Lowell Machine Shop 4-4-0 "American" Locomotives of the USA


Class Details by Steve Llanso of Sweat House Media

Class 14"" cylinders (Locobase 8810)

Data from Zerah Colburn, The Locomotive Engine (1851). Boiler pressure is an estimate.

See Locobase 8809 for a brief discussion of Zerah Colburn and the origins of the data.

In addition to boiler details, Colburn also gave the following data:

Water room (cu ft) 56.6

Steam room (cu ft) 33.2

Size of steam ports 10 x 1 1/4"

Size of exhaust ports 10 x 2 1/4". Compared to the other Lowell machine, these ports were a bit bigger, although they served a smaller boiler and cylinders.


Class 15 1/2"" cylinders (Locobase 8809)

Data from Zerah Colburn, The Locomotive Engine (1851). Boiler pressure is an estimate.

White (1972) notes that Colburn was a leading authority on locomotive design and that his pathfinding book was one of the first American texts to discuss locomotive design in a thorough and coherent way.

By way of illustration, Colburn published a table of "Five Different Patterns of Locomotive Engines", which included this engine and a slightly smaller one shown in Locobase 8810.

In addition to boiler details, Colburn also gave the following data:

Water room (cu ft) 69

Steam room (cu ft) 41.5

Size of steam ports 10 x 1"

Size of exhaust ports 10 x 2 1/8".

Specifications by Steve Llanso of Sweat House Media
Class14"" cylinders15 1/2"" cylinders
Locobase ID8810 8809
RailroadLowell Machine ShopLowell Machine Shop
CountryUSAUSA
Whyte4-4-04-4-0
Number in Class
Road Numbers
GaugeStdStd
Number Built
BuilderLowell Machine ShopLowell Machine Shop
Year18501850
Valve Gear
Locomotive Length and Weight
Driver Wheelbase
Engine Wheelbase
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)
Weight on Drivers
Engine Weight
Tender Light Weight
Total Engine and Tender Weight
Tender Water Capacity
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated)00
Geometry Relating to Tractive Effort
Driver Diameter60"66"
Boiler Pressure80 psi80 psi
Cylinders (dia x stroke)14" x 18"15.5" x 18"
Tractive Effort3998 lbs4456 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Firebox Area52.67 sq. ft56.40 sq. ft
Grate Area 8.25 sq. ft8 sq. ft
Evaporative Heating Surface676 sq. ft863 sq. ft
Superheating Surface
Combined Heating Surface676 sq. ft863 sq. ft
Evaporative Heating Surface/Cylinder Volume210.79219.53
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation660640
Same as above plus superheater percentage660640
Same as above but substitute firebox area for grate area42144512
Power L123432563
Power MT


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.