Is it time for a gasoline engine tractor?

[Oldpath05]

Knowing what I don't know now, if I had the choice of buying gas or diesel tractor, I'd pick the one that's significantly the quietest, fuel consumption would come in sec. Same if I was buying a new pickup, when ever I walk by a diesel pickup, I can hear it 200ft away, for me, motor noise is good if I was driving a 1962 Ford Thunderbird, but on anything else I want quiet, might have to wait for Dylithium Crystal power.

 

[bigdeano]

My brother and I have a total of 5 gas tractors, no diesels. They work just fine, don't seem to burn a lot of fuel so it's not a factor. I like the quiet and lack of diesel smell. The two 75 year old MMs aren't real quiet, but still quieter than diesels. One of them runs a 6' rear mower on my 5 acres of unused pasture.

A new diesel tractor would have some advantages, like a live pto and hydro drive, but it's not worth the price to change for me. Would like to have a new gas tractor just as much.

 

[Turbys_1700]

IF only you was as smart as you would like the folks here, to think you are...

In MANY places, including here, ag diesel is available right at the pump, just take a can and fill it with what ever amount you want... I buy mine from the same station I buy all of my fuel...

I'll help you out with a "hint", it's RED!

SR

Yes, that's not an issue here either. Several stations handle off road diesel. I've got a 50 gallon tank with a pump I utilize on the back of my truck to fill with off road diesel.

 

[vsteel]

I can assure you my very new mtd mower does indeed have a throttle, and can be run at more than one engine speed!

What is the hp limit on your "small engines dont have to comply" statement?

Gas tractors from 9-30 hp have done lots of work in the last 70 years...

As for life expectancy.. I'd say gassers started out goid then dropped in the 70's and are now coming back.

Running, working gasser antiques testify to that.

Is your MTD a push mower or a rider? I was thinking push mowers, I have not seen a push mower in a while that didn't just have an on and off switch. Not saying I am an expert but just showing my point that small gas engines to meet regulations are specially setup to work at rated and not much else. The carburetors are adjusted for rated and not meant to be variable like the old days. Lots of smaller motors now are going EFI just to meet the standards.

I think you misunderstood what I said, current tier 4 regulations break "Nonroad Spark-Ignition Engines 19 Kilowatts and Below" down into different levels based on engine size, year, EPA phase, and if it is hand held or not. They also break out things like marine generators. What I was meaning is that a small lawnmower motor doesn't have to meet the same standards that a larger motor you would find in a tractor does.

I would disagree with your life expectancy, I would say gassers have been on a steady climb since day one but in the 60s diesels overtook gas and stayed ahead but have been losing ground to the gas motors.

I don't disagree that gas tractors can do the work, I am merely talking about the differences between gas and diesel engines and why diesel gained favor a long time ago.

In 1990 my father bought an 8200 Heston windrower and got it with a gas engine. It was one of 6 built (or that is what we were told) that year and I think it was the next year that they dropped the gas option. Just not enough demand.

 

[vsteel]

Lets not forget the Oliver 770 was a 1958 to 1967 vintage low compression carburated gasser burning leaded fuel and produced 12.25 HP per hour per gallon of gasoline , 4.3 gallons per hour at full power to make 50.0HP.
The diesel made 14.5 HP per gallon per hour and used 3.4 gallons of high sulphur per hour to make 48.8HP.
Those are Nebraska tests b.t.w.
Taking a wild guess the fuel tank held maybe 25 gallons ?
In the grand scheme of things having to refuel every 5-1/2 hrs instead of every 7hrs is not that big of a deal. In particular when gasoline has been cheaper than diesel the past 9-10 years.
Getting back to engines of 2016 instead of the 1950's. Today's direct injection high compression gas operating on cheaper gasoline would put the 1950's Waukesha diesel to shame. For those of you who like to compare modern diesels to old gassers. Turn about is fairplay.

The tanks on those were 20 gallon.

