Three Cylinder Steam Locomotives

There are only five surviving 3-cylinder rod steam locomotives in the United States (this, of course, does not include all of the 3-cylinder Shay type locomotives). They include:

  1. Southern Pacific 4-10-2 5021 at the Rail Giants Train Museum, Pomona, CA
  2. Union Pacific 4-12-2 9000 at the Rail Giants Train Museum, Pomona, CA
  3. Alton & Southern 0-8-0 12 at the National Museum of Transportation, St. Louis, MO
  4. London & North Eastern Railway 4-6-2 60008 at the National Railroad Museum, Green Bay, WI
  5. Baldwin 4-10-2 60000 at the Franklin Institute Science Museum, Philadelphia, PA

Southern Pacific 4-10-2 Number 5021

SP 4-10-2 #5042. Photo courtesy Carl Weber.
This is the only surviving Southern Pacific three-cylinder 4-10-2 (out of 49). The first of this type was built in 1925 by ALCO. The first axle is cranked to allow clearance for the center connecting rod on the second axle. The Southern Pacific named this wheel arrangement after their own name (Southern Pacific). The Union Pacific also had ten locomotives of this wheel arrangement (none survived). They named them "Overlands". This locomotive has 63 inch drivers. With its three cylinders, it could develop 4,100 HP. Its top speed was 60 MPH. They were used for both freight and passenger service over Donner Pass until it was determined that they were too rigid for the curves on that line. 5021 came to this museum under her own power. 5021 is in maintained in excellent condition.

Union Pacific 4-12-2 Number 9000

UP 4-12-2 #9000 builder's photo

In the mid 1920s many western railroads were using the 2-10-2 "Santa Fe" type and 2-8-8-0 Consolidation Mallet type locomotives for mainline freight trains. These locomotives were getting the job done but were limited to about 20 mph. The Union Pacific Railroad experimented with a three-cylinder 4-10-2 "Overland" type in 1925 and actually bought ten of them. The 4-10-2 locomotives were capable of slightly greater speed while being capable of pulling about 20% more tonnage. The Union Pacific wanted more and approached the American Locomotive Company about a design for a 4-12-2. The locomotive would have more power and would ride better at higher speeds.

The Union Pacific Railroad ordered a single locomotive with a 4-12-2 wheel arrangement and the American Locomotive Company delivered it in March of 1926. This locomotive was the first locomotive built with this wheel arrangement and was given the name "Union Pacific" for the Railroad that first used this type of locomotive. It was designated as Class UP-1 and assigned road number 9000. It had 67" diameter drivers, three 27" diameter cylinders (two with 32" stroke and one with a 31' stroke), a 220 psi boiler pressure, it exerted 96,646 pounds of tractive effort and weighed 495,000 pounds. Later in 1926, fourteen more of these locomotives were delivered from ALCO and were designated as Class UP-2 and given road numbers 9001 through 9014. These locomotives were similar to number 9000.

In 1928, 1929 and 1930 a total of seventy-three more "Union Pacific" type locomotives were added to the UP roster. Class UP-3 included twenty-three locomotives, which were assigned road numbers 9015 through 9029 for those used on the UP and road numbers 9055 through 9062 were assigned to the eight locomotives that were used on the OWR&N. Twenty-five locomotives were designated as Class UP-4 and were assigned road numbers 9030 through 9054. The last group of twenty-five was designated as Class UP-5 and included 9078 through 9087 for those locomotives used on the UP and numbers 9500 through 9514 for the fifteen that were used on the OSL.

The American Locomotive Company built all eighty-eight of these fast freight locomotives for the Union Pacific Railroad. They were three-cylinder locomotives with the third cylinder located in the center of the steam chest. The third cylinder drove an eccentric in the axel of the second pair of drivers. The fourth set of drivers were flangeless, but it was later determined that this was not necessary and a small flange was added to these drivers. They were built to the same basic specifications as its first delivered "Union Pacific" type locomotive, number 9000. The UP ran the 4-12-2 "Union Pacific" locomotives at 50 mph hauling 120 car trains.

There is one surviving UP 4-12-2 "Union Pacific" type locomotive. It is number 9000 displayed at the Los Angeles County Fairplex in Pomona, CA

Alton & Southern 0-8-0 Number 12

Alton & Southern 0-8-0 #12

This Alton & Southern 0-8-0 is located at the Museum of Transportation in St. Louis, MO. It was built by ALCO in 1926 and cost $57,598.20. It ran up 622,626 miles in service and was donated to the museum in 1948. Here is the locomotive data from its builders photo:

American Locomotive Company
New York
Class 080 S 243, "Three-Cylinder"Road Number 12
Built for the Alton & Southern
Gauge of TrackCylindersDriving Wheel DiameterBoilerFire BoxTubes
DiameterStrokeInside DiameterPressureLengthWidthNumberDiameterLength
4'-8 1/2"22"28"57"76"200 lbs96"84 1/4"239
5 1/2"
Wheel BaseWeight in Working Order - Pounds
DrivingEngineEngine & TenderDrivingEngineTender
16'-4"16'-4"54'-6 3/4"242500242500169400
FuelEvaporating Surfaces, Square Ft.Superheating Surface Square Ft.Grate Area Sq. Ft.Maximum Tractive PowerFactor of Adhesion
KindTubesFluesFire BoxArch TubesTotal
Soft Coal199187118623307174056.160600 lbs4.0
Tender Type 8-Wheeled.Capacity Water 9000 galsFuel 14 tons
Order No S-1560
September, 1926

London & North Eastern Railway 4-6-2 Number 60008

London & North Eastern 60008

This three cylinder Pacific, named Dwight D. Eisenhower, is displayed at the National Railroad Museum in Green Bay, Wisconsin. It was originally named Golden Shuttle but was renamed in late 1945. It was built by the LNER as the A4 class, introduced in Sept 1935. There were 35 in the class. When British Railways was formed in 1946 by the amalgamation of four "Groups", there was some number duplication on locomotives. Block numbers were allocated to the four former groups of locomotives. Former LNER locos were numbered in the series starting at 60000. That is how 60008 (formerly number 8) came about.


