Thank You Mark Bremer for “The Dilworth Story”- Pioneer Developer of the Diesel Locomotive

This charming little book arrived totally unexpectedly in the mail the other day, sent by Scott Bremer, who has to be a CC reader. (Update: it was actually CC Commentator Mark Bremer’s book, but he had lent it to his brother Scott, who sent it to me). But I don’t know who he is online, so I’m going to thank him here, and take the opportunity to do a review of The Dilworth Story. It was apparently commissioned by GM’s Electro-Motive Division in 1954, not long after his retirement. Richard Dilworth was one of the key individuals in the development of the diesel-electric locomotive, although his now-unfashionable modesty compelled him to point out there were many others who played important roles too, with this line he quoted from Bobby Burns: “My mother was a canteen lassie. Anyone of a troop of dragoons was my father”.

That and the fact that Dilworth attended exactly one half day of school in his whole life (seriously), grew up in the wild North West of the late 1800s, and left home at the age of twelve to make his way in the world and become a completely self-taught engineer. One who was able to solve highly complex problems that other trained engineers sometimes couldn’t, probably precisely because he wasn’t school-educated, and for whom “thinking outside of the box” was all he ever knew. It all makes for a great read.

As you know, trains are right up there with cars on my interest level, and the development of the diesel electric locomotive, which utterly transformed motive power in the US (and many other countries) has long been a particular interest. My main post on the subject at CC is here, covering the development of the diesel-electric streamliners almost perfectly congruently with Dilworth’s career, but his name never comes up once, as all the source I used never singled him out.

Having somehow faked his way into becoming something of a machinist and then an electrician, Dilworth found himself at GE’s Schenectady, NY plant in 1910, when it started building its first gasoline-electric railcars (note: the pictures above are not from the book, but gives an idea of the state of the art then. Actually, this Hall-Scott rail car and many others were mechanically driven with clutches and gears, and GE’s efforts at a gas-electric railcar was specifically conceived to overcome the shortcomings of mechanical drive).  This was a new thing altogether for Dilworth, but almost instantly he saw the potential and “I swore a terrible oath that I was going to stay with that kind of motive power until it was pulling the Twentieth Century Limited”. And that’s exactly how it turned out. But it was hardly a straight line to that, as the whole rail car business went through a long dormancy after its initial burst of popularity.

His first job there (aged 25) was to design and build the actual gasoline engine for this first GE railcar. That was a bit of a challenge, but he took it on and it worked, but not before he quickly ditched a correspondence school course on gasoline motors. It was from 1905, and the state of the art had already changed radically since then.

By 1913, that first boom was over, because the railroad engineers, who were so deeply steeped in steam, couldn’t get the hang of running and maintaining a gas engine. Many of the early rail cars were mothballed; it was just too exotic for them. Dilworth worked on other GE programs, and started working on diesel engines for stationary use, as they were too heavy and had too little output to be useful in a motive capacity.

In 1923, the gasoline rail car suddenly came roaring back. Due to rapidly increasing competition from cars, buses and trucks, branch lines and even secondary rail lines were hurting badly, and the rail car offered the only economical way to keep service going. And now there was a new generation of young motive power guys at the railroads who all had cars, and understood their ways.

Dilworth was called back to develop a new car at GE, and looked around for a suitable company or resources to work with, and found Hal Hamilton, at a small firm called Electro-Motive. Dilworth really liked what he saw, and within a year jumped ships to E-M, and never looked back.

Their first product was a relatively large and powerful 57′ rail car (above) unlike the competition, which was mostly trying to adapt trucks and buses to rails (“doodle bugs”). The E-M rail car was powerful enough to even pull another car, which greatly enhanced its utility and endeared it to the railroads.

So much so that the railroads wanted ever bigger and more powerful rail cars. The problem was that any engine over some 800hp was difficult to fit, and the price of gasoline jumped dramatically during the Roaring Twenties. So Dilworth went to work with the Winton Engine Company to develop a distillate-burning engine, a sit cost 3¢ versus 15¢. Distillates were a wide range of secondary byproducts from the distilling process other than heavy oil (diesel) or gasoline. It required special carburetors, one for each cylinder, and four spark plugs per cylinder to ignite the stuff.

