When Kennet was built in 1947, a 30HP, 400rpm, single-cylinder EMX Widdop engine was installed. Up until 1952, all the Canal Transport boats were fitted with Widdop engines. They were built in Henry Widdop’s factory in Greengate, Keighley. The firm was established in 1897, and they commenced building marine diesels in 1916. On the Leeds & Liverpool Canal, the engines used were either single or twin cylinder engines. In the 1920s these were of the Invincible type, with EMX engines being fitted from the 1930s. The early engines were ‘hot bulb’, or semi-diesels, and required a blow lamp for starting, but a cartridge start was used on the EMX engines as they were true compression-ignition diesels. The cartridge was a little like a firework, and provided a heat source to ignite the diesel fuel when cold. The cartridge was screwed into the cylinder head before starting, with a cigarette end sometimes being used if there were no cartridges available. By 1955, Widdops had become a subsidiary of Associated British Engineering, and in 1959 they were taken over by British Polar Engines.
When the last steel Canal Transport Ltd boats were being built in 1952, it was decided to try Lister engines, and it was proposed that a JP3 engine should be installed. These were in production from 1931 to 1952 and had a capacity of 4312cc, with a bore and stroke of 4.5in by 5.5in, producing 35HP at 1200rpm. They were smoother than the Widdops, which were notorious for the vibration they created. Lister engines were used on many other canals. With Listers now one of the standard engines for British Waterways, the decision was made to replace the Widdops as required. Kennet’s engine was replaced, probably in 1963 with a new Lister HW2 or HW3 (1963-1970), a water-cooled version of the H series (1958-1970) which replaced the older JP and FR (1954-1964) engine types. (The HW2 had a capacity of 1853cc, and a bore and stroke of 4in by 4.5in, producing 24HP at 2000rpm). This engine was used while Kennet was employed on canal maintenance work. However, when the decision was made in 1985 to convert it to an exhibition boat, an older engine was thought more appropriate, and the current JP3 engine was fitted which had previously been used in a similar boat working on maintenance.