This research focuses on investigating an alternative fuel approach for diesel engines, specifically examining the impact of biodiesel when blended with diesel. Specifically, the study addresses relevant aspects of emission characteristics in single-cylinder diesel engines in terms of external characteristics. To conduct the experiments, three different fuels were tested: commercial diesel, a biodiesel blend with 10%, and 20% derived from palm oil (referred to as B0, B10, and B20, respectively). The results indicated that the addition of biodiesel in the diesel blend led to a reduction in CO pollution levels compared to the original diesel fuel. However, it was observed that the NOx pollution levels increased with the addition of biodiesel. Nevertheless, as the concentration of biodiesel increased from 10 to 20%, the NOx concentration tended to decrease. Overall, the incorporation of biodiesel resulted in decreased CO emissions. In conclusion, the integration of biodiesel and diesel oil presents a promising alternative for promoting the reliable and sustainable operation of diesel engines.