Though best known for his invention of the pressure-ignited heat engine that bears his name, the French-born Rudolf Diesel (March 18, 1858 - September 29, 1913) (shown in picture at right) was also an eminent thermal engineer, a connoisseur of the arts, a linguist, and a social theorist. Diesel's inventions have three points in common: They relate to heat transference by natural physical processes or laws; they involve markedly creative mechanical design; and they were initially motivated by the inventor's concept of sociological needs.

Born in Paris, Diesel was the son of a leather merchant. He studied at Munich Polytechnic where he was a sort of renaissance man. Arts, linguistics and social theories then in development all held him in a spell.

One day Diesel saw something strange: A pneumatic cigarette lighter. Small pieces of tinder are in a little glass tube. With a piston, air is compressed in the tube and the tinder starts to glow. This vision set him afire.

He set up a laboratory in Paris in 1885, and took out his first patent in 1892. In August 1893 he went to Augsburg, Germany, where he showed the forerunner of MAN AG (Maschinenfabrik Augsburg-Nuerenberg) a three-meter-long iron cylinder with a piston driving a flywheel. It was an economic thermodynamic engine to replace the steam engine. Diesel called it an atmospheric gas engine, but the name didn't stick.

He worked on. On New Year's Eve 1896 and proudly displayed an engine that had a theoretical efficiency of 75.6 percent. Of course, this theoretical efficiency could not be attained, but there was nothing to equal it—and there is nothing to equal it to this day—in thermodynamic engines.

The self-igniting engine was a sensation of the outgoing century, though Rudolf Diesel's dream of enabling the small craftsmen to withstand the power of big industry did not ripen. Instead, big industry quickly took up his idea, and Diesel became very rich with his royalties.

Rudolf Diesel did not build the machine that bears his name. Rather he developed a theory of internal combustion, plus a few crude prototypes. However, none of the prototypes he worked on in his lifetime, worked especially well.

In 1893, German inventor Rudolph Diesel published a paper entitled “The Theory and Construction of a Rational Heat Engine,” which described an engine in which air is compressed by a piston to a very high pressure, causing a high temperature. Fuel is then injected and ignited by the compression temperature.

How is a diesel different from a spark ignition engine? In a spark ignition engine, air and fuel (gasoline) are mixed in the combustion chamber, compressed, and then ignited with a spark from the spark plug. In a diesel engine, air is compressed first, and then fuel is injected under very high pressures into the hot compressed air where it ignites immediately. For a number of reasons, particularly the much higher compression ratio, this is a more efficient way to get work output from the fuel. And because of the high pressures and forces which take place within the engine, diesels must be built much more robustly, which helps makes diesels last longer. So, most of the applications where diesels are applied are those in which fuel economy and long life are important to cost competitiveness in delivery of goods.

A spark combustion engine uses a throttle to control the amount of air coming into the engine, thus the amount of power that the engine will produce. There is no throttle in the diesel engine, thus there are no “pumping” losses as found in a spark ignition engine which struggles to suck air past a partially closed throttle at lower engine loads. Thus, when idling, a diesel engine uses perhaps only one fourth as much fuel as a spark ignition engine (that’s why you shouldn’t worry when you see a locomotive sitting with its engine running all night.)

Rudolph Diesel initially considered powdered coal and, later on, liquid fuels such as vegetable oil and petroleum as possible fuels. Powdered coal proved difficult to inject into the engine cylinder and eventually caused an explosion that destroyed the prototype engine. He built his first engine based on that theory the same year and, though it worked only sporadically, he patented it. Within a few years, his design became the standard of the world for that type of engine and his name was attached to it.

No other engine inventor's name is as closely tied to his engine as Rudolph Diesel's is. But Diesel worked hard to make it that way. Historian Linwood Bryant tells us that Diesel saw himself as a scientific genius and the James Watt of the late 19th century. He was vain, oversensitive, and not a little paranoid. He didn't win the hearts of other engine makers.

At Augsburg, on August 10, 1893, Diesel's prime model, a single 10-foot iron cylinder with a flywheel at its base, ran on its own power for the first time. During 1885 Diesel set up his first shop-laboratory in Paris and began his 13-year ordeal of creating his distinctive engine. Diesel spent two more years at improvements and on the last day of 1896 demonstrated another model with the spectacular, if theoretical, mechanical efficiency of 75.6 percent, in contrast to the then-prevailing efficiency of the steam engine of 10 percent or less.

Diesel built the first diesel engine in 1897 at the Augsburg Maschinenfabrik (now known as MAN). The single-cylinder engine was used to power stationary machinery. It weighed 4.4 tons (five tonnes) and produced 20 hp at 172 rpm. The engine operated at 26.2 percent efficiency, a very significant improvement on the 20 percent achieved by the best gasoline engines of the time. A number of industrialists expressed interest in acquiring licenses.

Although commercial manufacture begun at a snail's pace, by 1898 Diesel was a millionaire from franchise fees in great part international.