I didn't know you were a Waukesha fan. For those that don't know on the Oliver Waukesha engines, the diesel engines and the gas engines were basically the same motor. So your example of 4.3 to 3.4 further proves that in very similar motors the diesel fuel usage is less in this case.

I will disagree with your refueling comment. When you are working the machine for weeks on end then yes, refueling time is a big deal. That is time you could have the wheels turning trying to make money.

Sure the direct injection high compression engine would put the old Waukesha engine to shame (though it wouldn't do it with the style and hum of the Waukesha) a modern turbo high fuel pressure diesel would put an old engine to shame as well. I was comparing similar era engines, old vs old.

Something else that has not been brought up. When storing gasoline above ground or non protected you can lose a lot of fuel from evaporation. For example the University of North Dakota did a study showing in a non protected 300 gallon tank you could loose 10 gallons a month of gasoline but the diesel rate was small enough it wasn't a concern. Gasoline that was subject to evaporation had an effect on fuel quality where diesel didn't show any difference.

 

[buickanddeere]

I just got 250 gallons of diesel delivered for my new tank at $1.399 a gallon. Well, it was two months ago when the price was at the bottom. Red died. No paperwork...
About two years worth for me, and I figured diesel was good for two years. Actually I'll probably get it topped off next summer.
Would I do this with gasoline? Not even with ethanol free.

Clearly older lower compression tractor engines seem to run on almost anything you put in. My experience with engines under 20hp is very different though. Only exception seems to be my "real" Hondas, not Chondas, which always start. Granted I dose them with SeaFoam, etc.

I'm at 250 hours with my diesel X750 JD GT and I flat out love the thing. I do find fuel usage goes up substantially when run at higher rpm, so i try to slow it down a bit, and keep my blades sharp so I can.

What about torque and HP concerns? Haven't diesels always put out more torque? Isnt that what we really want with our tractors? Though I was surprised to find the spec on my 23hp Vanguard that I repowered my Gravely with was almost the same torque as my diesel JD. But I'm guessing that torque comes in at higher rpm. But then one mows at higher rpm...

Torque doesn't do work. Force over distance with relation to time is a measure of work. When you say torque, are you referring to torque rise when lugged down during an overload condition ? With a hydrostatic or powershift machine the point is mute.

 

[buickanddeere]

Whilst gas motors for tractors again are a possibility, if they were practical they would be in semi's and Ford/Dodge/GM would be plastering the TV with ads about their big block, high torque, gas 3/4 ton trucks. There is no law saying you can't rip out the diesel in your Kubota and bolt in a 454 Chevy to get rid of the emmisions krap, have at it.... But I bet the diesel was and is the best choice.... Probably the ' next big thing ' will be battery powered tractors for lower hp machines.. have to plug it in for an hour or so a couple times a day..

because the Semi truck is a HD applications with a duty cycle near full rpm and full power. The CUT, forklift, manlift, car and light truck are light duty application at part throttle and part load. I am being to think that some people don't know the difference ? Or they are so devoted to diesel since the 1950's they don't want to face what the EPA has done to a good engine and will again in 2019 with tier V?

 

[buickanddeere]

Summer Diesel or Winter Diesel?

Purchase a few jugs at a time to keep from getting caught with summer diesel in the tank during the winter.

 

[buickanddeere]

This argument has played out over the last 100 years, gas lost a long time ago; more expensive, hard to store, dangerous to use, has less energy, costs more to refine, and gas engines don't produce the toque need to do jobs a tractor performs, gas engines require more maintenance, and are shorter lived. It's a no brainier it's diesel. Oh, by the way a clean diesel produces way less CO2 then gas, just added that for a modern twist. HS

Your story would stand in 1970 with low compression gassers using carbs, point ignition and leaded fuel. Now it's now 2016 with Tier IV . Gassers in 2016 unlike 1970 are high compression, direct injected and use unleaded fuel. Diesels now in 2016 unlike in 1970 are loaded with EGR, delayed injection, glow plugs, turbo, variable waste gate, particulate filter, urea injection, two batteries, gelled fuel an complex/expensive filtration.

