EMD GP7 explained

EMD GP7
Powertype:Diesel-electric
Builder:General Motors Electro-Motive Division (EMD)
General Motors Diesel (GMD)
Buildmodel:GP7
Builddate:October 1949  - May 1954
Totalproduction:2,729 (plus 5 B units)
Aarwheels:B-B
Wheeldiameter:403NaN3
Minimumcurve:19° (3012NaN2 radius)
Wheelbase:402NaN2
Length:55feet
Width:10feet
Height:15feet
Locoweight:246000lb
Fuelcap:1600usgal[1]
Sandcap:18cuft
Coolantcap:230usgal
Lubecap:200usgal
Rpmrange:275–800
Generator:EMD D-12-B
Tractionmotors:(4) EMD D-27-B
Primemover:EMD 16-567B
Enginetype:V16 Two-stroke diesel
Aspiration:Roots blower
Displacement:9072cuin
Cylindercount:16
Cylindersize:NaNx
Poweroutput:1500hp
Maxspeed:650NaN0
Tractiveeffort:Starting: 650000NaN0 @25%
Continuous: 400000NaN0 @9.30NaN0
Locobrakes:Independent air
optional: dynamic brakes
Trainbrakes:Air, schedule 6-BL[2] or 6-BLC. Schedule 24-RL offered as optional.
Operator:See list
Operatorclass:Erie- MFSE-15a NYC- various P&E- 5612-5623 DRS-4c 5624-5625 DRS-4d P&LE- various NKP- ERS-15 PRR- ERS15 WAB- D15
Disposition:Some retired, some rebuilt into GP8s or GP10s, many in service

The EMD GP7 is a four-axle (B-B) diesel-electric locomotive built by General Motors Electro-Motive Division and General Motors Diesel between October 1949 and May 1954.[3]

The GP7 was the first EMD road locomotive to use a hood unit design instead of a car-body design. This proved to be more efficient than the car body design as the hood unit cost less to build, was cheaper and easier to maintain, and had much better front and rear visibility for switching.[4] Power was provided by an EMD 567B 16-cylinder engine which generated 15000NaN0.[5] The GP7 was offered both with and without control cabs, and those built without control cabs were called a GP7B. Five GP7B's were built between March and April 1953.

Of the 2,734 GP7's built, 2,620 were for American railroads (including 5 GP7B units built for the Atchison, Topeka and Santa Fe Railway), 112 were built for Canadian railroads, and 2 were built for Mexican railroads.

This was the first model in EMD's GP (General Purpose) series of locomotives. Concurrently, EMD offered a six-axle (C-C) SD (Special Duty) locomotive, the SD7. The GP7 was replaced by the GP9 model in GM-EMD's GP sequence.

History

ALCO, Fairbanks-Morse, and Baldwin had all introduced road switchers before EMD, whose first attempt at the road-switcher, the BL2 was unsuccessful in the market, selling only 58 units in the 14 months it was in production.[6] Its replacement, the GP7, swapped the truss-framed stressed car body for an un-stressed body on a frame made from flat, formed and rolled structural steel members and steel forgings welded into a single structure (a "weldment"), a basic design which is still being employed today. In heavy service, the GP7’s frame would bow and sag over time. This defect was corrected in later models.

The GP7 proved very popular, and EMD was barely able to meet demand, even after opening a second assembly plant at Cleveland, Ohio. Later, locomotives in EMD's GP-series came to be nicknamed ‘Geeps’. Many GP7s both high and short-hood can still be found in service today on shortline railroads and industrial operators. Although most Class 1 roads stopped using these locomotives by the 1980s some remain in rebuilt form on some major Class I railroads, as switcher locomotives.. The "GP" designation stood for "general purpose", while the "7" had no meaning other than matching the EMD F7 cab unit then in production.

Identification

The GP7, GP9 and GP18 locomotives share a similar car-body that evolved over time. Most GP7s had three sets of ventilation grills under the cab (where the GP9 only had one), and two pair of grills at the end of the long hood (where only the pair nearest the end was retained on the GP9). However, some late GP7s were built with car-bodies that were identical to early GP9s. Early GP7s had a solid skirt above the fuel tank, while late GP7s and early GP9s had access holes in the skirt (see photo of Illinois Terminal 1605, top left). Many railroads later removed most of the skirt to improve access and inspection.