In March 1898, Scientific American published: “An advance as important as the introduction of the internal combustion motor has been made by Dr. Rudolph Diesel, of Munich. The experiments which led to the construction of the present successful machine began in 1882. In the ordinary gas or oil engine, the charge within the cylinder is ignited by a jet, hot tube or electric spark. In the Diesel motor the temperature of ignition is secured by the compression of pure air. Air is compressed to a pressure of up to 600 pounds to the square inch and the fuel, kerosene, is injected gradually into the cylinder and is burnt steadily during the stroke of the piston.”

When Dr. Rudolph Diesel demonstrated his engine at the world exhibition in Paris in 1900 he said two words that astonished the gathered engineers “peanut oil” The patented diesel engine ran on almost any fuel from petrol to vegetable oil! The engine was demonstrated at this exhibition running perfectly on straight peanut oil. Unfortunately Dr Diesel died before his vision of a vegetable oil powered engine was fully realized.

The seeds of the dispute, Bryant argues, were sown in Diesel's view of invention—the usual view that a device is first invented, then developed, and finally improved. Diesel left very clear records of what he actually did. There's no doubt that between 1890 and '93 he invented the engine using his knowledge of thermodynamics. The idea of burning fuel slowly, and at higher pressures, was certainly his.

There's also no doubt that he worked from 1893 to '97 at the Augsburg Machine-Works to develop a working engine. During this time Diesel faced problem after problem. To solve them he had to do a lot more theoretical work and more invention. In Diesel's view, he was still inventing the engine. People outside the process saw all this as development—the dirty work that anyone has to go through to make a good idea into workable hardware.

After 1897 Diesel figured he was done with his invention, and he turned to promoting it. But the engine was woefully unready for the market. Eleven more years of improvement and innovation were needed. Meanwhile, Diesel worked himself into a nervous breakdown promoting the not-yet-ready engine.

Diesel died under mysterious circumstances on September 29, 1913, vanishing during an overnight crossing of the English Channel on the mail steamer Dresden from Antwerp, Belgium to Harwich, Essex, England. His floating body was found ten days later.

Having already convinced the French navy that the only choice for submarine power was his engine and its associated low risk and edible fuel he was on his way to England by boat to try to do the same for the English navy when he disappeared.

Diesel's death might have been suicide, accidental, or an assassination.

When his body was found adrift in the English Channel a few days later, the English newspapers at the time suggested that French operatives trying to keep his engine out of the English submarine fleet had assassinated him. Other proponents of the assassination theory point out that shortly after Diesel's death, a diesel-powered German submarine fleet became the scourge of the seas.

Proponents of the suicide theory point to the fact that he was quite upset by criticisms of his work by other machinery manufacturers. In 1912, 20 years after the engine was conceived, four books were written about its development. Diesel wrote one. The other three were by people who were out to minimize his claims. He had irritated other engine designers by sneering at their work. In 1897, after he announced he had finished construction of the first commercially successful motor, he arrogantly asserted that few factories were good enough to build his engines—that second-string makers shouldn't even try. He failed to see that what made his engine viable in the marketplace was a lot of truly inventive thinking by a lot of good engineers. All Diesel's concern over public opinion made him an unhappy person. A person with that kind of talent should've known how to sit back and enjoy it.

The “whats” and “whys” of his demise will never be known, let alone the “whos”.

After Dr. Diesel's death the petroleum industry capitalized on his engine by labeling a by-product of petrol manufacture “diesel fuel” and modifying his engine to run on it. Diesel fuel was an invention that came much later than the diesel engine. Clean renewable vegetable oil was all but forgotten as a source of power.

A consortium of Alco, General Electric, and Ingersoll-Rand (AGEIR) first produced the 8835 (shown at left) demonstrator diesel-electric locomotive. Early into the demonstration trials it became apparent that the economic gains, reliability, and timing of prototype #8835 combined to create an acceptance of the Diesel-electric as a practical means of motive power. Demonstration service began June 9, 1924 with the New York Central RR in its West Side Yards and were concluded at the Alan Wood Steel Company of Conshohocken, Penn. on July 11, 1925. The success of these demonstrations prompted General Electric to design two versions of a Diesel-electric locomotive that would be entered into production. A 60-ton using one 300 hp Ingersoll-Rand engine and a 100-ton unit rated at 600 hp derived from two Ingersoll-Rand diesel power plants.

In June, 1925, the first production American-made diesel-electric locomotive—a 60-ton 300-hp Box Cab unit built on Alco Order No. S1484 and was assigned Alco builders plate No. 65979 and GE builders plate No. 9681 (shown right) . In keeping with General Electric's practice its builders plate No. 9681 was assigned to this unit while it was used in demonstrations at the Ingersoll-Rand plant in Phillipsburg, N.J. Number 9681 was completed and operating on the East Erie Test Track. It was delivered to Ingersoll-Rand under its own power during July 1925 where it replaced prototype No. 8835 as an in-house demonstrator. No. 8835 was retained for a short while as an interplant switch engine before being retired.

