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Here is an excerpt from a diesel fuel reference I found which was written by Chevron.

D I R E C T-I N J E C T I O N A N D I N D I R E C T-I N J E C T I O N
The two fuel injection processes used in diesel engines, direct-injection (DI)
and indirect-injection (IDI), are illustrated in Figures 6-2 and 6-3. In a DI
engine, fuel is injected directly into the cylinder above the piston. In an IDI
engine, fuel is injected into a small prechamber connected to the cylinder via
a narrow passage that enters the prechamber tangentially. During the compres-sion
process, air is forced through this passage, generating a vigorous swirling
motion in the prechamber. Then fuel is injected into the prechamber and igni-tion
occurs there. The combination of rapidly swirling air in the prechamber
and the jet-like expansion of combustion gases from the prechamber into the
cylinder enhances the mixing and combustion of the fuel and air.
The more rapid mixing of fuel and air achieved in IDI engines comes at a price,
however. The high velocity flow of air through the narrow passage connecting
the main cylinder to the prechamber, as well as the vigorous swirling motion
in the prechamber itself, causes the air to lose significantly more heat during
compression than it does in a DI engine. Coupled with a pressure drop from
the main chamber to the prechamber, this results in an air temperature in the
prechamber after compression that is lower than that in a similar DI engine.
Since rapid fuel autoignition requires a certain air temperature, an IDI engine
needs a higher compression ratio to achieve the desired air temperature in
the prechamber. IDI engines operate at compression ratios of about 20:1 to
24:1; while DI engines operate at ratios of about 15:1 to 18:1. The heat losses
that necessitate these higher compression ratios have another, more impor-tant
effect: they decrease the efficiency of the engine. IDI engines typically achieve fuel efficiencies that are 10% to 20% lower, on a relative basis, than
comparable DI engines.
Even with the higher compression ratios, IDI engines may still be hard to start.
Most IDI engines use glow plugs to heat the air in the prechamber in order to
make starting easier. Glow plugs, which are small resistive heaters, are usually
powered for only the first few minutes of engine operation.
With the negative attributes of harder starting and lower efficiency, one may
wonder why IDI diesel engines are used at all. The answer is engine speed. As
an engine gets smaller, generally it must operate at higher speeds to generate
the desired power. As engine speed increases, there is less time per engine
cycle to inject, vaporize, mix, and combust the fuel. As a result, the higher
mixing rates afforded by IDI designs become necessary to achieve good
combustion at higher engine speeds. IDI diesels most commonly are used in
smaller automotive and light duty truck applications.

Ran out of Diesel filled it up and now it won 039t start
Cub Cadet
Replies 20 Post by MJB

JeffM: I did have the same issue with the rockshaft not lifting the hoe quite high enough to align the holes for the L-pins. I adjusted the plates you referred to such that when the 3ph is in the full up position the holes line up perfectly to allow the L-pins to just slip in. Works great. I also found it easier on my machine (4300 with R-4s) to slip the L-pins through from the inside to the outside and snap the lock pins on the outside of the frame. Hope this helps.

JD 48 Backhoe Complaint
John Deere Tractors
Replies 20 Post by MJB

On JD 4000 series tractors other than the 4100 the 3rd SCV is also typically used to raise the mid mower deck. If you want to keep your FEL attached and operational at the same time as your mid mower you will need the 3rd SCV. I think that the 4100 uses the TPH to raise the mower.

Third Selective Control Valve
Operating and Attachments
Replies 9 Post by MJB

This post is in regards to the question of direct vs. indirect diesel injection. Being a Case tractor collector I have read several articles regarding the early development of diesel engines used on Case tractors in the early 1950s. Case developed an indirect injection diesel, which used what was called a "Lanova Power Cell". When the piston approached TDC the injector would spray a jet of fuel horizontally across the top of the piston into the "Power Cell", which was a pre-ignition chamber on the opposite side of the cylinder. The fuel would ignite and begin to burn in this chamber and the resulting expansion would blow the burning air-fuel mixture back into the cylinder thus giving a more thorough mixing of the fuel and air. This design was used because although it was more expensive to produce, it was more fuel-efficient than the early direct injection designs. Case continued to use this design until it became necessary to turbo-charge their engines to compete with other manufacturers published horsepower numbers. The Lanova indirect injection diesels do not take to turbos very well. It seems that as the pressure in the cylinder is increased by the turbo, the fuel penetration into the "power cell" drops off. This tended to concentrate the fuel in a single spot on top of the piston creating a hot spot that could burn a hole in the piston. To overcome this limitation, Case switched to direct injection diesels at this time for both turbo and naturally aspirated engines. This also gave them the benefits of simplicity, lower cost, and commonality of parts. I believe that with improvements in injector and pump designs the modern direct injection diesels are as efficient as the indirect injection engines. I don't know what the reasoning is for Kubota and some other manufacturers to continue to use the indirect injection design. MJB