 

[buickanddeere]

IF only you was as smart as you would like the folks here, to think you are...

In MANY places, including here, ag diesel is available right at the pump, just take a can and fill it with what ever amount you want... I buy mine from the same station I buy all of my fuel...

I'll help you out with a "hint", it's RED!

SR

No red pumps here at the truck and car gas stations.

 

[jmc]

Torque doesn't do work. Force over distance with relation to time is a measure of work. When you say torque, are you referring to torque rise when lugged down during an overload condition ? With a hydrostatic or powershift machine the point is mute.

Actually, the units of work and units of torque are the same: pound(force)-feet, for example. Work per unit of time, as you mentioned, is power. Power and work are totally different. A rat in a squirrel cage can plow a field if the gearing is right and we give him enough time.

 

[Oldpath05]

Yes and a pound of diesel weighs more then a pound of gas

 

[jmc]

The other thing about gas vs diesel efficiency, besides fuel BTU content and compression ratios, might be the higher gear ratio to get a gasoline engine's sweet spot RPM down to a useful RPM on a tractor. For example, my old Ford 1920- 34ish engine HP deteriorated to 29ish HP at the PTO. So, say 20% drivetrain loss from gear friction (and churning the oil bath). I think gear train frictional loss is proportional to the gear reduction ratio, so if you have to take 3600 RPM on a gasser down to what works at 1800 RPM on a diesel, you've doubled the frictional geartrain loss- no small deal.

 

[Jerry/MT]

Considering all the angst and disappointment over TIER IV diesel engines and tractors, is it time for a manufacturer to bring back a gas engine tractor? I mean, they worked well for lots of years under lots of conditions.

My understanding is that Kubota currently sells gas engines to repower diesel tractors?

Those of us who farm and ranch are being done a great disservice by the EPA with emission controls for farm tractors. Farm tractors are minimal contributors to air pollution and the expense driven into the purchase cost and the cost of ownership is much greater than any perceived benefit. But if you have regulators their gonna' regulate.

 

[Redneck in training]

This argument has played out over the last 100 years, gas lost a long time ago; more expensive, hard to store, dangerous to use, has less energy, costs more to refine, and gas engines don't produce the toque need to do jobs a tractor performs, gas engines require more maintenance, and are shorter lived. It's a no brainier it's diesel. Oh, by the way a clean diesel produces way less CO2 then gas, just added that for a modern twist. HS

And can run on various fuels.

 

[Redneck in training]

The other thing about gas vs diesel efficiency, besides fuel BTU content and compression ratios, might be the higher gear ratio to get a gasoline engine's sweet spot RPM down to a useful RPM on a tractor. For example, my old Ford 1920- 34ish engine HP deteriorated to 29ish HP at the PTO. So, say 20% drivetrain loss from gear friction (and churning the oil bath). I think gear train frictional loss is proportional to the gear reduction ratio, so if you have to take 3600 RPM on a gasser down to what works at 1800 RPM on a diesel, you've doubled the frictional geartrain loss- no small deal.

I don't think that is correct statement. PTO rpm is set by manufacturer little past of the maximum torque (near best specific fuel consumption) while maximum power is produced at much higher rpm. Google performance curves for the engine to see what I am talking about.
Here is example Kubota EA330 - Kubota Model EA330 Diesel Engines - EA Series Engine

The lowest fuel consumption is between 2000 and 2400 rpm. Maximum torque is at about 2000 rpm. So gears for PTO will provide 540 rpm at about 2400 - 2500 rpm because (for stable operation) you want the torque to rise if rpm start decreasing due to high load.

