Classic Streamliners - TRAIN​CYCLOPEDIA

Southern Pacific Class MC-2 Mallet Consolidation Cab Forward Steam Locomotive

The MC-2 class of steam locomotives were the first class to be ordered by and built for the Southern Pacific (SP) as cab forward locomotives. They were built in 1909 following the design of SP's MC-1 class built earlier that year. The success of this locomotive model led to the design and introduction of the AC class of 4-8-8-2 cab forward locomotives in the 1930s and 1940s.

In order to supply fuel oil from the tender to the opposite end of the locomotive where the firebox sat, oil in the tender was pressurized. Five pounds-force per square inch (34 kPa) of air pressure was sufficient to move the oil to the fire.

The two MC-1 locomotives built in May 1909 were rebuilt in 1923 as MC-2 class with uniform cylinders measuring 22 in (559 mm) diameter × 30 in (762 mm) stroke; these rebuilt locomotives weighed 437,000 lb (198,000 kg), like the as-built MC-2 class, but with 393,700 lb (178,600 kg) on the drivers. Most of the MC-2 class were modified from compound to simple with the same size cylinders by 1931. Except for numbers 4011 and 4013 (which were both scrapped by 1936), all of the MC-2 and the two former MC-1 locomotives were rebuilt again into class AC-1 with a higher boiler pressure, but lower overall tractive effort. The MC-2 rebuilds included installation of a new 4¼-BL Worthington feedwater heater as well.

SP used these locomotives until after World War II, retiring and then scrapping them in 1947 and 1948. The last locomotive of this class was scrapped on April 12, 1949, at SP's Sacramento shops.

Southern Pacific class MC-2 Overview

Type and origin
Power type: Steam
Builder: Baldwin Locomotive Works
Serial number: 34019, 34043, 34044, 34046, 34047, 34063-34067, 34093-34097
Build date: November–December 1909
Configuration: 2-8-8-2
Gauge: 4 ft 8 1⁄2 in (1,435 mm) standard gauge
Driver diameter: 57 in (1,448 mm)
Adhesive weight: 394,700 lb (179,000 kg)
Loco weight: 437,000 lb (198,000 kg)
Fuel type: oil
Boiler pressure: 200 psi (1.4 MPa)
High-pressure cylinder: 26 in × 30 in (660 mm × 762 mm)
Low-pressure cylinder: 40 in × 30 in (1,016 mm × 762 mm)
Performance figures
Tractive effort: 94,880 lbf (422.05 kN)
Operator: Southern Pacific Railroad
Class: MC-2
Number in class: 15
Numbers: 4002 – 4016
First run: February 4, 1910
Retired: 1946 – 1948
Disposition: scrapped

See also:

Cab Forward Locomotives

2-8-8-2 Locomotives

Steam Locomotives


An MC-2 Slideshow.

Related Products

(Click on image for more information)

SP Cab Forward Collection DVD.
Historic Rail - Shop Now!
Southern Pacific class MC-2 Number 4014 in 1910.
Baldwin logo.

Southern Pacific class MC-2 Number 4014 in 1910.

Southern Pacific herald. - NFL Jerseys and Gear
Enter the Classic Streamliners Bookstore.
Enter the Classic Streamliners Bookstore. - NFL Jerseys and Gear
Shop for Trains and Railroad Collectibles on eBay
Shop for Railroad and Train Collectibles on eBay