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EMD "FP7" Locomotives

Last revised: July 24, 2023

By: Adam Burns

The incredible success of Electro-Motive's F7, and earlier F3, led the builder to catalog a variant sporting a larger steam generator for passenger service, the FP7.  Internally and visually, the locomotive was nearly identical to its counterpart save for its increased length.

Interestingly, despite already offering a standalone passenger series, some railroads found the B-B trucked F units more to their liking in passenger service as the locomotives offered better tractive effort in mountainous territory.  The E models' A1A-A1A trucks, with an unpowered center axle, had trouble on stiff grades.

Surprisingly, for a variant, the FP7 sold quite well with nearly 400 examples manufactured (including those constructed by subsidiary General Motors Diesel for Canadian lines). Today, numerous FP7s remain preserved and in operation around the country.

Notable units include a pair of demonstrator units (#7001 and #9051), Clinchfield #200 at the West Virginia Central, Southern Railway #6133 at the North Carolina Transportation Museum, and Southern Railway #6141 and #6138 which pull RJ Corman's My Old Kentucky Dinner Train.


6902172616178269838970938.jpgMilwaukee Road FP7 #103-C has one of Union Pacific's "City" streamliners at Davis Junction, Illinois in April, 1969. American-Rails.com collection.


The FP7 entered production in June, 1949 when Rock Island #402 rolled out of EMD's McCook plant that month.  As the builder ramped up production of its "E" series catalog, some roads, like the previously-mentioned AT&SF and SP, realized the locomotives' A1A-A1A trucks provided relatively poor traction in mountainous environments.

In his book, "Southern Pacific Historic Diesels, Vol. 3," author Joseph A. Strapac notes the Southern Pacific considered the E7, for example, "...a frail device, better suited to the water-level New York Central than the harsh operating environment of the far West.  Far too often, SP's combination of heavy trains and rugged profiles forced dispatchers to assign helpers to E7 consists."

To remedy this, SP took the somewhat unique approach of purchasing a large fleet of PAs, especially the later PA-2, which sported the more rugged and robust GE-built 752 traction motors.  The Santa Fe took a somewhat different approach, deciding to equip its top trains with the sure-footed F3 and F7.

With their B-B trucks, the Fs placed their full weight on the rails.  As a result, the FP7 could offer tractive efforts between 29,500 to 40,000 lbs (depending on gear settings) while the best an E7 could provide was 27,000 lbs at the lowest gear setting.

EMD already cataloged the F2, F3, F7, and later F9 with optional steam generators.  However, the engine compartment did not have sufficient room for both the generator and needed water supply.  To get around this, Louis A. Marre notes in his book, "Diesel Locomotives: The First 50 Years," EMD placed water tanks under the frames of these models.  In addition, the steam generator exhaust stack was located at the rear of the locomotive's roof.

In the Santa Fe's case, it attempted to provide amble water supply by placing a generator in the F3's "A" unit and the water tank in the accompanying B unit.  Such a maneuver did work but always required at least two units in every train consist, thus increasing operating costs.

The FP7 solved all of these issues.  In his book, "Electro-Motive: E-Units and F-Units," author Brian Solomon notes the model provided a 970-gallon water tank for the steam generator with a total water capacity of 1,750 gallons, nearly twice as much as a comparable F3.

This allowed the locomotive to operate much longer between necessary water stops.  It also carried an added benefit of doubling in freight assignments; such redundancy was always cherished by railroads. 

92803942375723752639860943077.jpgKaty FP7 #81-C is seen here stopped at Parsons, Kansas with the company business train on October 4, 1968. Mac Owen photo. American-Rails.com collection.

To house the steam generator and water tank inside the cab, the FP7 was 54' 8" in length, four feet longer than a typical F7.  In his book, "Diesel Locomotive Cyclopedia - Volume 2," author Bob Hayden notes the stretched out carbody can be seen between the first porthole (nearest the cab) and first set of louvers.

Aside from its steam generator components, the FP7 was nearly identical to the F7.  It featured EMD's 16-cylinder, model 567B prime mover - that could produce 1,500 horsepower - and carried the company's D27C traction motors, which offered as much as 40,000 pounds of continuous tractive effort.

It did, however, use a slightly upgraded main generator, the model D12D.  Since the FP7 already housed all of the components needed for passenger service, there was little need to offer a cabless "B" variant.

