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The "C630M" and "M630": Canada's Six-Axle 'Century'

Published: August 13, 2024

By: Adam Burns

Manufactured between 1967 and 1970, the M630 and C630M epitomized Alco, and subsidiary Montreal Locomotive Works' commitment to producing powerful and reliable locomotives capable of handling the demanding needs of freight transportation in North America.

Interestingly, MLW designs proved far more popular - and longer lasting - on Canadian railroads than in America.  Several C630M's - and their later M630 counterparts - remained in service until the mid-1990s while Alcos were long gone from Class 1 rosters in the States by the 1980s.

Known for its high-horsepower capabilities and sturdy construction, the M630 and C630M remains a significant model in the lineage of Canada's diesel locomotives.

CP Rail (Canadian Pacific) M630 #4566 is at Aberdeen Yard in Hamilton, Ontario on March 3, 1990. This is the old TH&B yard and shops. Doug Kroll photo.

Historical Context and Development

During the late 1960s, the railway industry was experiencing a shift towards high-horsepower locomotives that could haul heavier freight trains over longer distances with greater efficiency.

The C630M/M630 was based from Alco's powerful C630 series.  This C-C model was built between 1965 and 1967. It is part of Alco's 'Century' Series, which aimed to compete with EMD and GE's offerings during the highly competitive dieselization era in North America. The "630" in its name designates its six powered axles and 3,000 horsepower output, generated by the turbocharged, 16-cylinder 251E prime mover.

With its muscular appearance, the C630 has a wide, boxy design typical of Alco's Centuries. It measures 69 feet 6 inches in length and weighed approximately 197 tons, depending on optional additions.

The C630 was designed to be a direct competitor to similar models offered by GE (U30C) and EMD (SD40). Although it didn't achieve significant market penetration compared to its rivals, the C630 was well-regarded for its pulling power and reliability under challenging conditions. It found use with several American lines, including the PRR, Reading, Norfolk & Western, and Union Pacific among others.

Despite its operational merits, the model faced tough competition and was produced in relatively limited numbers, with only 77 units built. Alco's declining market position and the eventual cessation of locomotive production in late 1968 further limited the model's proliferation. However, the C630 remains a notable example of Alco's engineering efforts during its twilight years.

Following Alco's shutdown the company's Canadian arm continued producing its catalog, with greater success.  This included the C630 series.  The so-called C630M was built at MLW with the "M" designated "Canadianization" for locomotive requirements in that country. When Schenectady ended operations on December 31, 1968, production of this model continued at MLW but were re-designated as the M630.

The first C630M's produced included a group of 44 for Canadian National, #2000-2043, completed between August, 1967 and June, 1968.  Altogether, 56 were produced in this class. Following Alco's closure, a total of just twenty-nine M630's were built for Canadian Pacific, consituting the entirety of the series.

British Columbia Railway M630s #717 and #706, along with C425 #809, are entering North Vancouver with a freight from the north on May 25, 1984. Doug Kroll photo.

Design and Specifications

**1. Prime Mover and Engine:**

- **Engine:** ALCO 251E
- **Cylinder Configuration:** V16
- **Power Output:** 3,000 horsepower

At the heart of the M630 is the Alco 251E prime mover, a V16, four-stroke diesel engine delivering an impressive 3,000 horsepower. This high-horsepower engine provided the C630M/M630 with the capability to handle heavy freight loads and tough operational challenges.

**2. Wheel Arrangement:**

- **Configuration:** C-C (six axles, all powered)

Both models sported six-axle, High Adhesion (Hi-Ad) trucks.

**3. Dimensions and Weight:**

- **Length:** 69 feet, 6 inches
- **Weight:** 394,000 pounds (averag)

The M630's robust dimensions and weight contributed to its ability to pull substantial freight loads. Its design ensured that it could operate efficiently under heavy loads and across diverse rail environments.

Canadian National C630M #2022 is seen here at Montreal, Quebec in September, 1976. Warren Calloway photo.

Operational Use and Impact

**1. Canadian Pacific Railway**

Canadian Pacific was the only buyer of the M630, acquiring 29 examples while the railroad also purchased eight examples of the C630M (#4500-4507).

**2. Canadian National Railway**

Canadian National purchased only the C630M, as noted above with its 44 examples.

**3. Pacific Great Eastern Railway**

The Pacific Great Eastern, later British Columbia Railway, purchased four examples of the C630M, #701-704.

Data Sheet

Production Roster

C630M

M630

CP Rail M630 #4564 and C424 #4210 layover at London, Ontario on July 5, 1982. Doug Kroll photo.

Preservation and Continued Usage

Some M630 units continue to operate in limited roles, particularly within heritage and tourist railways. These units provide unique opportunities for rail enthusiasts to witness the powerful performance and distinctive features of the M630 in action.

Notable is Delaware-Lackawanna M630 #3007 (built as Pacific Great Eastern #706/BC Rail #706) and Western New York & Pennsylvania #631 (built as Canadian Pacific #4573). Lastly, former WNY&P #630 is now on display at the French Creek Valley Railroad Historical Society in Meadville, Pennsylvania.