Horse power to horse power
Operating and Attachments
Replies 24 Post by MJB

Art
Not all 6 Volt systems are positiove ground. Right now I have a 1947 Willys CJ2A which is 6 volt negative ground. I also have a 1952 Case DC-4 tractor which was 6 volt negative ground before I converted it to 12 volt operation. The other older cars that I am familiar with seem to be about evenly split between positive and negative ground on 6 volt systems. When 12 volt systems first came out I think there were a few instances where they used positive ground as well. Sure makes you pay attention when you hook up a battery charger. MJB

positive battery ground
Parts and Repair
Replies 19 Post by MJB

My uncle has an Allis Chalmer G. It is a small cultivator tractor with a four cylinder flathead gas engine at the rear of the tractor. It has mid mounted cultivators which are in plain sight of the driver because he sits right above them. He also has a 5 foot mid mounded sickle bar mower for it. With the engine at the back and without the cultivators mounted you can easily lift the front wheels off the ground by hand. These tractors are still very popular among pototo and onion farmers around here (Central New York) and still command a good price if you can find one for sale. The tractor dosent have anything like a three point hitch on it anywhere. The cultivators are manually lifted by a long handle which also raises a bar across the back of the tractor meant for an additional set of cultivators. MJB

Center mounted 3-pt tractor
Tractor Projects
Replies 3 Post by MJB

Jim... I would not advise putting calcium chloride in a tubeless rim and tire for any length of time. The calcium will eat through the metal rim at a rate that is not to be believed. Since all the corrosion is happening from the inside out you might not be able to tell if the rim is getting to thin until the tire blows right off. I would not want to be anywhere around the tractor when that happened. If you need liquid weight in the wheels you might take a look at using one of the non-toxic antifreezes on the market. That stuff will not hurt the rims or the grass if it leaks out. MJB

Tire Ballast
Parts and Repair
Replies 16 Post by MJB

Tom is probably right about the diameter of the cylinders being the same for the boom lift and the bucket roll, however these cylinders will not exert the same force. Any hydraulic cylinder will exert more force in extension than in retraction due the surface area available on the face of the piston in the cylinder. On the rod end of the cylinder the surface area of the piston is reduced by the area that the rod takes up, and given the same hydraulic pressure, less area equals less force. Therefore the loader will have more force lifting the boom than lowering and more force dumping the bucket than rolling back. If you look at some older loader designs made many years ago you will see that some reversed the position of the bucket attachment points such that the loader arms attached to the upper pins and the bucket cylinders attached to the lower pins. This would give greater force when rolling the bucket back than with dumping, which of course is probably more usefull design. Why did they change? Don't know. Maybe it costs more, or makes the buckets weaker, or probably because having the cylinders above the lift arms keeps them more out of harms way. Anyway my father has a little MF 1020 with an Allied loader on it that exibits the same lack of downforce on the loader boom but I have never found it to be a significant problem when digging. In order to increase the downforce with the boom you would have to adjust the relief to a higher setting, which of course might cause the bucket or lift arms to get bent under heavy use instead of just stalling the hydraulics. MJB

Loader down force
Loaders Back Hoes
Replies 15 Post by MJB

Thanks for the info. I see you got the turf tires on yours. Do the turf tires squat with all the weight on them? I was planning on getting the R4s in order to handle the weight of the loader and hoe. I expect I will have to be carefull about turning when mowing the lawn howerver. Has anyone out there mowed with a JD4400 with the new front axle and R4s? Thanks MJB

JD4400 owners journal
John Deere Tractors
Replies 26 Post by MJB