Locomotives could be built with the engineer’s control stand installed for either the long hood, or the short hood designated as the front. Two control stands for either direction running was also an option, but one end would still be designated as the front for maintenance purposes. The GP7 was also available with or without dynamic brakes, and a steam generator installed in the short hood was also an option. In the latter case, the 1600usgal fuel tank was divided, with half for diesel fuel, and half for boiler water. One option available for locomotives without dynamic brakes, was to remove the two 22.5x[7] air reservoir tanks from under the frame, and replace them with four 12x[8] tanks that were installed on the roof of the locomotive, above the prime mover. These "torpedo tubes" as they were nicknamed, enabled the fuel and water tanks to be increased to each, although some railroads opted for roof-mounted air tanks and 2200usgal[9] fuel tanks on their freight ‘Geeps’.

Original buyers

Locomotives built by Electro-Motive Division, USA

OwnerQuantityNumbersNotes
Electro-Motive Division (demonstrator)15251350 hp GP7m; to Atchison, Topeka and Santa Fe 99, renumbered 2899[10] This unit was built with a 567BC engine.
3100 (ex-922), 200, 300to Chicago & North Western 1518–1520. 1518 first built, preserved and operating at Illinois Railway Museum
Aberdeen and Rockfish Railroad1205
Atchison, Topeka and Santa Fe2442650–28932855-2858 were built with 567C engines
52788A–2792AGP7B; 2788A-2789A, 2791A-2792A were built with 567C engines
Atlanta and St. Andrews Bay2501–502
Atlanta and West Point Rail Road5571–575
Atlantic and East Carolina Railway1501Renumbered 406.
Atlantic Coast Line Railroad154100-253
Baltimore and Ohio Railroad33720–731, 740–746, 910–922, 6405728-729; 740-746 were built with 567BC engines. Long-hood-forward
Bangor and Aroostook Railroad16560–575
Belt Railway of Chicago8470–477
Boston and Maine Railroad231555–1577
Butte, Anaconda and Pacific Railway3101–103
Central of Georgia Railway15106–107, 120–132
Central Railroad of New Jersey131520–1532
Atlantic Coast Line Railroad (Charleston and Western Carolina Railway)21200–220To Atlantic Coast Line 254-274.
Chesapeake and Ohio Railway1805700–5719, 5739–5797, 5800–59005720–5738 built by GMD
Chicago and Eastern Illinois Railroad30203–232
Chicago and North Western Railway1101521–1550, 1556–1559, 1562–1599, 1601–1603, 1625–1659
Chicago and North Western (Chicago, St. Paul, Minneapolis and Omaha Railway—"Omaha Road")11151–161
Chicago, Burlington and Quincy Railroad68200–267253-267 were built with 567BC engines
Chicago Great Western Railway2120–121
Chicago, Rock Island and Pacific Railroad113430–441, 1200–1237, 1250–1311, 1308 (2nd)1294-1299 were built with 567BC engines
Clinchfield Railroad17900–916
Colorado and Wyoming Railway2103–104Engines 103 & 104 are owned by the Pueblo Railway Foundation. Both locomotives are operable and used occasionally on Museum grounds .
Colorado Fuel and Iron2101–102Engine 102 is owned by the Pueblo Railway Foundation. The locomotive is operable and used occasionally on Museum grounds.
Atlantic Coast Line Railroad (Columbia, Newberry and Laurens Railroad)5100–104To Atlantic Coast Line 275-279.
Delaware, Lackawanna and Western Railroad20951–970To Erie Lackawanna, 1270-1284, 1405-1409.
Denver and Rio Grande Western Railroad145100–5113
Detroit and Toledo Shore Line Railroad1041–50
Detroit, Toledo and Ironton Railroad24950–973964-973 were built with 567BC engines
