Turbo or no turbo

[Grapeman]

I've been looking at new Kubota Grand L 40's. Was interested in a 5240 with cab or a 4740. The 5240 has a turbo and makes 52 hp with the same engine as the 4740 which is normally aspirated. I've had many tractors over the years but have never one with a turbo. We tend to keep good tractors just about forever unless they are traded to make a deal on a newer one. I'd like the extra horses but I am concerned about the long term care and maint. on a turbo. What are the pros and cons?

 

[art]

The turbo's have proven to be good for adding horsepower and when nobody plays with the injection pumps they have a good life span without any additional maintanence. I'm not afraid to use them and with my toys I'm continually trying to add them for the additional power they can give at a reasonable cost.

Turbo's have been around for many years and will probably be used more in the future with the price of fuel.

 

[Bird]

I can't claim to have any technical knowledge at all, but from what I've been told, read, etc., it seems that a turbo on a diesel engine increases both power and fuel economy with the only drawback being that you need to let the engine idle a few minutes before shutting it off if it's been running hard.

On the other hand, a turbo on a gasoline engine is another matter. I've driven a couple and it's a blast; unblieveable power and acceleration, but worse fuel economy instead of better, and a shortened engine life.

Now, with my limited knowledge, I could be wrong, but I like a turbo on a diesel, but would want a supercharger rather than a turbocharger on a gasoline engine.

 

[Wesdor]

Thank you Bird for those extra details.

I just ordered a turbo diesel tractor yesterday and did a lot of checking to see that it wouldn't cause the same kinds of problems in gas autos.

What I did not realize is that it would improve the fuel efficiency. I respect your experience and words here at TBN and can now add another plus to the decision I made.

Thanks again.

 

[SDT]

GM:

Aside from an engineer, I've been a mechanic for nearly 50 years and have tried to avoid turbos on the equipment that I plan to keep long term, be it highway or farm related.

Though mature technology, a turbo is simply another rather expensive component that will eventually require service or replacement. I prefer displacement rather than turbocharging to produce HP.

That said, compact tractors have small displacement engines and most of those available on the market above the lower HP ratings do have turbos, limiting the selection of machines that could be considered high HP compacts.

SDT

 

[Bob_Young]

One Pro is that the turbocharged engine will make its rated power regardless of the outside ambient air pressure. This is a huge boon to operators in high altitude areas. Probably not so much down in the NY grape district where elevations run less than 1000' MSL. But you probably would find that the TC engine delivers its rated power more consistently day-to-day regardless of what the barometer's doing.

Turbochargers are also being added in response to new emission requirements. The same sized engine rated for the same power as last year is suddenly spec'd out with a turbocharger for 2008. I'm not sure how that works. Has the TC been added to improve combustion efficiency and thereby reduce emissions or has it been added to make up for power loss resulting from emission controls?

As one who rarely runs his tractors at rated power, the turbocharger seems to be just another potential maintenance headache. As SDT says, something else to worry about. If the tractor was delivering rated power more than 30-40% of the time, I might find a turbocharger justifiable because I'd really need all the HP I bought.
FWIW
Bob

 

[Bird]

I agree that it is true that adding a turbo is something else that can go wrong and cause problems, but that's true of each and every accessory or improvement added to anything. How many people want a bare bones car? No air-conditioner, no power steering or brakes, no power windows or mirrors or door locks, few or no instruments on the dash, etc. I'm old enough that I used to own cars and pickups like that, but not anymore.

Now there's certainly nothing wrong with a bare bones car or tractor. If it meets your needs and budget, it's the right thing to do. But of course, there's a reason that Ford, GM, and Chrysler all have turbos on their diesel pickups; not to mention almost every over the road truck being built today. And I reckon the same is true for tractor manufacturers.

 

[SkyPup]

I've currently got four turbodiesels with Garrett turbochargers that are >10 years old and have not had single solitary problem with any of them.

I would, however, recommend the use of full synthetic oil at all times to keep the turbo bearings happy!

 

[bandit67]

I think that turbos are going to be a very common standard fixture on the majority of engines in years to come. They take an otherwise useless waste byproduct and convert it into additional energy, thus increasing fuel efficiency and power. Those two factors alone are going to be very important in coming years as crude oil issues continue.

Yes, turbos do blow up. I had one go on my 7.3L after only 30k miles, but it was because it was taxed at this altitude and working heavy loads. I replaced it with a better turbo, added a bunch of power, and it's still going strong at 60k+ miles. Thats on an engine that puts out 350 RWHP, which translates to close to 450 flywheel hp.

I don't think too many tractor engines are going to tax a turbo to the extent that a truck engine does, so I'd feel completely confident in buying a tractor with a turbo. As a matter of fact, I kind of wish Kubota had a small turbo engine in the 30 hp range, but at 8500' above sea level, I would make much better use out of a turbocharged engine than most sea level folks would.

 

[brandoro]

I have had turbos on gas and diesel engines. The gas one was incredibly powerfull for its displacement but burned fuel like a big V8. They add fuel for power and more fuel to help cool things. Not efficient at all but hard to wipe that stupid grin off your face.
My point of view, a diesel engine with a turbo is all good. Better fuel economy, lower emissions and more power. Both turbo diesels I had were the Dodge D-50 (Mitsubishi) trucks. Put lots of miles on both, no issues at all with the engines. I ran synthetic oil and made sure they were idled or driven gently for the last few minutes before shutting down. Don't be powering your heaviest load all afternoon when it is 98F outside then shut it off. It only takes a couple of minutes to pull all that extra heat out of the engine and turbo bearing. Chrysler had a good idea when they started putting turbos on some of their small cars, they included the turbo bearing in the water jacket. Made them sort of idiot proof. I try to never underestimate the ingenuity of fools.