In comparison to the FT, F3, and F7's success, the FP7's sales numbers appear low; only 379 were produced by the time production ended on the model in late 1953.

However, as a variant, it solved a specific and very important need for railroads either after greater tractive effort in passenger assignments or wanting a dual-service locomotive. 

Data Sheet and Specifications

Entered Production6/1949 (Rock Island #402)
Years Produced6/1949 - 12/1953
Engine BuilderGM
Length54' 8"
Height (Top Of Rail To Top Of Cab Horn)15' 0"
Width10' 8"
Weight258,000 Lbs
Fuel Capacity1,200 Gallons
Air CompressorGardner-Denver
Air Compressor ModelWBO
Air Brake ManufacturerWestinghouse
Air Brake Schedule24RL
Truck TypeBlomberg
Truck Wheelbase9'
Wheel Size40"
Traction MotorsD27C (4), GM
Primary GeneratorD12D, GM
Auxiliary GeneratorDelco (A8102)
MU (Multiple-Unit)Yes
Dynamic BrakesYes
Gear Ratio62:15, 61:16, 60:17, 59:18, 58:19
Tractive Effort (Continuous, at 9.3 mph)40,000 lbs; 37,000 lbs; 34,000 lbs; 32,000 lbs; 29,500 lbs
Top Speed65 mph, 71 mph, 77 mph, 83 mph, 89 mph

* Despite intended use in general passenger service, steam generators were still optional in the FP7.  They were produced by Vapor Clarkson; model OK4625 (2,000 Lbs/Hr).

Production Roster

Total Built = 299

Owner Road Number(s) Serial Number(s) Order Number Date Built
Chicago & Eastern Illinois 1600-1609 7535-7544 E1076 08-09/49
Georgia Railroad 1002 7605 E1091 11/1949
Western Railway of Alabama 502-503 8018-8019 E1131 11/1949
Atlanta & West Point 551-552 8020-8021 E1176 8/1949
Georgia Railroad 1003 8322 E1091 11/1949
Rock Island 402-411 8623-8632 E1199 6/1949-7/1949
Georgia Railroad 1004 8870 3003 2/1950
Western Pacific 804A, 804C-805A, 805C 9002-9005 6043 1/1950
Milwaukee Road 90A, 90C-95A, 90C 10323-10334 3050 6/1950-7/1950
Milwaukee Road 96A, 96C-97A, 97C 10361-10364 3073 1/1951
Soo Line (Minneapolis, St Paul & Sault Ste Marie) 501A 10897 6134 1/1950
Electro-Motive (Demonstrator) 7001 (became Soo Line/Wisconsin Central #2500A) 11012 6061 (sold on 6136) 11/1949
Electro-Motive (Demonstrator) 9051 (became Soo Line #500A) 11015 6062 (sold on 6136) 11/1949
Reading 900-905 11387-11392 6091 5/1950-6/1950
Southern (Cincinnati, New Orleans & Texas Pacific) 6130-6139 11507-11516 6113 4/1950-5/1950
St. Louis Southwestern Railway (Cotton Belt) 330 11628 3056 4/1950
St. Louis-San Francisco Railway (Frisco) 5040-5045 11637-11642 6127 12/1950
Soo Line (Wisconsin Central) 2501A 12211 6137 6/1950
Southern (Cincinnati, New Orleans & Texas Pacific) 6140-6149 12336-12345 6144 10/1950-12/1950
Pennsylvania 9832A-9866A 12410-12444 3066 4/1952-8/1952
Richmond, Fredericksburg & Potomac 1201-1203 12908-12910 6171 11/1950
Atlantic Coast Line 850-859 13051-13060 6179 4/1951
Louisville & Nashville 663-668 13430-13435 3075 12/1951-1/1952
Chicago Great Western 116A, 116C 13559-13560 6222 12/1950
Atlanta & West Point 553-554 13569-13570 6202 2/1951
Louisville & Nashville 600-621 13834-13855 6216 1/1951-3/1951
Atlantic Coast Line 860-869 13971-13980 6179 4/1951-5/1951
Soo Line 502A-503A 13997-13998 3080 3/1951
St Louis-San Francisco Railway (Frisco) 5046-5051 14087-14092 6235 2/1951
Louisville & Nashville 622-634 14465-14477 6271 6/1951-8/1951
Louisville & Nashville 669-672 14588-14591 3075 1/1952
Clinchfield 200 14804 6310 2/1952
Missouri-Kansas-Texas (Katy) 121A, 121C-124A, 124C 14805-14812 6318 1/1952-2/1952
Atlantic Coast Line 870-889 14839-14858 3083 8/1951-10/1951
Milwaukee Road 98A, 98C-103A, 103C 15227-15238 3111 10/1951-12/1951
Florida East Coast 571-575 15568-15572 3088 12/1951
Pennsylvania 9867A-9871A 15643-15647 3066 8/1952
Northern Pacific 6600-6601 15681-15682 3135 2/1952
Chesapeake & Ohio 8000-8013 16050-16063 3096 2/1952-4/1952
Soo Line 504-505 16472-16473 3136 9/1952
Reading 906-907 16681-16682 3150 9/1952
Milwaukee Road 104A, 104C-105A, 105C 16944-16947 3130 9/1952
Union Pacific 911-912 17231-17232 6444 4/1952
Atlantic Coast Line 890-893 17256-17259 6445 8/1952-9/1952
Chesapeake & Ohio 8014-8015 17490-17491 3163 12/1952
Southern Pacific 6446-6461 18130-18145 3160 2/1953-3/1953
Alaska Railroad 1510-1514 (Evens) 19064-19066 3169 12/1953


