Data from Roy V Wright (Ed.) 1922 Locomotive Cyclopedia of American Practice, Sixth Edition (New York: Simmons-Boardman Publishing Company, 1922), 1011; and "American Locomotive Company-'Mikado'-carga", p. 70 in Chilean State Railways (EFE) diagram book supplied in August 2025 by Allen Stanley from his extensive Rail Data Exchange collection. See also Martin Coombs, Chilean steam locomotive lists, Part 1, Broad gauge locos (v2.64, March 2026), p. 182, last accessed 27 May 2026.
Montreal Locomotive Works numbers were 59013-59032 in 1918. Alco-Schenectady added works numbers 63146-63165 in 1921 and 66560-66571 in 1925. The EFE diagram reveals that the first batch cost $183,257.66 per engine. The second twenty cost 207,487,24 each in 1922 gold dollars.
Martin Coombs explains that twenty were to be delivered initially, but ultimately only the first fifteen arrived in two ships. These engines had to wait for rail bridges at Puentes Chacabuco, Lampa, La Finca, Quemado, Rabuco, Aranda and Paso Hondo to be strengthened in order to run in I Zona.
Over the next few years, 33 more engines would join the class. A few seem to have been assembled in Chile from spare parts.
Most of the class served the EFE for almost 50 years with 53 remaining on the roster in 1968 and 31 in 1979.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Tipo 70 (700) |
| Locobase ID | 15019 |
| Railroad | Chilean State Railways (EFE) |
| Country | Chile |
| Whyte | 2-8-2 |
| Number in Class | 53 |
| Road Numbers | 701-753 |
| Gauge | 5'6" |
| Number Built | 53 |
| Builder | several |
| Year | 1918 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | / 4.72 |
| Engine Wheelbase (ft / m) | / 9.68 |
| Ratio of driving wheelbase to overall engine wheelbase | |
| Overall Wheelbase (engine & tender) (ft / m) | / 18.12 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 140,000 / 63,503 |
| Engine Weight (lbs / kg) | 194,500 / 88,451 |
| Tender Loaded Weight (lbs / kg) | 103,999 / 47,173 |
| Total Engine and Tender Weight (lbs / kg) | 298,499 / 135,624 |
| Tender Water Capacity (gals / ML) | 4998 / 18.93 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 8.80 / 8 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 58 / 29 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 56 / 1422 |
| Boiler Pressure (psi / kPa) | 182.20 / 1240 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 22.05" x 27.99" / 560x711 |
| Tractive Effort (lbs / kg) | 37,636 / 17071.42 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.72 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 157 - 2.008" / 51 |
| Flues (number - dia) (in / mm) | 26 - 5.394" / 137 |
| Flue/Tube length (ft / m) | 18.04 / 5.50 |
| Firebox Area (sq ft / m2) | 144.99 / 13.47 |
| Grate Area (sq ft / m2) | 42.09 / 3.91 |
| Evaporative Heating Surface (sq ft / m2) | 2288 / 212.56 |
| Superheating Surface (sq ft / m2) | 583 / 54.16 |
| Combined Heating Surface (sq ft / m2) | 2871 / 266.72 |
| Evaporative Heating Surface/Cylinder Volume | 184.95 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 7669 |
| Same as above plus superheater percentage | 9203 |
| Same as above but substitute firebox area for grate area | 31,701 |
| Power L1 | 11,354 |
| Power MT | 715.18 |