Erie Railroad521200–1246, 1400–1404To Erie Lackawanna, same numbers.
Florida East Coast Railway15607–621
Georgia and Florida Railroad6701–706
Georgia Railroad161021–10361035-1036 were built with 567BC engines
Great Northern Railway56600–655Long-hood-forward
Illinois Central Railroad488800–8801, 8850–8851, 8900–8911, 8950–89818800–8801, 8900–8911 had steam generators
Illinois Terminal Railroad61600–1605
Kansas City Southern Railway8155–162
Kansas City Southern (Louisiana and Arkansas Railway)5150–154
Kansas, Oklahoma and Gulf Railway9801–809
Louisville and Nashville Railroad61400–440, 500–514, 501–502 (2nd), 550–552
Maine Central Railroad19561–569, 571–580566-569 were built with 567BC engines
Meridian and Bigbee Railroad11Renumbered 101.
Midland Valley Railroad4151–154
Minneapolis, St. Paul and Sault Ste. Marie Railroad ("Soo Line")7375–378, 381–383
Missouri Pacific Railroad2084116–4194, 4197–43254116-4120, 4159-4165, 4203-4207, 4249-4253, 4284-4286, 4323-4324 owned by St. Louis, Brownsville and Mexico, 4121-4123, 4153-4158, 4197-4202, 4254-4255, 4287-4297, 4325 owned by International-Great Northern, 4290-4291, 4316-4320, 4325 were built with 567BC engines; 4292-4315, 4321-4324 were built with 567C engines.
Missouri–Kansas–Texas Railroad331501–1529, 1761–17641700s had steam generators. Renumbered 91–123
Nashville, Chattanooga and St. Louis Railway37700–731, 750–754700-705 built with EMD AAR TypeA trucks[11]
Ferrocarriles Nacionales de México (National Railways of Mexico)26600–6601
New York Central Railroad1695600–5611, 5626-5675, 5686-5712, 5738-5817Long-hood-forward
New York Central Railroad (Peoria and Eastern Railway)145612-5625Long-hood-forward
New York Central Railroad (Pittsburgh and Lake Erie Railroad)355676-5685, 5713-5737Long-hood-forward
New York, Chicago and St. Louis Railroad ("Nickel Plate Road")48400–447
Northern Pacific Railway20550–569to Burlington Northern Railroad 1624–1643;[12] 560-569 were built with 567BC engines
Pennsylvania Railroad668500–8512, 8545–8587, 8797–8806Long-hood-forward
Phelps Dodge Corporation71–2, 7–8, 27–29
Portland Terminal Company [Maine]11081
Reading Company44600–636, 660–666625-636 were built with 567BC engines. Long-hood-forward
Richmond, Fredericksburg and Potomac Railroad4101–104
Seaboard Air Line Railroad1231700–1822
Southern Railway572063–2077, 2156–2197
Southern Railway (Cincinnati, New Orleans and Texas Pacific Railway)116200–6205, 6240–6244
Southern Railway (Alabama Great Southern Railroad)56540–6544
Southern Railway (Georgia Southern and Florida Railway)48210–8213
St. Louis Southwestern Railway1320Renumbered 304.
St. Louis–San Francisco Railway129500–549, 555–632, 615 (2nd)
Tennessee, Alabama and Georgia Railway3707–709
Texas and Pacific Railway211110–1130
Texas Mexican Railway3850–852
Toledo, Peoria and Western Railway2102–103
Union Pacific Railroad30700–729720-729 were built with 567BC engines
United States Army201821–1840Built with EMD AAR TypeA trucks; 12 later served on Alaska RR and 11 were retrucked with AAR Type B road trucks
Wabash Railroad33450–452, 454–483453 built by GMD
Western Maryland Railway420–23
Western Pacific Railroad13701–713
Western Railway of Alabama6521–526
Totals 2617
5
GP7
GP7B

Locomotives built by General Motors Diesel, Canada

GP7 locomotives were built at GMD's London Ontario plant for domestic Canadian railway purchasers, and for some US railroads like the C&O and Wabash who owned and operated over trackage in Canada (specifically the southern Ontario area).

