Geo Tracker Kubota Diesel Engine Swap

[Diesel_Dave]

Originally Posted by Varn

If it isnt the flame front then surly it is something else. Probably run away heat.

In a spark ignited engine, the combustion process is limited by flame speed because the flame is propogating through a premixed miture (limited by chemistry). In a diesel, the combustion process is limited by the mixing process--the air needs to get to the fuel before it can burn (limited by fluid motion). At some point it just can't mix fast enough to burn all the fuel. That's why you can't typically spin a diesel as fast as a gasser.

[DieselDrewski]

Originally Posted by Cobb

I think in its oem un fooled around with design most diesels are safe in that regards. I have seen a youtube video where an old diesel seeked an alternative fuel source (ether and crank case oil) it ran away and spun a few bearings til someone choked it off, but as a newbie I cant post it here.

Its my understanding most engines have a sweet spot and really the lower of an rpms you can dial it in the more power and efficiency you will have. I heard back on my shop days inthe mid90s that it took 75 hp alone to spin a tradational v8 push rod lifter/cam shaft over 5000 rpms.

A diesel runaway is a pretty violent event. There are indeed a few good videos on YouTube.

[hawk2100n]

From a thermodynamic perspective, diesel is assumed to be a constant pressure expansion where the slow rate of burn for diesel causes the gas to expand at almost the same rate as the piston falls and expands the volume in the cylinder. This constant expansion is due to the heavier weight of diesel and its reduced volatility, which is the speed which it turns to a vapor. So diesel injects into a very hot cylinder and burns slowly. Gasoline has had time to vaporize, especially riding in through intake and compression cycles so it burns nearly instantaneously. This allows the engines to easily rev much higher, see 14k rpm sport bikes that you see tooling around town.

The comparisons of diesel engines cannot really be made because BMW's amazing 6 cylinder diesel engines have rev lines of 6000 RPM now. What enables this is careful metering of fuel delivery at EXTREMELY high pressures (30,000 psi +) which allows the fuel to atomize smaller and vaporize quicker. This allows them to make 300+ hp in a 3.0L 6 cylinder under extreme emissions restrictions. On the other hand, the JCB diesel max used the JCB 444 engine as its base, a 4.4L 8 valve industrial power plant which in its most potent form develops 77 HP. It's amazing that they made it make 750 hp however that was at over 250 psi of boost, 12 to 1 compression and clouds of white smoke and constant glow plugs at anything less than full throttle. Watch the videos. And a Mercedes 5 cylinder uses per-chambers which allowed MB to get by with relatively low injection pressures (2000 psi range). All of the air would be compressed into a small external chamber to allow sufficient heating to burn the fuel. The burning mixture did its best to expand out of that chamber and into the cylinder to make power. Since there is restriction preventing the rapid expansion of gas, the engine cannot rev high. So bottom line is that the Mercedes engines really don't have any power to rev high but this has been overcome with modern direct injection systems in high performance applications. I had a w123 300TD turbo for a while and I am very familiar with that engine specifically. A legend for endurance but not so much for power or efficiency. It got 27 mpg on a good day. I tried and I don't think I ever got to 4000 rpm because I was feeling guilty for the enormous cloud of black smoke spewing out of the back from an otherwise smokeless car. And I had about a minute to think about what I was doing while the car accelerated from 3000 to 4000.

[cRiPpLe_rOoStEr]

That's an interesting project to say the least. Any update? BTW an uncle of mine had a 4-door Suzuki Vitara (same as the 1st-gen Tracker) with a Volkswagen 1.6IDI and, even not able to go faster than 85MPH, was good. Using low-quality Diesel fuel it could easily get 42MPG inner-city and 48 on highway, not hypermiling.

Originally Posted by bandit86

I want a kubota in my land rover

Those V2203 used in Thermo King semi-trailer reefer units are a good option.

[Christ]

Originally Posted by cRiPpLe_rOoStEr

That's an interesting project to say the least. Any update? BTW an uncle of mine had a 4-door Suzuki Vitara (same as the 1st-gen Tracker) with a Volkswagen 1.6IDI and, even not able to go faster than 85MPH, was good. Using low-quality Diesel fuel it could easily get 42MPG inner-city and 48 on highway, not hypermiling.




Those V2203 used in Thermo King semi-trailer reefer units are a good option.

Do you have any means to import engines from your homeland to the US? I understand you guys end up with a lot of the "better" engine types (diesel stuff) than we get here, it'd be nice if you could import a crate of "parts", yano?

In any event, I rarely use road fuel in my engines. I've used everything from alcohol mixes to raw gas to motor oil/transfluid,etc and various blends thereof.

[cRiPpLe_rOoStEr]

Originally Posted by Christ

Do you have any means to import engines from your homeland to the US? I understand you guys end up with a lot of the "better" engine types (diesel stuff) than we get here, it'd be nice if you could import a crate of "parts", yano?

In any event, I rarely use road fuel in my engines. I've used everything from alcohol mixes to raw gas to motor oil/transfluid,etc and various blends thereof.

Shipping would be the most complicated deal. Also, automotive light diesels are not so easy to get in Brazil as it is in Argentina, Uruguay and Paraguay, or Europe where Diesels are never outfashioned.

[Varn]

Remember that Brazil uses recyclable fuels namely 80% ethanol.

I was in venezuela and Peru in the late 90's. In Peru gas was higher than US prices at the time and venezuela a nearby country sold gas for .50 cents a gallon. ....deleted political comment...

[cRiPpLe_rOoStEr]

Originally Posted by Varn

Remember that Brazil uses recyclable fuels namely 80% ethanol.

I was in venezuela and Peru in the late 90's. In Peru gas was higher than US prices at the time and venezuela a nearby country sold gas for .50 cents a gallon. ....deleted political comment...

I'm not really an ethanol die-hard fanboy, unless you were talking about cachaça

Gasoline is still way cheaper in Venezuela, but actually its quality is not so great. You might remember that "white recall" promoted by BMW, the so-called "engine campaign" taken in '96 to replace some engines with cylinder sleeves made out of Nikasil because it didn't have a good resistance to the sulphur content from Venezuelan gasoline. Some vehicles even caught on fire in Brazil, Venezuela and the United States, mainly in Florida as far as I remember.

[Varn]

What I amazed at was the large number of US made cars from the 60's and newer particularly SUV's in Venezuela. The bigger the car the more they drove over the centerline. I never took much interest in European brands back then. It took active avoidance to stay out of their way.

One thing I thought was funny was that there were some homemade license plates. Apparently if you lost your plate you just painted a new one.

In discussion about politics down there I was amazed at the hatred for the US. This was before Chavez.

[bigblue12v]

I finally joined! Google led me to your post and I have to join in. I have had a project in the works a while just now getting some parts accumulated. 93 4 door 4wd sidekick auto, converting to 5 speed and putting a Kubota D1402 in front of it, adding turbo. I'm building it into a UTV not an economy vehicle but if all works out well, I'll drive it on the road occasionally. Would like to see some updates and more video on this thing, as well as would love as much help as you can offer on clutch and trans adapter fab. Thanks!
Eric