Boiler max. O.D.:6' - 5"
Grate area:41.2 sq. ft.
Heating surface firebox + combustion chamber:231 sq ft
Total evaporative surface:2576 sq ft
Length between tube plates:17' - 11.75"
Superheater surface:750 sq ft
Operating pressure:250 psi
Cylinders:(3) 18.5" dia by 26" stroke
Valve Gear:Walschaerts with Gresley derived motion for inside cylinder
Piston Valves:9"
Steam lap/Max travel:1 5/8" / 5 3/4"
Locomotive Weight:102 ton 19 cwt
Tender Weight:64 ton 3 cwt
Tender capacity:8 tons coal, 5000 gallons water
Axle weight:22 tons

Data from "British Locomotive Classes" Promotional Reprint Company 1996. First published by the Locomotive Publishing Company 1945 entitled Modern Locomotive Classes. The locos modified during the war, with sections of the streamline casing removed, so the weights may be wrong for your engine. Further, some engines had double chimneys with Kylchap exhaust systems. The record breaking engine Mallard (126 mph) was so equipped.

Baldwin Demonstrator Number 60000

Baldwin 3-cylinder 60000

With the year 1926 came an outstanding event in Baldwin's history, for at that time the Works was ready to build its sixty-thousandth locomotive. To symbolize this event President Samuel M. Vauclain planned and built a huge three-cylinder compound, high-pressure locomotive. It was of the 4-10-2 type and closely resembled engines with this wheel arrangement on the Southern Pacific Railroad. To safely accommodate the high boiler pressure of 350 lb. per square inch, a water-tube firebox was used.

From the book The Locomotives that Baldwin Built by Fred Westing

Built as a Baldwin demonstrator in 1926, this locomotive was used by various railroads around the country to show some of Baldwin's latest ideas. It was numbered 60000 to commemorate the 60,000th locomotive to be built by the Baldwin Locomotive Works. It ran successfully on either coal or oil as fuel. It also attained the highest power ever developed up to the time on the Altoona test plant, namely, 4,500 horsepower. This, at the time, exceeded the plant's capacity and restricted attempts to obtain greater power with additional tests. It has several features which made it unique:

  • It has a water tube firebox.
  • It has three cylinders.
  • It used compound steam expansion.

NOTE: If you look carefully under the smokebox front, you will see the center high-pressure cylinder and steam chest. This cylinder is angled downward to the back. The piston is connected via a crank to the second set of drivers.

The numbers 60000 appear on the cab side, and on the number boards and headlight of the engine. The tender lettering reads THE BALDWIN LOCOMOTIVE WORKS. The tender is a Vanderbilt with a short coal space and 6-wheel trucks. Here are a few more specifications on the 60000:

  • Wheel arrangement: 4-10-2
  • Cylinders: High pressure (1) 27x32 inches
  • Cylinders: Low pressure (2) 27x32 inches
  • Boiler diameter: 84 inches
  • Steam pressure: 350 psi
  • Driver diameter: 63.5 inches
  • Weight on drivers: 338,400 lbs
  • Total engine weight: 457,500 lbs
  • Total engine & tender weight: 700,900 lbs
  • Tractive force: 82,500 lbs

Although there were not any serious problems with it, the railroads rejected it because they found it overly heavy and complex and were wary of most of its features. Also, the 4-8-4 was quickly becoming the ideal high-speed, heavy freight and passenger locomotive. With only 100,000 miles on it (very little for a steam locomotive), it was returned to Philadelphia in 1928 and stored until 1932 when it was donated to the Franklin Institute Science Museum in Philadelphia, PA.

It is on display there today in the basement on a short piece of track. A hydraulic system is used to move the locomotive back and forth about fifteen feet. The demo was once propelled by a worm gear. It was changed over to a hydraulic system in the mid 1970s. By that time, the bearings in the drivers had become egg shaped, supposedly because of all the reversing, and some BLH retirees figured out how to replace them. The distance traveled inside the museum was staggering for such a short trip: conservatively, 30 ft/trip x 2 trips/demo x 5 demos/day x 360 operating days/yr = about 20 miles/yr, or about 400 miles in reverse by 1980.

Other 3-Cylinder Steam

Baldwin built a batch of 3-cylinder pacifics for the EFCB (Central of Brazil) in 1927. They were broad gauge machines (5ft 3") (Brazil Central had both 5'-3" and Metre gauge lines). One of these is preserved in working order and operates about once a month. It is stored at the Museum of the Immigrants in Sao Paulo.

3-Cylinder Steam Reference

  • 4-10-2: Three Barrels of Steam by Boynton.
  • Vintage Rails magazine, No 15, November/December 1998, Pentrex
  • Union Pacific Type Volume 2, by Kratville and Bush
All material Copyright ©
Wes Barris