The EMD F7 was the builder's four entry in its line of freight service locomotives and proved to be one of the most successful ever built. The model debuted directly after the F3 in the late 1940s and with the Electro-Motive Division's success in the market up to that point, railroads quickly placed orders for the F7. Once again, the latest F series model proved to be very reliable and easy to maintain and before production ended on the F7 nearly 4,000 A and B units had been built more than outselling all other manufacturer's designs, combined. The F7 proved to be so reliable and useful for many lines that hundreds remained in regular freight service with their original owners through the 1970s and 1980s. Today, numerous EMD F7s remain preserved with some even still serving in freight service. The most famous set of F7s is the fleet owned by Class I Norfolk Southern Railway for use on its official business train.
The EMD F7 began production in February, 1949 directly after the F3. Internally, the model varied slightly from the F3 as it still carried GM's 16-cylinder model 567B prime mover, which could produce 1,500 horsepower. It did use a slightly updated generator, the model D12B, and traction motor, the model D27C that was first used on the "F5", which was technically a late model F3 (EMD did not distinguish the locomotive as an F5 itself). The new traction motor was meant to be more rugged and durable than the previous. However, it continued to offer the locomotive the same tractive effort as the earlier F3; 56,500 pounds starting and 40,000 pounds continuous. Using the same frame as the F3, F2, and FT the F7 was just over 50 feet in length and weighed 115 tons.
Once again railroads very much liked EMD's latest F model and many which had yet to fully dieselize did so after their F7 orders were completed (wartime restrictions had still held back some lines from either starting or completing their change over to diesel power). The model was easy to maintain and very reliable, and coupled with a matching 1,500 horsepower cabless B unit, doubled a train's power to 3,000 hp (in theory you could equip as many Fs to a single train as you wished so it simply came down to how much power you wanted on the head end). While intended for use in freight service, with their clean, streamlined design many EMD F7s also found their way into passenger service alongside E units and other F models (notably on the Santa Fe which sometimes featured Fs on trains as posh as the Super Chief and El Capitan). As with the F3, EMD slightly upgraded the F7's carbody during its production run, with most changes simply being to the grill.
The EMD F7 was the SD40-2 or GE AC4400CW of its day, the first true "common" diesel locomotive; thousands were built and could be found powering almost any train. When production had ended some 2,366 F7As and 1,483 F7Bs had been produced by December, 1954 just five years after the locomotive was first cataloged. This was also the first instance of the Electro-Motive Division's new General Motors Diesel subsidiary filling orders. Located in London, Ontario, the new plant made it much easier to sell locomotive to Canadian lines. In all, GMD sold 127 examples to the Canadian National, Canadian Pacific, and the Wabash for its line in southern Ontario between Detroit and Niagara Falls/Buffalo. The model was EMD's most successful in the F series as no other future design came even close to matching the F7's sales numbers.
The EMD F7's reliability and ruggedness can still be seen today as dozens remain preserved and in operation with a handful still pulling duty in active freight service, notably on shortline Grafton & Upton Railroad. Other places one can still find F7s in use include the Conway Scenic Railway, Reading Company Technical & Historical Society, Adirondack Scenic Railroad, Royal Gorge Railroad, Illinois Railway Museum, Potomac Eagle Scenic, and the Fillmore & Western. The most famous F7s are those which pull Norfolk Southern's business train and carry a livery inspired by predecessor Southern Railway. They include A units #4270 and #4271 as well as B units #4275 and #4276. To learn more about preserved F7s please click here. For technical data regarding the EMD F7 please click here. Also, for information about EMD's F series please refer to the chart below.
Electro-Motive Division F-Series Locomotives
|Model Type||Units Built||Date Built||Horsepower|
|FT||555 A Units/541 B Units||1939-1945||1,350|
|F3||1,111 A Units/696 B Units||1945-1949||1,500|
|F7||2,366 A Units/1,483 B Units||1949-1953||1,500|
|F9||100 A Units/154 B Units||1954-1960||1,750|
|F59PHI||Still In Production||1994-Present||3,200|
For more information on the EMD F series consider Mike Schafer’s Vintage Diesel Locomotives which looks at virtually all of the classic builders and models from Alco PAs to early EMD Geeps. If you’re interested in classic EMDs, or diesels in general, this book gives an excellent general history of both. You might want to also consider the book EMD Locomotives from author Brian Solomon. Solomon's book highlights the history of EMD from its earliest beginnings in the 1920s, to its phenomenal successes in the mid-20th century, and finally its decline into second spot behind General Electric in the late 20th century and eventual sale by General Motors in 2005. The book features 176 pages of EMD history and is filled with excellent photography and illustrations. If you're interested in perhaps purchasing either (or both) of these books please visit the links below which will take you to ordering information through Amazon.com, the trusted online shopping network.