 

[buickanddeere]

The other thing about gas vs diesel efficiency, besides fuel BTU content and compression ratios, might be the higher gear ratio to get a gasoline engine's sweet spot RPM down to a useful RPM on a tractor. For example, my old Ford 1920- 34ish engine HP deteriorated to 29ish HP at the PTO. So, say 20% drivetrain loss from gear friction (and churning the oil bath). I think gear train frictional loss is proportional to the gear reduction ratio, so if you have to take 3600 RPM on a gasser down to what works at 1800 RPM on a diesel, you've doubled the frictional geartrain loss- no small deal.

Farm tractors all ran similar or identical rpms for the gas and diesel versions.
Just as a point Yanmar has made a 3600rpm single cyclinder air cooled diesel for decades. is it a lousy performer ?

 

[buickanddeere]

And can run on various fuels.

Grandpa's old all fuel AR would run on gasoline, moonshine, paint thinner, kerosene, #1 diesel and #2 diesel. Now that is "flex-fuel". Try those various fuels in a Tier IV EPA diesel.

If the EPA had stopped at Tier II instead of current Tier IV and going to Tier V in 2019. It would be all moot point as Tier II Diesels would be the preferred engine in most applications with gas usually a distant 2nd.

 

[Redneck in training]

Grandpa's old all fuel AR would run on gasoline, moonshine, paint thinner, kerosene, #1 diesel and #2 diesel. Now that is "flex-fuel". Try those various fuels in a Tier IV EPA diesel.

If the EPA had stopped at Tier II instead of current Tier IV and going to Tier V in 2019. It would be all moot point as Tier II Diesels would be the preferred engine in most applications with gas usually a distant 2nd.

I have two diesel pumps in opposite directions in about 12 miles from the farm. One sells both red and normal diesel and the other sells bio-diesel. So once a while I buy bio-diesel because I am in town. Didn't see difference in tractor performance.
Bio-diesel produces much cleaner exhaust than normal diesel. I was working on some equipment my employer supplied to underground ore mine in Canada. Switching to bio-diesel significantly improved air quality underground. Initially it was total disaster because the bio dissolved all the crud in tanks and fuel system plugging filters, injectors etc. but after all was clean they said they will never go back to normal diesel.

 

[daugen]

I'm told running biodiesel can smell like popcorn.
while I believe there is nothing like the smell of diesel in the morning,
popcorn would be ok...

what is the cost difference between Number 2 and biodiesel? More than one type/grade of biodiesel I assume too.
Now if you also owned a restaurant, you could use your old cooking oil after some good filtering.

Those older tractors with the large propane tanks; could they stay out in the fields all day? For most of what most of us do, as not "real" farmers, capacity not much of an issue. And I already have a big propane tank on the property. There are some small handtools that run on those camping propane bottles. Since you can't recycle them, or get them refilled, seems an odd solution. But...I think the propane powered hand tools and small mower were a direct result of gasoline powered equipment not starting. I think the gasoline issue may be more of an issue in the Northern states where mowers, weedeaters, etc get used for a smaller portion of the year. Then they sit.

what there should be is a law where all gas engines have to have a fuel shutoff. Then you could run them dry easily, though I've read that's not a cure-all either.

For point of discussion, could we all agree to comparing gas and diesel for a 50hp CUT? Something most of us might have?
Could the best source of proven gas engines for long term use be the engines they use in propane generators, which are converted car engines?

And don't tractors normally have inline engines versus V for compactness? I know Cat 3208's were used in tractors, maybe not for long, of course no engine could be wider than the tires on a tractor... So what inline gas engines are we thinking of? Are we ready for gas turbo fours in our tractors?

With both my tractor and my diesel lawn mower I have to wear ear protection or it's just really tiring after an hour or two.
Would be nice to have a quieter alternative. But not as nice as good performance and much better fuel economy.

Would be nice to see some stats on tractors currently offered with both gas and diesel in the same hp, and see what
today's real world is like, not what many of us remember from 30 or 40 years ago.