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Class M8 841
Class M8 Specifications:
Locomotive Class: M8
Sub Classes: M8a
Manufactured Country: India
Manufactured Company: Diesel Locomotive Works (DLW) – Varanasi
Imported Year: 1996
Type of Locomotive: Diesel Electric
Prime Mover: M8: ALCO/DLW V16 – 251B 4-Stroke
M8a: ALCO/DLW V12 -251B 4-Stroke
Maximum Power: M8: 2600hp
M8a: 1950hp
Maximum Speed: 120kmph
Axel Arrangement: Co-Co
Weight: 112.8 Tons
Length: 17.2m
Colour: Dark blue & Light blue with Yellow strip
No. of Locomotives Imported: 10 (M8-8, M8a-2)
Locomotive Numbers: M8: 841-848
M8a: 877 & 878
This locomotive is somewhat similar to the Class M4, the Canadian ALCO locomotive in appearance & some technical facts. Reason for that is the prime mover or the engine of M8 was made according to a plan of ALCO Company. The prime mover of this is completely similar to ALCO 251B model. There is a story about why these engines were made in India.
Once India ordered a large number of locomotives from ALCO. But ALCO was not able to supply that much of locomotives on time. As a solution to this Indians asked to give permission & copyrights to build those locomotives in India. After India got the permission & Technology they built those remaining locomotives according to the ALCO plan on 1964. Now they produce & export locomotives to other countries too. About 2700 locomotives of this model is being used worldwide & about 1000 of them are manufactured in India.
Around 1996 two of these locomotives arrived Sri Lanka. Another 6 locomotives arrived sometime later & these 8 locomotives was categorized under Class M8. Two more locomotives were imported in the second phase & was categorized under the sub-class M8a. Power of M8a is lower than the power of M8 & it’s slightly short in length when compared with M8.
These heavy & high-powered machines was the longest & most powerful locomotive in that time. These are most often used for Express trains & for trains with 15-18 carriages. Some years back Samudradevi & Maho Office Trains were hauled by a M8. This loco have the ability to pull about 20 wagons. Now those trains are hauled by Class S10 DMUs.
These locomotives are most often used in Nothern, North-Eastern & Coastal lines. Due to the length of the bogie & the length of the locomotive is equal to M4 these locos don’t run on upcountry line, Matale line & KV line. And these are less seen in Puttlam line.
M8a locomotives were imported in 2001. Its prime mover was different to the original ALCO engine. These had 12 Cylinders while M8 had 16 Cylinders. It’s said that these are specially designed for Sri Lanka. The objective of importing M8a was using them for up country lines. But it wasn’t successful due to a failure in dynamic braking system.
Most of the parts of this locomotive are designed using Recycled iron. Due to this major problems occur is heavy rusting. All of these locomotives are subjected to this problem now.
At the time these were imported to Sri Lanka it had strip like cowcatchers which can be normally seen in Indian locomotives. SLR thought that these cowcatchers don’t suit Sri Lanka & they made new cowcatchers & replaced them with the old ones. M8a locos were sent to Sri Lanka with these new cowcatchers fixed.
M8s had only one Head light. Therefore Double head lights were fixed to all locomotives. In early days the outer cover of the locomotive had to be lifted up to repair the engine. This was a bothersome task & local engineers re-made the outer cover with side doors. It is said that Indian Company followed us & changed the above mentioned parts after SLR did these changes.
All of these locomotives are still in service. These can be known as the third powerful loco in Sri Lanka (1st-M10 2nd-M9). And these locomotives emit a lot of smoke due to the low standards & 16 Cylinders of the engine.
Credits to Gehan Chandika & Nipuna Dodanthenna.
Photo Gallery

The appearance of M8 when imported
Photo: Sri Lanka Railway Museum

Class M8a 877 at Veyangoda

Control Panel of M8

Class M8 841

M8 843 at Electric Locomotive Shed Maradana

M8 841

Interior parts

Class M8 845 hauling an office train

M8 845

M8 842
thanks for the info…..enjoyed seeing and filming one of these at Colombo