The final development of these distillate engines went into a quite unique rail set, the 900hp V12 M-190 for Santa Fe. Because of all that unprecedented power, it needed four electric motors, so Dilworth came up with an elegant solution, by articulating its two driven trucks with an attached baggage car. And he pioneered the use of truck-mounted brake cylinders, despite massive resistance. Santa Fe was sure this first articulated unit wouldn’t stay on the rails above 35mph, but it actually rode better than standard rail cars, and was the prototype of many articulated units to come. It was designed to pull up to 5 passenger cars, but in its later life after it was dieselized, it pulled up to 15 on fairly flat Kansas terrain.

A 600hp version of the same engine went into the first lightweight streamliner, the UP M-10000, which quickly proved itself highly capable, and was able to cruise at 90mph and hit 110.

In 1930, GM bought both Winton and E-M, and the famous GM Kettering Labs set itself to designing a new diesel engine. To achieve the goals of unprecedented power-to-weight ratios, Charles Kettering adopted the two-stroke cycle. Originally developed for Navy subs, the first two engines, the Winton 201, were shown at the 1933 Chicago Century of Progress Fair, where they were not only displayed but generated power. My post on the birth of that legendary engine is here.  The same basic concept would be scaled down into two smaller families, the 184, for smaller subs and other marine use, and the -71 series, for trucks, buses, even smaller marine use and also military applications.


Ralph Budd, president of the Burlington RR, wanted a streamliner too, but he took the gamble of using the brand new and untried Winton 201 diesel in his Pioneer Zephyr (right). It was a success, but engineers had to ride along in those early days and be prepared to make repairs on the go. The further development of the Streamliners is here, but in essence the first generation of them were increasingly longer and more powerful versions of these fully articulated units, meaning they were coupled together essentially permanently. That would soon prove to be a very limiting approach. Diesels were more economical, but the railroads wanted them to pull their existing fleet of cars too. And the flexibility of stand-alone locomotives.

Dilworth came up with the solution in 1934, one that seems obvious now, but was wholly untried at the time. It had to be a locomotive that could equal the best high-speed passenger steam locomotives at the time, which could generate up to 5,000 hp. he calculated that a diesel-electric would need less, about 3,600hp, to equal them due to its inherently more consistent output and tractive effort. The trick was to get GM to appropriate the money to develop and build them. They did.

So he installed two of the 900hp V12 Winton 201 diesels and four motors into what he called a “box car”. And then join two of them together, to make the first high-power high-speed diesel locomotive. It was a highly pragmatic solution, but that was the hallmark of Dilworth.

The first, a single demonstrator #50, went to the B&O (top). And the first co-joined set went to the Santa Fe (bottom), where they were face lifted once they were put in service hauling the Super Chief.

They acquitted themselves superbly, and soon begat a long line of EMD passenger locomotives which initiated the diesel revolution and dominated the field.

But the inherent advantages of diesels was not lost on the railroads’ freight motive divisions, and the next challenge for Dilworth was just that. It required a somewhat different approach, with smaller single V16 1350hp engine, and with four axles, for greater tractive effort, essential for starting a mile-long freight train from a standing start. The result was the FT from 1939, a 5400 hp A-B-B-A unit, of which the A and B unit were permanently coupled. Dilworth quickly saw that as one of the biggest “boners” he had made, and subsequent versions (F3, etc.) were all individual units so they could be used in any number of variations depending on the motive power need.

Dilworth’s last major project was the GP7, originally designed to be a cheaper multi-purpose “road switcher” for secondary and branch lines, but its lower cost, easy service accessibility and pragmatic design quickly made it the new work horse of the freight lines, and is of course the first of a very long line of EMD freight locomotives.

This started out as just a thanks to Scott Bremer, but it ended up a little more than that. But Richard Dilworth deserves his 15 minutes of fame here at CC, and I’m honored to give it to him. I can’t quite convey the actual feel and tone of the book, which manages to capture Dilworth’s colorful personality, so if you can find a copy yourselves, I highly recommend it.