Kansas City Southern 2-8-8-0 Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class G-1 (Locobase 437)

Data confirmed by KCS 1942-2 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. (Thanks to Chris Hohl for a 26 March 2012 email reporting the low tender capacity originally entered for this entry.)

G class were known simply as "Big Mallies." Calculated compound tractive effort was 122,683 lb. Purchase stimulated by success of 0-6-6-0s. Low-pressure, 41-in diameter pistons contained a volume of 24.44 cu ft each.

Assigned to KCS's Northern Division (KC to De Queen, Ark.). Two later refitted briefly to burn pulverized coal, but reverted to oil burning in 1930. Firebox heating surface included that provided by 92 sq ft (8.55 sq m) in four arch tubes and 127 sq ft (11.8 in a combustion chamber.

Delivered with the pressure set to 210 psi, 4 of the class -- 755, 752, 754, 750 -- had their settings changed to 220 psi. In 1927, the railroad increased the boiler pressure in 751, 752, 754, and 756 from 220 psi to 240 psi.

Class G-2 (Locobase 438)

Built at Brooks.

Calculated compound tractive effort was 110,400 lb or, using the ARA method, 103,700 lb. BDF, GDF calculated from ARA compound TE. Low-pressure, 41-in diameter pistons contained a volume of 24.44 cu ft each.

Class G-2S (Locobase 308)

Data from http://home.insightbb.com/~sammy56/folio/fo43-11.jpg (August 2002) has the blueprint elevation with all the data, supplemented by KCS 10 - 1950 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. (Thanks to Chris Hohl for correcting the builder attribution.)

Seven Big Mallies were rebuilt as four-cylinder simple articulateds by the KCS during World War II. Eliminating those massive, 41-inch diameter low-pressure cylinders permitted a speed increase of up to 50%. Firebox heating surface includes 102.5 sq ft (9.5 sq m) of thermic syphons and 28 sq ft (2.6 sq m) of arch tubes. Piston valves measured 12" (306 mm) in diameter. Fitted with a Worthington 6-A feedwater heater.

Although the diagram clearly shows a combustion chamber, its length isn't recorded.

Specifications by Steve Llanso of Sweat House Media
Locobase ID437 438 308
RailroadKansas City Southern (KCS)Kansas City Southern (KCS)Kansas City Southern (KCS)
Number in Class7108
Road Numbers750-756757-766752, 757-759,762,764,766
Number Built710
Valve GearBakerWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase15.50'15.50'15.50'
Engine Wheelbase50.50'50.50'50.50'
Ratio of driving wheelbase to overall engine wheebase 0.31 0.31 0.31
Overall Wheelbase (engine & tender)84.70'84.70'84.70'
Axle Loading (Maximum Weight per Axle)61700 lbs
Weight on Drivers466000 lbs474000 lbs476400 lbs
Engine Weight495000 lbs503000 lbs507300 lbs
Tender Light Weight218900 lbs206000 lbs206000 lbs
Total Engine and Tender Weight713900 lbs709000 lbs713300 lbs
Tender Water Capacity10000 gals10500 gals10500 gals
Tender Fuel Capacity (oil/coal)4266 gals4000 gals4266 gals
Minimum weight of rail (calculated)97 lb/yard99 lb/yard99 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter57"57"57"
Boiler Pressure210 psi225 psi250 psi
High Pressure Cylinders (dia x stroke)26" x 32"26" x 32"22.5" x 32"
Low Pressure Cylinders (dia x stroke)41" x 32" (2)41" x 32" (2)
Tractive Effort96627 lbs103529 lbs120789 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.82 4.58 3.94
Heating Ability
Firebox Area454 sq. ft414 sq. ft371.50 sq. ft
Grate Area88.30 sq. ft88.30 sq. ft88.31 sq. ft
Evaporative Heating Surface5231 sq. ft5170 sq. ft5304 sq. ft
Superheating Surface1434 sq. ft1459 sq. ft1459 sq. ft
Combined Heating Surface6665 sq. ft6629 sq. ft6763 sq. ft
Evaporative Heating Surface/Cylinder Volume266.02262.92180.09
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation185431986822078
Same as above plus superheater percentage226222423826935
Same as above but substitute firebox area for grate area116315113643113308
Power L18326890516364
Power MT315.12331.34605.82


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