Chicago, Indianapolis & Louisville (Monon) class J-4
In 1926, ALCO-Richmond built six Mikados for the Monon which were based on the USRA Light Mikado. But compared to this, the boiler and the cylinders got bigger, while the driver diameter was still 63 inches. They were numbered 560 to 565 and formed the class J-3. Three years later, ALCO-Schenectady built ten similar locomotives which were numbered 570 to 579 and formed the class J-4. These were among the last new steam locomotives built for this railroad. Later the J-4 was rebuilt with a trailing-truck booster and a larger boiler with thermic syphons and a feed water heater. Five also got roller bearings. Since the J-3 and the original J-4 were similar, the specs for the J-4 in the table are for the rebuilt variant. Both classes lived until the end of steam on the Monon. No. 578 shown in the photo was sold to the Tennessee, Alabama & Georgia in 1948 and numbered 402. It was scrapped in 1951.
Technical data
General
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Built | 1926 | 1929 |
| Manufacturers | ALCO | |
| Wheel arrangement | 2-8-2 (Mikado) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Wheelbase | 11.00 m | 11.25 m |
| Total wheelbase | 21.86 m | 23.31 m |
| Service mass | 143.8 t | 152 t |
| Adhesion mass | 112.3 t | 114.5 t |
| Total mass | 230 t | 251.7 t |
| Rigid wheelbase | 5.11 m | |
| Water capacity | 37,854 l | 45,425 l |
| Fuel capacity | 14.5 t (coal) | 18.1 t (coal) |
| Length | 26.83 m | |
Boiler
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Grate area | 6.596 m² | 7.451 m² |
| Firebox surface | 28.986 m² | 35.768 m² |
| Tube heating surface | 370.683 m² | 365.481 m² |
| Evaporative heating surface | 399.669 m² | 401.249 m² |
| Superheater surface | 91.974 m² | 108.325 m² |
| Total heating surface | 491.6 m² | 509.6 m² |
Power plant
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Driver diameter | 1,600 mm | |
| Boiler pressure | 13.8 bar | |
| Expansion type | simple expansion | |
| Cylinders | two, 686 x 813 mm | |
Power
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Power source | steam | |
| Estimated power | 2,386 kW (3,244 PS) | 2,610 kW (3,549 PS) |
| Starting effort | 280.0 kN | |
| Starting effort booster | 51.155 kN | |
Calculated values
| Property | J-3 | J-4 rebuilt |
|---|---|---|
| Factor of adhesion | 1 : 3.93 | 1 : 4.01 |
| Optimal speed | 51 km/h | 56 km/h |
| Power-to-weight ratio | 16.6 kW/t | 17.2 kW/t |
| Heating Surface Equivalent | 728.5 m² | 796.7 m² |
| Cylinder volume/HSE | 1 : 824.22 | 1 : 753.67 |
| Adhesive weight/Total | 1 : 1.28 | 1 : 1.33 |
| Tractive force/Heating surface | 1 : 11.90 | 1 : 11.48 |
| Grate area/Heating surface | 1 : 74.54 | 1 : 68.39 |
| Firebox/Tube surface | 1 : 12.79 | 1 : 10.22 |
| Total/Superheater | 1 : 4.35 | 1 : 3.70 |