Classic Streamliners - TRAIN​CYCLOPEDIA

Historic Rail - Shop Now!

Chicago, Rock Island and Pacific Railroad EMC AB6 diesel locomotive No. 750 at Limon, Colorado, July 7, 1940.

Electro-Motive Company logo.
Rock Island herald.
Chicago, Rock Island and Pacific Railroad EMC AB6 diesel locomotive No. 750 at Limon, Colorado, July 7, 1940.

EMC AB6 Diesel Locomotive
The EMC AB6 was a type of diesel locomotive built exclusively for the Chicago, Rock Island and Pacific Railroad (the "Rock Island Line") by General Motors' Electro-Motive Corporation and delivered in June 1940. Two examples were built, numbered No. 750 and No. 751. They were built for the Rocky Mountain Rocket passenger train, which travelled as a unified train from Chicago, Illinois, to Limon, Colorado, but then divided; with one segment going to Colorado Springs, Colorado, and the other to Denver, Colorado. The Rock Island desired a locomotive that could look like an integrated part of the train during the Chicago-Limon portion of the route, but could then be operated independently to take three cars to Colorado Springs. A regular, cab-equipped A-unit could have been purchased, but that would have ruined the streamlined look of the train, so the RI had EMC build a flat-fronted locomotive based on an E-series E6B (B unit) but with an operating cab, headlight, pilot, and other features to enable it to operate as an independent locomotive.

Since the small three- and four-car trains the units would have to haul independently were very light, the AB6 pair were built with only one 1,000 hp EMC 567 V12 engine, and a baggage compartment where the second engine would have been. Later, with increasing trainloads, the baggage compartment was replaced with a second engine.

In 1965, the units had their steam generators replaced with head-end power and were reassigned to push-pull suburban service in the Chicago area. In this form, they lasted until the mid-1970s.

EMC AB6 Overview

Type and origin
Power type: Diesel-electric
Builder: Electro-Motive Corporation (EMC)
Build date: 1940
Total produced: 2
AAR wheel arrangement:          
    New: A1A-3
    Later: A1A-A1A
Gauge: 4 ft 8 1⁄2 in standard gauge
Prime mover: EMD 567, 1 x, later 2 x
Engine type: V12 Two-stroke diesel
Performance figures
Power output new: 1,000 hp
Power output later: 2,000 hp
Operators: Rock Island
Numbers: 750 and 751
Delivered: June 1940
Retired: mid-1970s
Disposition: Both scrapped 1973–74

See also:


EMC-EMD Diesel-Electric Locomotives

EMD 567 Prime Mover

Chicago, Rock Island and Pacific Railroad

Rocky Mountain Rocket Passenger Train

Diesel-Electric Locomotives

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