The construction of diesel-electric locomotives began with Alco issuing a Stock Order for the manufacture of one or more units of the same type. The “S” in AGEIR Order Numbers indicated that the mechanical portions were scheduled to be fabricated at Alco's Schenectady, N.Y. plant. Each completed assembly was then given an Alco builders number and shipped to General Electric's Erie, Penn. works where the Ingersoll-Rand diesel engines were being received. General Electric also issued a builders number for each of the units they were completing and Builders Plates were ordered for each locomotive and inscribed with both of the builders numbers as well as the names of each company of this consortium and general construction dates.

The Ingersoll-Rand four-cycle, vertical, six-cylinder diesel power plant with a 10” bore and a 12” stroke was rated at 600 rpm (550?) and 300 hp. Fuel was direct injected using a rotating distributing valve (something that Ingersoll-Rand was very proud of as the parts were machined to such close tolerances that they had to be lubricated prior to assembly). Lubrication was force-fed with the pressure pump and filter located in the crank case (an external distribution valve with dirt collector and fuel oil filter was also employed). The engine was of a water jacket design, including the head, and the water was cooled on the first eight 60-ton units by two roof-mounted fin tube convection type radiators with a total of 1,200 sq.ft. surface. The temperature was controlled by a thermostat and by-pass.

The generator for the three 60-ton units built on Alco Order No. S1484 was a General Electric 200 kW model TD-502 rated at 600 V and direct-connected to the engine. In turn a six kW, 60-V auxiliary generator (exciter) was direct connected. The shunt windings were separately excited and the series winding was differential compound. Voltage variation was rated at 200-750 V.

Beginning with Alco Order No. S1532, an improved General Electric Model T-D-6-6-200 Generator rated at 600 volts was used. Four General Electric Model HM-840 traction motors were installed (until Alco Order No. S1543, when Model GE292H motors were used). They had a nominal rating of 95 hp each at 600 V with two connected in parallel on each truck with series and parallel groupings.

Control of the early 300 hp locomotives was implemented by Model 2-C-173-A (Lemp system) controllers with electro-magnetic contactors and a reverser (one set of motorman controls located at each end of these AGEIR Box Cab units). A Type CP-26-600-V or Model CP-24-A12-600 compressor supplied 90 - 140 psi of pressure for the air brakes. One mechanically driven and/or one gasoline powered Mianus compressor furnished air for starting the diesel oil engine (Until Ingersoll-Rand locomotive No. 90 - Alco Builders No. 66752 - GE Builders No. 10132. At this time recharged storage batteries in conjunction with additional windings on the main generator cranked the power plant for starting).

Demonstrations of AGEIR 60-ton, 300 hp, No. 9681 were conducted in switching service at the Phillipsburg plant of Ingersoll-Rand beginning in July 1925. The CNJ Railroad had been one of the rail operations to participate in the earlier No. 8835 prototype demonstrator program and when they sent representatives to evaluate No. 9681 they were suitably impressed. The cab design was to their liking and the bulkheads separating the operator areas from the more centrally located main diesel engine section were amongst other improvements noted over the prototype. They purchased the unit and became the first owners of a production diesel-electric locomotive. No. 9681 retained its ALCO and GE builders numbers and the unit was painted “gloss black,” relettered (in “gold Gothic”) No. 1000 for the Central R.R. of New Jersey and delivered under its own power to the CNJ shops at Elizabeth Port, N.J. Car floats were a common practice in the New York City area and CNJ No. 1000 was delivered from Jersey City to the Bronx Terminal Yard by this means. No. 1000 entered service there on October 22, 1925 and spent its entire career of over three decades at this location. This unit was classified CNJ SD-3 and D3-O at various times. According to an account by N.W. James, a CNJ Director of Publicity, this AGEIR locomotive was overhauled and repainted with a “deep Sea Green” and the Jersey Central Lines “Miss Liberty” logo and lettering applied in “yellow” during 1947. In 1957 this historic Box Cab locomotive was retired and went on display at the Baltimore & Ohio Railroad Museum located in Baltimore, Md.

Today, there are two major locomotive manufacturers in the U.S., EMD and GE. The top of the line EMD is the SD90MAC and the top of the line GE is the AC6000. The SD90MAC uses the GM16V265H 16-cylinder, 6,300 hp engine. It measures 15 ft 8 in high by 80 ft 2 in long by 10 ft. 3 in. and weighs 415,000 lb. It produces 200,000 lbf starting tractive effort. The AC6000 (pictured below) uses GE’s GE7HDL 16-cylinder, 6,250 hp engine. It measures 15 ft 3 in high by 76 ft long and 9 ft. 11 in wide and weighs 425,000 lb. It also produces 200,000 lbf starting tractive effort.

NOTE: The Author is the editor of the National Railway Bulletin, the NRHS' premiere publication.