OwnerQuantityNumbersNotes
Algoma Central and Hudson Bay21150–170
Canadian National Railways254824, 7555–75784824 rebuilt October 1958 with parts from wrecked F3A. 7555-7578 renumbered to 4800-4823 mid-1957. Long-hood-forward
Canadian Pacific Railway178409–84258410-8411 originally built with steam generators
Chesapeake and Ohio Railway195720–5738C&O 5720-5729 resold to NYC as 5818-5827 for their Canadian operations
Quebec North Shore and Labrador Railway22100–101, 104–123
Toronto, Hamilton and Buffalo Railway771–77To CP (minus wrecked 71), all rebuilt as CP 1682-1687
Wabash Railroad1453Later to N&W 3453
Total 112

Rebuilds, modifications and conversions

There are five GP7s on A J Kristopan's EMD Serial number page that reused previous serial numbers: B&O 6405 (preserved), CRI&P 1308 (2nd), L&N 501 (2nd) and 502 (2nd), and SLSF 615 (2nd). These rebuilt units were rebuilt as new on new frames. Another rebuild by GMD is that CN 4824 was rebuilt as a GP7 with parts from an F3A in October 1958.

Over 100 GP7s and four of the GP7Bs were built with 567BC or 567C engines starting in March 1953 through May 1954. These are noted on the roster above.

Many railroads rebuilt their GP7s with low short hoods; some railroads went further in their rebuilding than others. Missouri Pacific Railroad upgraded their GP7s with 567BC engines (a B-block upgraded to C-block specs) and replaced the standard EMD 2-stack exhaust with a 4-stack "liberated" exhaust, raising their power output to 1600hp.[13]

Illinois Central Railroad rebuilt most of its GP7s with 567BC engines, 4-stack exhausts, paper air-intake filters, 26-L brakes (their original 6-BL brakes made them operationally incompatible with locomotives fitted with 24-RL brakes).[14] All but the first locomotive rebuilt had their front (short) hood reduced in height for improved crew visibility. The IC designated these rebuilt locomotives GP8. The IC acquired many second-hand units through Precision National Corporation (PNC), and then started offering their GP8/GP10 rebuilding services to other railroads through their Paducah Shops (note, a rebuilt "Paducah Geep" was designated a GP8 or GP10 depending on the power output of the rebuilt engine, not necessarily what it was rebuilt from).

In 1960 the Alaska Railroad purchased a dozen GP7Ls from the US Army and rebuilt eleven of them in 1965 with low short hoods for better visual clearance. One of the ten remaining Alaska GP7s was rebuilt by Morrison-Knudsen in 1976. The other nine units were rebuilt at Paducah Shops in 1976-1977.

Canadian Pacific Railway rebuilt their GP7 fleet in the early 1980's as GP7u units for yard service, including a chopped short hood, new numberboards and front cab windows, and upgrading the 567B prime movers with 645 power assemblies and to "BC" engine block specs (some upgraded with 567C engine blocks out of retired F-units).

Preservation

Numerous GP7s have been preserved on tourist lines and in museums. Holders include:

See also

References

EMD Product Reference Data Card dated January 1, 1959 has the 567BC and 567C engine data used in the as-built roster.

Notes and References

  1. Schrenk & Frey (1988) p.291
  2. IC Railroad 1969 diesel diagrams, pp.46–47
  3. Pinkepank, Jerry A. (1973) pp. 53
  4. Book: Schafer, Mike. Vintage diesel locomotives. 1998. Motorbooks International. 0-7603-0507-2. Osceola, WI. 37. 38738930.
  5. The History of EMD Diesel Engines
  6. Pinkepank, Jerry A. (1973) p. 51
  7. NP Railway diesel diagram, NP 550–551
  8. NP Railway diesel diagram, NP 557–558
  9. Schrenk & Frey (1988). p.159
  10. Pinkepank, Jerry A. (1973) p.56
  11. Web site: L&N 494. rrpicturearchives.net. 2019-06-14.
  12. Schren & Frey (1988). p.162
  13. Marre & Pinkepank (1988). p.192
  14. Marre & Pinkepank (1988). p.183