Between 1922 and 1925, seventeen more Class MT "Mountain" type locomotives were received from ALCO. They were numbered 1671 through 1680 (later changed to 471 through 480) and 1691 through 1697 (later changed to 491 through 497).
The last five Class MT 4-8-2s were delivered from the Baldwin Locomotive Works in 1926. These were numbered 466 through 470 and were very similar to the "Mountains" built by ALCO.
All Class MT "Mountains" had 27" dia. x 28" stroke cylinders, 69" drivers and with a 210 psi boiler pressure exerted 52,920 lbs of tractive effort.
Data from CofG 4 -1927 and CofG 6 -1947 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also Volume 75, pp. 349+. (Thanks to Chris Hohl for the valve gear ID and for his 29 November 2015 email noting the original 190 psi setting for the boiler.) The first 27 were delivered over a six-year period by Alco's Richmond works. Works numbers were
1919 58035-58037 (road #481-483) 1920 62384-62387 (484-487), 62417-62419 (488-490), 1922 63531-63532 (491-492), 1923 64584-64588 (493-497), 65265-65269 (476-480). 1925 66322-66326 (471-475). 1926 Baldwin works numbers were 58997-58998 in January, 59059-59061 in March. Total engine weight ranged from 316,000 lb to 326,500 lb. The class was delivered with a stated superheater area of 900 sq ft (83.6 sq m) and boilers set to 190 psi (13.1 bar). It wasn't too long before the Central changed the boiler's layout from its original arrangement of 198 2 1/4" tubes and added 61 sq ft (5.65 sq m) of syphons to the firebox heating surface. In fact, the last batch of Baldwins were delivered with syphons. Several of the engines had had their pressure settings raised to 200 psi by 1932 and by 1947, boilers on the entire class were set to 210 psi as shown in the specs. Somehow the superheater later gained 64 sq (5.95 sq m) ft of heating surface without changing the number, diameter, or length of flues. The increase might have represented a recalculation rather than any actual changes. These Mountains ran the CofGa mainlines pulling trains from the Midwest to Florida. Retirements began in 1948 and ended in 1953.
Principal Dimensions by Steve Llanso of Sweat House Media | |
|---|---|
| Class | MT |
| Locobase ID | 3103 |
| Railroad | Central of Georgia (CofGa) |
| Country | USA |
| Whyte | 4-8-2 |
| Number in Class | 32 |
| Road Numbers | 1671-1697/466-470, 471-497 |
| Gauge | Std |
| Number Built | 32 |
| Builder | several |
| Year | 1919 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 18 / 5.49 |
| Engine Wheelbase (ft / m) | 38.92 / 11.86 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.46 |
| Overall Wheelbase (engine & tender) (ft / m) | 86.08 / 26.24 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 218,200 / 98,974 |
| Engine Weight (lbs / kg) | 319,100 / 144,741 |
| Tender Loaded Weight (lbs / kg) | 189,700 / 84,323 |
| Total Engine and Tender Weight (lbs / kg) | 508,800 / 229,064 |
| Tender Water Capacity (gals / ML) | 9500 / 34.09 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 15 / 14 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 91 / 45.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 69 / 1753 |
| Boiler Pressure (psi / kPa) | 210 / 14.50 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 27" x 28" / 686x711 |
| Tractive Effort (lbs / kg) | 52,805 / 23951.97 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.13 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 178 - 2.25" / 57 |
| Flues (number - dia) (in / mm) | 36 - 5.5" / 140 |
| Flue/Tube length (ft / m) | 21.50 / 6.55 |
| Firebox Area (sq ft / m2) | 348 / 32.34 |
| Grate Area (sq ft / m2) | 66.70 / 6.20 |
| Evaporative Heating Surface (sq ft / m2) | 3702 / 344.05 |
| Superheating Surface (sq ft / m2) | 967 / 89.87 |
| Combined Heating Surface (sq ft / m2) | 4669 / 433.92 |
| Evaporative Heating Surface/Cylinder Volume | 199.46 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 14,007 |
| Same as above plus superheater percentage | 16,948 |
| Same as above but substitute firebox area for grate area | 88,427 |
| Power L1 | 18,405 |
| Power MT | 743.83 |