They also produced 100 petrol-electric locomotives for the War Department Light Railways. These locomotives weighed 7 tons and had a 45 hp Dorman 4JO four-cylinder petrol engine driving a 30 kW DC generator at 1000rpm. This supplied current at up to 500volts to 2 traction-motors driving the 32inch wheels via a 6.68:1 reduction gear. The motors had an hourly rating of 25 hp, allowing the locomotive to haul 100tons at 5.2 mph. The two motors were run in parallel, with speed control by altering the generator voltage, and either motor could be cut out in event of a failure.