Minneapolis & St Louis 4-6-2 "Pacific" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class K1-32 (Locobase 6528)

Data from M&StL 1934 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. Superheater area is an estimate based on similar locomotives with the same flue arrangement, adjusted for length.

Pacifics of modest dimensions purchased to pull the North Star Limited. Lyndon Groth (of the http://www.cashgroth.com/ -- Minneapolis & St. Louis/Iowa Central/Chicago & Northwestern Website -- accessed 2 January 2008) gives us some detail about one engine in particular:"The 502 was the pride of M&StL President Lucian Sprague, who would occasionally take the throttle. She participated in the pageant at the Chicago Railroad Fair in September 1949 and went from the fair to the scrapper. In Gene Green's book "Minneapolis & St. Louis In Color" it is noted that 502 had been on the ground many times and as a result the frame had been patched so many times she had truly reached the end of the line."

The M & St L went for gas-electric doodlebugs for their meager passenger service and these locomotives were gradually retired beginning in 1939. The last K1 went out of service a decade later in 1949.

Specifications by Steve Llanso of Sweat House Media
Locobase ID6528
RailroadMinneapolis & St Louis (MSL)
Number in Class5
Road Numbers500-504
Number Built5
Valve GearBaker
Locomotive Length and Weight
Driver Wheelbase12.50'
Engine Wheelbase32.92'
Ratio of driving wheelbase to overall engine wheebase 0.38
Overall Wheelbase (engine & tender)62.83'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers137000 lbs
Engine Weight225000 lbs
Tender Light Weight165500 lbs
Total Engine and Tender Weight390500 lbs
Tender Water Capacity8500 gals
Tender Fuel Capacity (oil/coal)11 tons
Minimum weight of rail (calculated)76 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter69"
Boiler Pressure190 psi
Cylinders (dia x stroke)22" x 28"
Tractive Effort31720 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.32
Heating Ability
Firebox Area190 sq. ft
Grate Area48.80 sq. ft
Evaporative Heating Surface2346 sq. ft
Superheating Surface560 sq. ft
Combined Heating Surface2906 sq. ft
Evaporative Heating Surface/Cylinder Volume190.44
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation9272
Same as above plus superheater percentage11034
Same as above but substitute firebox area for grate area42959
Power L114785
Power MT713.77

If you have any railroad data such as diagram books, rail station plans or anything else that you would be willing to share, please contact us.