Class S7 Specifications:
Locomotive Class: S7
Manufactured Country: Japan
Manufactured Company: Hitachi
Imported Year: 1977
Type of Locomotive: Diesel Hydraulic
Prime Mover: Cummins KTA 2300L
Maximum Power: 1020hp – 2100RPM
Maximum Speed: 88kmph
Axel Arrangement: B-B
Weight: 54 Tons (Power car only)
Length: 59 Feet (Power car)
Colour: Dark Red
No. of Units Imported: 10
Locomotive Numbers: 757-766
Class S7 DMUs’ came to Sri Lanka after few years S6 DMUs’ were imported. DMU’s were very popular among people due to the efficient service rendered by them. DMUs’ were mainly used for sub-urban & office trains because of the ease to control & less expenses. These reasons motivated SLR officials to import new DMUs’. These sets were similar to S6 sets in almost every feature. As other previous DMU’s this set was consist of a power car, 2 passenger cars & a dummy car. Power car was imported from Hitachi-Japan & other coaches were made locally using wood mostly. Sri Lankan workers made railway coaches for the final time for these sets.
These Class S7 sets were in Red colour originally & was painted in different colours like Green & Yellow, Green & Brown from time to time. These were operated in coastal line, KV line, Puttlam line & up to Rambukkana on main line.
Class S7 DMU had the engine (Cummins KTA 2300L) with the maximum RPM value (2100 RPM) out of the locomotives in Sri Lanka. Due to that reason internal parts of the engine was subjected to wearing quickly & different errors appeared from time to time. As in S6 DMUs’ the underframe of these DMUs’ were weak. Due to the difficulties of finding the spare parts, Class S7 DMUs’ also withdrawn from the service. However 766 & 762 power units were in service recently.
Credits to Gehan Chandika & Nipuna Dodanthenna.