Total Built = 2

Owner Road Number Serial Number Order Number Completion Date Heritage
Chicago Great Western 116C 13560 8000 10/1951 Original #116C built in 12/1950
Chicago & Eastern Illinois 1609 7544 8003 1/1952 Original #1609 built in 9/1949

General Motors Diesel (GMD)

Total Built = 57

Owner Road Number(s) Serial Number(s) Order Number Date Built
Canadian Pacific 4028-4037 A100-A109 C100 9/1950-10/1950
Ontario Northland 1500-1505 A174-A179 C111 3/1951-4/1951
Canadian Pacific 4038-4041 A242-A245 C116 9/1951-10/1951
Canadian Pacific 4058-4063 A306-A311 C132 1/1952-4/1952
Canadian Pacific 4066-4075 A367-A376 C147 8/1952-10/1952
Ontario Northland 1506-1513 A377-A384 C121 6/1952
Canadian Pacific 4099-4103 A520-A524 C165 4/1953-6/1953
Ontario Northland 1514-1521 A525-A532 C166 7/1953-10/1953


Total Built = 21

Owner Road Number(s) Serial Number(s) Order Number Date Built
Secretaría de Comunicaciones y Obras Públicas (Mexico) 9888-9889 23035-23036 E1313 9/1949
Ferrocarriles Nacionales de México 10888-10896 6300-6308 6052 12/1949-1/1950
Ferrocarriles Nacionales de México 11011 6309 6052 1/1950
Ferrocarriles Nacionales de México 15158-15164 6328A-6334A 6335 11/1951
Arabian-American Oil Company (Saudi Arabia) 17497-17498 1006-1007 7019 1/1953

8346923095276723768340797986298908.jpgSt. Louis-San Francisco ("Frisco") FP7 #40 (built as #5040) is seen here at the engine terminal in Springfield, Missouri, circa 1968. American-Rails.com collection.


A little more than two dozen railroads bought the FP7 along with foreign lines Arabian American Oil Company and Ferrocarriles Nacionales de México.  For General Motors Diesel, it sold another 57 to the Canadian Pacific and Ontario Northland Railway.

Interestingly today, numerous FP7s remain preserved, many still operable in excursion service.  Tourist railroads like the West Virginia Central, Stone Mountain Railroad, and Verde Canyon Railroad all use FP7s.

Additionally, R.J. Corman operate a few on its dinner train and the Canadian Pacific uses a fleet to power the luxurious Royal Canadian Pacific train. 


  • Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.
  • Hayden, Bob. Diesel Locomotives: Cyclopedia, Volume 2 (Model Railroader). Milwaukee: Kalmbach Publishing Company, 1980.
  • Marre, Louis A. Diesel Locomotives: The First 50 Years, A Guide To Diesels Built Before 1972.  Milwaukee: Kalmbach Publishing Company, 1995.
  • Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.
  • Solomon, Brian.  EMD Locomotives.  Minneapolis: MBI Publishing Company, 2006.
  • Solomon, Brian.  Electro-Motive E-Units and F-Units: The Illustrated History of North America's Favorite Locomotives.  Minneapolis:  Voyageur Press, 2011.

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