Engineering designs are important in engine production. This research aimed at incorporating engineering principles and practices into the developed single piston diesel engine at Kevoton. Tests on the already innovated engine were carried out to evaluate the performance of the existing engines in terms of power, torque, rpm and exhaust temperature. Designs of the major components were generated together with material selection, which helped in determining whether the used material was appropriate for engine production. Results showed that the engine runs at a speed of 1800 rpm, a torque of 5 Nm, and a power of 10 HP with 2.4 liters per hour of fuel. The major components of the engine include the engine piston, the crankshaft, connecting rod, cylinder head and the camshaft. The power obtained after carrying out the new design was 13 HP, with a 5 Nm torque as well as 1 liter of fuel consumed per hour. It was realized that some components were not meeting the design specifications and the design was below the minimum required power of 13 HP. Power produced was less than 13 HP that was required to handle the purpose of engine manufacture, the engine was designed to be a prime mover to do most of the local. It was identified that the need of the engine should be considered as a primary requirement when coming up with the designs, the choice of injectors affect the amount of exhaust and engine testing requires consideration while designing an engine.