallish farm tractor, prolly less than 50 HP. I'm interested in opinions about the difference between diesel and gas engines, in regards to overall tractor performance. What preference do you have and why?

- djb

If you are planning to buy new, I'm afraid you'll have to buy a diesel since I know of no new gas powered tractors. I believe the early '80's saw the last of the gas powered tractors offered by OEM.
Personally, I believe diesel is a better way to go from a thermal efficiency standpoint and a maintenance standpoint. The high compression ratios (16-18:1 or greater)of the diesel lend itself to better fuel eficiency because of about a 10% better thermal efficiency just from the use of the diesel cycle. This is particularly true at part load because the spark ignition engine uses a throttle plate to control speed while the diesel engine is controled by controling fuel flow with a wide open induction system.

The diesel engine is a bit more complicated than a spark ignition engine but the owner won't realize that because the engineering of the engine has dealt with those issues.

With no ignition system to deal with, the only regular scheduled engine maintenance is changing the oil and filter, making sure the air filter is clean, changing or servicing the coolant, and changing the fuel filters. Of course since the EPA is in charge of regulating air quality, in their infinite wisdom, they are requiring more stringent emmision controls on farm tractors, so there is that issue to deal with. Removing sulphur from the fuel is a good thing for the engine durability viewpoint but the resulting lack of fuel lubricity and the slight(~0.5-1.0 %) reduction in LHV of the fuel due to the desulphuring process ( not the removal of sulphr per se) has required special fuel additives be added by refiners and fuel efficiency to decrease by ~0.5-1.0 %. It will also add some additional maintenance because of the special devices that are added to the engine.

One down side of the diesel is the cold starting capability for those of us who live in the cold parts of the world. this can be greatly alieviated by the use of block heaters and making sure that the battery charging system is working correctly. The spark ignition engine with its more volatile fuels and lower compression ratios (~8:1) is certainly easier to start in sub zero tempreatures relative to a diesel.

in my opinion, it's not a hard choice to choose between a diesel or a gas tractor. I'd choose a diesel, hands down!

I hope you find this helpful.

 

[Soundguy]

I believe the early '80's saw the last of the gas powered tractors offered by OEM..

CC had one in the late 90's..

soundguy

 

[WilliamBos]

CC had one in the late 90's..

soundguy

I think he is referring to AG/Utility tractors, not CUT/SCUT.

 

[intel]

I am an engineer and i believe the bus drivers

 

[Jerry/MT]

CC had one in the late 90's..

soundguy

CC, who is that?

 

[Soundguy]

Cub Cadet. I didn't see where you had specified ag/utility.. or i wouldn't have offered that as a possibility. But CC did have a ? big scut.. or small cut as a gasser. In the late 90's I remember looking at one at an agco dealers lot... cute.. and I like things with spark plug wires... I can usually get them to run without any (high magic)..

soundguy

 

[RalphVa]

I definitely like diesels: can do most jobs with less hp than gas because of big torque of the diesel; they start INSTANTLY (after proper glow plugging, etc.)(this is vs. carbureted gas; fuel-injected gas will start the same); they use less fuel, about 50% less than a carbureted gas; combine this lower fuel consumption with lower needed hp and you really save fuel.

In a 3,000# car, for instance, a 100 hp diesel is great; whereas, you need about a 125-140 hp gas engine one for the same performance.

Ralph