South San Francisco Beltline 2-4-4 Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 4 (Locobase 13706)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 36, p. 99 Works number was 34845 in June 1910.

This powerful little oil-burning tank served the SSFB transfer line for years on its 70-lb/yard (35-kg/metre) rail before moving on to Algoma Lumber. Algoma sold the engine to the Modesto & Empire Traction Company in July 1942 as their #8. Nicknamed "Jeep", the 8 gave good wartime service before being scrapped in 1948.

Specifications by Steve Llanso of Sweat House Media
Locobase ID13706
RailroadSouth San Francisco Beltline
Number in Class1
Road Numbers4
Number Built1
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase 7.50'
Engine Wheelbase28.58'
Ratio of driving wheelbase to overall engine wheebase 0.26
Overall Wheelbase (engine & tender)28.58'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers75000 lbs
Engine Weight110000 lbs
Tender Light Weight
Total Engine and Tender Weight110000 lbs
Tender Water Capacity1600 gals
Tender Fuel Capacity (oil/coal)800 gals
Minimum weight of rail (calculated)0
Geometry Relating to Tractive Effort
Driver Diameter46"
Boiler Pressure160 psi
Cylinders (dia x stroke)16" x 24"
Tractive Effort18165 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.13
Heating Ability
Firebox Area88.50 sq. ft
Grate Area15 sq. ft
Evaporative Heating Surface1068 sq. ft
Superheating Surface
Combined Heating Surface1068 sq. ft
Evaporative Heating Surface/Cylinder Volume191.22
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2400
Same as above plus superheater percentage2400
Same as above but substitute firebox area for grate area14160
Power L13318
Power MT

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