skip to content
stan runge

#2659

ALCO S-1 and S-3

🇺🇸 United States ·built by American Locomotive Company· from 1940· models of 543+300 North American 660hp Bo′Bo′ switcher

🛤️ diesel locomotive diesel
10 photos from Wikimedia Commons · credits & licences
  1. 1. MCRY 7 20041010: The original uploader was Slambo at English Wikipedia .· CC BY-SA 2.0
  2. 2. A Chicago Great Western Alco S1 15 (25643393821): railfan 44· Public domain
  3. 3. CN MLW S3 8483 switching a reefer at the London, ONT. passenger station on July 4, 1966 (35670650571): Marty Bernard from U.S.A.· Public domain
  4. 4. Central Railroad of New Jersey S1 1024 at Elizabethport, CNJ Shops, on November 8, 1969 (25992008581): railfan 44· Public domain
  5. 5. Maine Central S1 958 at Waterville, ME yards on February 7, 1970 (25948409644): railfan 44· Public domain
  6. 6. NYCRR -871 Alco S-1 - PIER7 (11690889546): Sal Piro from Flower Mound, USA· CC BY-SA 2.0
  7. 7. S3 Diesel Electric Locomotive: SriMesh· CC BY-SA 3.0
  8. 8. ALCO S1 EFCB 3003: Sydney S. Correa· CC BY 3.0
  9. 9. Alco S1 Switcher 958: Cliff· CC BY 2.0
  10. 10. CCT 42, an Alco S1 waits for the mainline to clear near CSU Sacramento: sodai gomi· CC BY 2.0
Read about it on Wikipedia ↗
ALCO S-1 and S-3, photo 1 of 10
1/10 The original uploader was Slambo at English Wikipedia .· CC BY-SA 2.0

what is it?

The ALCO S-1 and S-3 are 660 horsepower (490 kW) diesel-electric switcher locomotives produced by ALCO and their Canadian subsidiary Montreal Locomotive Works (MLW). The two locomotives differed only in trucks, with the S-1 using ALCO's own Blunt trucks, and the S-3 using AAR type A switcher trucks. The S-1 was built between April 1940 and June 1950, with a total of 543 completed, while the S-3 was constructed between February 1950 and November 1953 (MLW until 1957) with total sales of 300.

base stats

  • power 492 kWpower output
  • weight 90.3 tin working order
  • built 543made in total

Bars compare against all trains: 600 km/h (maglev), 1,700 seats; power, weight and number built on a log scale up to 20 MW, 1,000 t and 20,000 built.

fun facts

  • First built 86 years ago, in 1940.
  • 492 kW is about 6 family cars (~85 kW each) flat out.
  • Weighs about as much as 15 African elephants (~6 t each).
  • 13.7 m long: about 3 cars parked nose to tail.

diesel locomotive: A diesel engine on board drives the wheels, usually through a generator (diesel-electric).

spec sheet

built
1940–1953
number built
543
kind
Diesel
traction
diesel
origin
🇺🇸 United States
builders
American Locomotive Company, Montreal Locomotive Works
top speed
—
power
492 kW
gauge
1,435 mm standard gauge
wheel arrangement
Bo'Bo'
length
13.7 m
weight
90.3 t

From the Wikipedia infobox and Wikidata. Blank means the sources don't say.

Sources: Wikidata Q4652300, Wikipedia: ALCO S-1 and S-3 (CC BY-SA 4.0).Updated 2026-10-25.

stan runge 7f71e88 source