Illinois Central 2-8-4 "Berkshire" Type Locomotives

Class 7000 (Locobase 48)

Boiler had Elesco feedwater heater, valve motion had limited cutoff. The very first 2-8-4 was originally built as a demonstrator locomotive, then sold to the IC. Boston and Albany A1 and Boston and Maine T-1s were very similar.

Drury (1993) says these engines "rode poorly above 40 mph, sometimes so roughly that the reverse gear wheel would suddenly spin into full forward gear. When that happened the throttle had to be closed at once and the valve gear returned to the proper position -- and several engineers broke an arm doing so." (203) The trailing truck also had a tendency to derail when backing up.

Modifications reduced cylinder size by an inch to 27" and raised BP to 265 psi in 1939, increasing tractive effort to 78,200 lb. One of the class -- 7038 -- was rebuilt in 1936 as a 4-6-4; see Locobase 1357.

Specifications
Class7000
Locobase ID48
RailroadIllinois Central (IC)
Whyte2-8-4
Road Numbers7000-7049
GaugeStd
BuilderLima
Year1926
Valve GearBaker
Locomotive Length and Weight
Driver Wheelbase16.50'
Engine Wheelbase41.70'
Ratio of driving wheelbase to overall engine wheebase 0.40
Overall Wheelbase (engine & tender)82.48'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers248000 lbs
Engine Weight388000 lbs
Tender Light Weight
Total Engine and Tender Weight0
Tender Water Capacity15000 gals
Tender Fuel Capacity (oil/coal)20 tons
Minimum weight per yard of rail on which locomotive could run103.33 lb rail
Geometry Relating to Tractive Effort
Driver Diameter63"
Boiler Pressure240 psi
Cylinders (dia x stroke)28" x 30"
Tractive Effort76160 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.26
Heating Ability
Firebox Area414 sq. ft
Grate Area100 sq. ft
Evaporative Heating Surface5164
Superheating Surface2111
Combined Heating Surface7275
Evaporative Heating Surface/Cylinder Volume241.53
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation24000
Same as above plus superheater percentage30964.12
Same as above but substitute firebox area for grate area128191.47
Power L130919.68
Power MT1099.45

Reference

Credits

Introduction and specifications provided by Steve Llanso of Sweat House Media.