Unidos de Yucatan 4-6-0 Locomotives in Mexico


Class Details by Steve Llanso of Sweat House Media

Class 39 Ticul (Locobase 11539)

Data from Baldwin Locomotive Works Specification for Engines, 1903, as digitized by the DeGolyer Library of Southern Methodist University Vol 26, p. 142. Works numbers were 23031, 23050 in October 1903; 23714, 23723, 23757-23759 in February 1904.

The narrow-gauge FC U de Y secured this septet of Ten-wheelers and named them Ticul, Calkini, Becal, Tinum (46), Tenabo (45), Hecelchahan (44), and Temax (43). Most of the class remained on the U de Y until their various scrapping dates, which ranged from 1949 to 1960. 40 was operated for a time during the revolution by the FC Constitutionalistas de Yucatan; it was returned to the U de Y in 1921. 44 was renumbered for the Nacional de Mexico (Unidos del Sureste) as 271.


Class 47 (Locobase 14493)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 54, p. 294. Works numbers were 44497-44498 in December 1916.

Very similar to the 1904 Ten-wheelers described in Locobase 11539, this pair of wood burners had four fewer tubes. The 1916 specs noted that the grades would come to a mild 0.5% and curves bent around in gentle 150 metre (492 foot) radii (11.7 degrees). They rolled on 40 lb/yard (20 kg/metre) rail.


Class 68 (Locobase 14494)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 54, p. 296. Works numbers were 45936-45937 in July 1917 and 58444-58445 in May 1925.

Not long after the N Escalante Company of New York bought and delivered two wood-burners to the Yucatan (Locobase 14493), another broker--Graham Hinkley & Company--bought two more Ten-wheelers. The only signficant difference was the choice of oil fuel. Eight years later came another pair built to the same specifications.

The 68 was renumbered 69 before it was sold to the International Railways of Central America as their #273.

Both of the later engines were sold to the Disney Corporation in February 1969. The 72 was renumbered 1, named Walter E Disney, and rebuilt in 1971. Its boiler jacket is painted red with gold trim and its cab green in time to open Walt Disney World in Kissimmee, FL. Sister 73 followed the same route, being renumbered 3, named Roger E. Broggie in honor of the man who satisfied Walt Disney's love of trains with the design of Disney's private Carolwood railroad and found these engines in the Yucatan. The 3's boiler jacket is green and its cab red. They are called the Twins because of their shared history from their production days.

See Locobases 967 and 12662 for the 4-4-0 and the 2-6-0 that also have had second lives on Disney railroads.

Principal Dimensions by Steve Llanso of Sweat House Media
Class39 Ticul4768
Locobase ID11,539 14,493 14,494
RailroadUnidos de YucatanUnidos de YucatanUnidos de Yucatan
CountryMexicoMexicoMexico
Whyte4-6-04-6-04-6-0
Number in Class724
Road Numbers39-4547-4868-69, 72-73
Gauge3'3'3'
Number Built724
BuilderBurnham, Williams & CoBaldwinBaldwin
Year190319161917
Valve GearStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)9 / 2.749 / 2.749 / 2.74
Engine Wheelbase (ft / m)18.25 / 5.5618.25 / 5.5618.25 / 5.56
Ratio of driving wheelbase to overall engine wheebase 0.49 0.49 0.49
Overall Wheelbase (engine & tender) (ft / m)42.21 / 12.8742.21 / 12.87
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)57,000 / 25,85557,000 / 25,85560,400 / 27,397
Engine Weight (lbs / kg)73,000 / 33,11273,000 / 33,11275,400 / 34,201
Tender Loaded Weight (lbs / kg)80,000 / 36,28750,000 / 22,68050,000 / 22,680
Total Engine and Tender Weight (lbs / kg)153,000 / 69,399123,000 / 55,792125,400 / 56,881
Tender Water Capacity (gals / ML)4000 / 15.152500 / 9.472500 / 9.47
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)1200 / 4.50
Minimum weight of rail (calculated) (lb/yd / kg/m)32 / 1632 / 1634 / 17
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)44 / 111844 / 111844 / 1118
Boiler Pressure (psi / kPa)180 / 12.40160 / 11160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)15" x 20" / 381x50815" x 20" / 381x50815" x 20" / 381x508
Tractive Effort (lbs / kg)15,648 / 7097.8213,909 / 6309.0213,909 / 6309.02
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.64 4.10 4.34
Heating Ability
Firebox Area (sq ft / m2)78.50 / 7.3078.50 / 7.2978.50 / 7.29
Grate Area (sq ft / m2)11.90 / 1.1112 / 1.1112 / 1.11
Evaporative Heating Surface (sq ft / m2)992 / 92.19969 / 90.02969 / 90.02
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)992 / 92.19969 / 90.02969 / 90.02
Evaporative Heating Surface/Cylinder Volume242.51236.88236.88
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation214219201920
Same as above plus superheater percentage214219201920
Same as above but substitute firebox area for grate area14,13012,56012,560
Power L1446839053905
Power MT518.43453.11427.60

  • UDY 3 (2016 Magick Kingdom photo by Wes Barris)
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