In Mexico, diesel is the second most widely used Fuel, representing 28% of national consumption, and is the largest emitter of greenhouse gases. In this Study, the diesel engine operated on a dual diesel/oxyhydrogen gas (OH2G) combustion mode. The OH2G supplied to the diesel engine is limited by the available volume in the combustion chamber. This allows combustion time and pressure to be maintained within the engine limits. Detonation-free combustion was observed, utilizing existing infrastructure and reducing diesel consumption and pollutant emissions. This Study shows the effects on the engine combustion chamber of the diesel/oxyhydrogen dual-combustion process after 500 h of operation. Two air-cooled, single-cylinder diesel engines with a displacement of 405 cm3 were operated; a D100 engine was operated with 100% diesel, and an OH210 engine in dual combustion (diesel/oxyhydrogen). Both engines were maintained at 40% of their maximum power load for 500 h. OH2G was generated in situ by alkaline electrolysis, and a flow of 2 sL min⁻1 was fed through the intake port during the engine’s suction stroke. Visual analysis, weight and dimensions of engine parts, metallographic analysis, and electrolyte carryover were used to determine the effects on component materials. In the dual-combustion diesel/oxyhydrogen engine, no structural damage to engine components was observed, although slight corrosion was observed on some components, such as the piston ring. Therefore, a more robust gas purification process will be implemented, and the injection system will be optimized.