Sri Lanka Railways M4
Type and origin Power type Diesel-electric Builder Montreal Locomotive Works Order number M-6080 Serial number M-6080-01 to M-6080-14 Model MX-620 Build date 1975 onwards Total produced 14
Specifications Configuration: ​  • UIC Co′Co′ Gauge 5 ft 6 in (1,676 mm) Wheelbase Bogie: 11 ft 2 in (3,404 mm) Length 58 ft 3 in (17.75 m) Loco weight 93 long tons (94 t; 104 short tons) Fuel type Diesel Prime mover ALCO 251C3 Engine type 4 stroke V12 diesel Cylinders 12 Loco brake Air, Vacuum, Dynamic (Some vary)
Performance figures Maximum speed Design: 104 km/h (65 mph) Service: 65 km/h (40 mph) Power output 1,750 hp (1,300 kW)
Career Operators Sri Lanka Railways Class M4 Number in class 14 Numbers 743–756 Official name See table First run 1975

The Sri Lanka Railways M4 is a class of diesel-electric locomotive manufactured in Canada by Montreal Locomotive Works. Fourteen of the manufacturers' model MX-620 were imported in 1975.

This was the longest locomotive in the Sri Lanka Railways previously. All units are still operational. On regular operation they are not used beyond Polgahawela on the main line, and are not used on the hill country section. They used to travel on the full main line regularly until the previous decade.

They are painted in a livery of dark blue, light blue, silver with yellow striping; although No. 752 Point Pedro was painted in a special ICE (Intercity Express) livery.

Fleet

Gallery

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  Class M4 No. 745 "Ruwanveli"
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  Class M4 No. 747 "Kalani"
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  Class M4 No. 748 "Walawe"
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  M4 No. 749 "Dunhida"
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  Class M4 No. 754 "Menik"
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  Class M4 No. 755 "Mahaweli"
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  Class M4 No. 756 "Laxapana"