Perak Government 4-4-0 Locomotives in Malaya

Class Details by Steve Llanso of Sweat House Media

Class A ("Old A") (Locobase 1119)

Data from Dr. Jonathan DH Smith, "Malayan Railway steam locomotives" on his Standard steam locomotives website at [], last accessed 15 August 2023.

Several Eight-wheeler tank locomotives went to each of two main railways in Malaya between 1884 and 1898.

Perak' States engine works numbers were 342 (#2) in June 1884, 408 (#3)) in October 1886, 582 (#7) in 1893, 623 (#13) in February 1895, 656 (#16) in July 1896, and (681-682 ( #19-20) in 1898.

Selangor State's 1-3 (works 377-379) were turned out in August 1886; two bore the names Lady Weld and Lady Clementi (#3). By 1899, all three had substituted oil firing for the original coal fuel. Compared to burning "Backau wood" from mangrove tress, which cost $63.67 per 1,000 train miles, oil-fired As averaged $41.11. Given the immediate proximity of Malaya's oil fields, the decision to change fuels seems an obvious choice.

One of these had its tender bowled over by a bull elephant.

Principal Dimensions by Steve Llanso of Sweat House Media

ClassA ("Old A")
Locobase ID1119
RailroadPerak Government
Number in Class11
Road Numbers
Number Built11
Valve Gear
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)
Ratio of driving wheelbase to overall engine wheelbase
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)33,600 / 15,241
Engine Weight (lbs / kg)49,280 / 22,353
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)49,280 / 22,353
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)28 / 14
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)39 / 991
Boiler Pressure (psi / kPa)140 / 9.70
High Pressure Cylinders (dia x stroke) (in / mm)10" x 16" / 254x406
Tractive Effort (lbs / kg)4882 / 2214.44
Factor of Adhesion (Weight on Drivers/Tractive Effort) 6.88
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)
Grate Area (sq ft / m2)7 / 0.65
Evaporative Heating Surface (sq ft / m2)370 / 34.37
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)370 / 34.37
Evaporative Heating Surface/Cylinder Volume254.39
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation980
Same as above plus superheater percentage980
Same as above but substitute firebox area for grate area
Power L1
Power MT

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Wes Barris