Saint Paul, Minneapolis & Manitoba(GN / Montana Central / Eastern Railway of Minnesota / Great Northern 4-8-0 "Mastodon" Type Locomotives

Class Details by Steve Llanso

Class G-1 (Locobase 8565)

Data from M Grille & MH Falconnette, Les Chemins de Fer a L'Exposition de Chicago, (Paris, France: E Bernard et Cie, 1894), p 44-47, supplemented by GN 1916 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection. Brooks builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004. Works numbers werew 1972-1981in October 1891, 1998-2000 in November, 2001-2002 in December and a exhibition engine for the Columbian Exposition in Chicago as works number 2261 in March 1893.

This class was originally delivered with 20" x 24" cylinders. Even with the longer stroke, the cylinder proportions were still at odds with most Twelve-wheelers. Like virtually all Great Northern locomotives, however, these had Belpaire fireboxes.

The StPM&M was organized in May 1879 as an amalgamation of the Saint Paul & Pacific, Morehead & Barnesville, and the Red River Valley. At that point, the Great Northern leased the railroad (extending it in 1890), but the StPM&M held on to its separate identity until the line was sold to the GN in 1907.

When these fifteen Twelve-wheelers arrived, the StPM&M comprised 2,775 miles. At the time of its sale, the railroad encompassed 3,879 miles of track.

Class G-2 (Locobase 8847)

Data from GN 1916 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. Brooks produced these in June (2973-2975), July (2982-2990), August (3045-3048), and September (3049-3052).

Like all GN 4-8-0s, the G-2s had small drivers and Belpaire fireboxes. Very shortly after the ERofM had taken delivery of this class, the railroad was absorbed by the Great Northern. Except for the 701, which was converted to a 2-8-0 and redesignated F-3, these Twelve-wheelers remained essentially unchanged and had 30-year careers.

Class G-3 (Locobase 8816)

Data from GN 4 1946 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

This large order of Twelve-wheelers came at the height of that wheel arrangement's popularity. As with most GN locomotives, this design had the signature Belpaire firebox. The small drivers meant these would always perform in slow-freight duties, but they were serviceable enough for 20 to have been retained through World War II. Some of the class had bigger tenders carrying 15 tons of coal.

At least one was superheated; see Locobase 8817.

Class G-3-S (Locobase 8817)

Data from GN 4 1946 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Among the 50-odd G-3 Twelve-wheelers were a couple that were later superheated. The H & D superheater is a rarity - notice the small bore of the flues. The gain in effective steam was needed for the railroad increased the cylinder diameter by 4 1/2", while reducing boiler pressure to an anemic 160 psi. 722 had 189 2" tubes as shown while 734 had 185 and a total evaporative heating surface of 1,980 sq ft.

Class G-4 (Locobase 8818)

Data from GN 4 1946 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

The large Rogers order for 50 Twelve-wheelers in 1899-1900 (see Locobase 8816) was followed by this decade from the Dunkirk, New York builder who had made a specialty out of large engines in this wheel arrangement. The boiler certainly was large and must have taxed the relatively small grate in the Belpaire firebox.

Class G-5 (Locobase 191)

Data from 1899 Brooks catalogue and from McShane (1899).

Brooks builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004. Works numbers were 2866-28677 in December 1897 and 2999-3004 in July 1898.

Designed by JO Pattee, superintendent of Motive Power for the Great Northern. Not a very attractive engine because of its high Improved Belpaire (aka Player-Belpaire) boiler with its inelegant square-shouldered firebox. (The firebox contained 26 sq ft of arch pipes.) Still, the 16-in diameter piston valves are worthy of notice, as large, McShane noted, as the pistons of many locomotives then in service. Indeed, much about the engine, including a 34-in piston stroke and other "brobdignagian" dimensions, made it a conversation piece of the time.

MC #103 was Brooks's 3,000th engine. When the Great Northern absorbed the Montana Central in 1902, this class was renumbered 800-807. One -- 806 -- was turned into a 2-8-0 in 1905 and redesignated F-10. All were scrapped in the late 1920s - early 1930s.

Two later classes -- G-3 (50 from Rogers) and G-4 (10 from Brooks for the Eastern Railway of Minnesota) were similar, but had 19x32" cylinders.


Specifications by Steve Llanso
ClassG-1G-2G-3G-3-SG-4G-5
Locobase ID8565 8847 8816 8817 8818 191
RailroadSaint Paul, Minneapolis & Manitoba(GN)Eastern Railway of Minnesota (GN)Great Northern (GN)Great Northern (GN)Great Northern (GN)Montana Central (GN)
CountryUSAUSAUSAUSAUSAUSA
Whyte4-8-04-8-04-8-04-8-04-8-04-8-0
Road Numbers400-415700-719720-769722770-779100-107 / 800-807
GaugeStdStdStdStdStdStd
BuilderBrooksBrooksRogersGNBrooksBrooks
Year18911898189919001897
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase15.50'15.33'15.58'15.58'15.33'15.83'
Engine Wheelbase25.25'26.17'23.08'23.08'22.83'26.67'
Ratio of driving wheelbase to overall engine wheebase 0.61 0.59 0.68 0.68 0.67 0.59
Overall Wheelbase (engine & tender)52.08'53.83'52.60'54.08'53.83'54.25'
Axle Loading (Maximum Weight per Axle)035500 lbs37000 lbs37000 lbs37500 lbs
Weight on Drivers136025 lbs142000 lbs148000 lbs148000 lbs150000 lbs172000 lbs
Engine Weight155975 lbs176000 lbs182000 lbs182000 lbs182000 lbs212750 lbs
Tender Light Weight82012 lbs90000 lbs102000 lbs126800 lbs107000 lbs96000 lbs
Total Engine and Tender Weight237987 lbs266000 lbs284000 lbs308800 lbs289000 lbs308750 lbs
Tender Water Capacity4752 gals5000 gals5000 gals6000 gals5000 gals4500 gals
Tender Fuel Capacity (oil/coal)8.8 tons8 tons8 tons4000 gals8 tons10 tons
Minimum weight of rail (calculated) on which locomotive could run57 lb/yard59 lb/yard62 lb/yard62 lb/yard63 lb/yard72 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter55"55"55"55"55"55"
Boiler Pressure180 psi200 psi180 psi160 psi180 psi210 psi
Cylinders (dia x stroke)20" x 26"19" x 32"19" x 32"23.5" x 32"19" x 32"21" x 34"
Tractive Effort28931 lbs35706 lbs32136 lbs43698 lbs32136 lbs48662 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.70 3.98 4.61 3.39 4.67 3.53
Heating Ability
Firebox Area192 sq. ft219.50 sq. ft198 sq. ft198 sq. ft228 sq. ft235 sq. ft
Grate Area31.63 sq. ft35.20 sq. ft34.18 sq. ft34.18 sq. ft35.20 sq. ft34 sq. ft
Evaporative Heating Surface2226 sq. ft2863 sq. ft2493 sq. ft2024 sq. ft3080 sq. ft3280 sq. ft
Superheating Surface375 sq. ft
Combined Heating Surface2226 sq. ft2863 sq. ft2493 sq. ft2399 sq. ft3080 sq. ft3280 sq. ft
Evaporative Heating Surface/Cylinder Volume235.46272.64237.40125.99293.30240.65
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation569370406152546963367140
Same as above plus superheater percentage569370406152634463367140
Same as above but substitute firebox area for grate area345604390035640367494104049350
Power L1556169145473583366316292
Power MT360.52429.37326.11347.56389.84322.59

Reference

Credits

Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.