A Missouri Pacific E3 locomotive. Note the special design for the MP with double portholes.

(University of Southern California Library/California Historical Society, CC BY 3.0 <https://creativecommons.org/licenses/by/3.0>, via Wikimedia Commons)



The EMC E3 is a 2,000 horsepower (1,500 kW), A1A-A1A passenger train locomotive that was manufactured by Electro-Motive Corporation of La Grange, Illinois. The EMC demonstrator No. 822 was released from La Grange for test on September 12, 1938. The cab version, or E3A, was manufactured from September 1938 to June 1940, and 17 were produced. The booster version, or E3B, was manufactured in March 1939 and September 1939, and 2 were produced. The 2,000 hp (1,500 kW) was achieved by putting two 1,000 horsepower (750 kW), 12-cylinder, model 567 engines in the engine compartment. Each engine drove its own electrical generator to power the traction motors. The E3 was the fourth model in a long line of passenger diesels of similar design known as EMD E-units.

Compared with passenger locomotives made later by EMD, the noses of the E3, E4, E5, and E6 cab units had pronounced slants when viewed from the side. Therefore, these four models have been nicknamed "slant nose" units. Later E models had the more vertical "bulldog nose" of the F series. E3 demonstrator 822 was built with a nose identical to earlier EA and E1A units, but later locomotives in the series featured an elevated headlamp mounted in a nacelle, distinct from the flush profile mounting of the earlier units. 822 was modified in a similar fashion prior to delivery to the Kansas City Southern Railway.


Engine and powertrain

The E3 introduced a 12-cylinder version of the 567 series Diesel engine, with two being used for a total of 2,000 hp at 800 rpm. Earlier E-units had used two Winton 201A prime movers, but that engine was eventually proven to be ill-suited to railroad use and was unreliable. The 567, which was specifically designed for railroad motive power applications, is a mechanically-aspirated, two-stroke 45-degree V-type with 567 cubic inches (9,290 cm3; 9.29 L) displacement per cylinder, and remained in production until 1966. Two direct current generators, one per engine, provide power to four traction motors, two on each truck, in an A1A-A1A arrangement. This truck design was used on all E-units and on MP 7100, CB&Q 9908, and Rock Island EB6 power cars. EMC/EMD has built all of its major components since 1939.


Original owners

A Units

Railroad Quantity Road numbers Notes
Electro-Motive Corporation (Demonstrator) 1 822 to Kansas City Southern Railway No. 1
Atlantic Coast Line Railroad 2 500, 501 500 was wrecked in Fleming, GA in 1953 and rebuilt by EMD as an E8A. 501 was wrecked before delivery and rebuilt by EMC as an E6A.The 501 is preserved at the NCTM.
Atchison, Topeka and Santa Fe Railway 1 11
Chicago and North Western Railway 4 5001A, 5001B, 5002A, 5002B Initially used in A-A back-to-back pairs on the Twin Cities 400.
Chicago, Rock Island and Pacific Railroad 2 625, 626
Florida East Coast Railroad 2 1001, 1002
Kansas City Southern Railway 2 2, 3 Used initially for the Southern Belle passenger train.
Missouri Pacific Railroad 2 7000, 7001 Built with two sets of double round portholes on each side.
Union Pacific Railroad 1 LA-5 Built with two sets of triple round portholes, similar to the UP EMC E2; later modified and renumbered.
Total 17

B Units

Railroad Quantity Road numbers Notes
Atchison, Topeka and Santa Fe Railway 1 11A
Union Pacific Railroad 1 LA-6 matched with A-unit (see notes for UP LA-5)
Total 2

Atlantic Coast Line E6A 501 with the East Coast Champion at AF Tower, Alexandria, VA in August 1964. 

501 was an EMC E3 wrecked before delivery in 1939 and rebuilt by EMC as an E6A. The 501 is preserved at the NCTM, Spencer, NC.

(Roger Puta, Courtesy Marty Bernard, railfan 44, Public domain, via Wikimedia Commons)


EMC E3 Type and origin

Power type: Diesel-electric
Builder: Electro-Motive Corporation (EMC)
Model: E3
Build date: September 1938 – June 1940
Total produced: 17 A units, 2 B units
​• AAR A1A-A1A
Gauge 4 ft: 8+1⁄2 in (1,435 mm)
Trucks: EMC Blomberg A-1-A passenger
Wheel diameter: 36 in (914 mm)
Minimum curve: 21° (274.37 ft or 83.63 m radius)
Wheelbase: 57 ft 1 in (17.40 m)
Length: 70 ft 4 in (21.44 m) over coupler pulling faces
Width: 10 ft 7 in (3.23 m)
Height: 15 ft 10 in (4.83 m)
Locomotive weight: 308,400 lb (139,900 kg)
Fuel capacity: 1,200 US gal (1,000 imp gal; 4,500 L)
Prime mover: EMC 567 x 2
RPM range: 800 max
Engine type: V12 Two-stroke diesel x 2
Aspiration: Roots blower
Displacement: 6,804 cu in (111.50 L) each
Generator: EMC D-4 x 2
Traction motors: EMC D-7 x 4
Cylinders: 12 x 2
Performance figures
Maximum speed: 116 mph (187 km/h)
Power output: 2,000 hp (1,490 kW) total
Tractive effort Starting: 56,500 lbf (25,628 kgf) @25%
Tractive effort Continuous: 31,000 lbf (14,061 kgf) @11 mph (18 km/h)

Atlantic Coast Line Railway, Seaboard Coast Line Railroad
Disposition: One preserved at the North Carolina Transportation Museum