The distinct variations of the fuel properties, including calorific value, cold filter plugging point, density, kinematic viscosity, and oxidation stability, with the volumetric percentage of the jatropha oil methyl esters (JMEs) for the JMEs–diesel blends were determined. The JMEs–diesel blends were able to satisfy all of the biodiesel–diesel specifications except for their inferior oxidation stability. The blending ratio of the JMEs is recommended up to 40 vol.%, considering the variations of the cold filter plugging point and oxidation stability. The addition of pyrogallol to the JMEs at 250 ppm is remarkably beneficial for the oxidation stability of the JMEs–diesel blends. The correlations between fuel consumption,
exhaust gas temperature, brake thermal efficiency (BTE), and the concentrations of O2, CO2, NO, and HCs in the exhaust gas associated with output loading, the blending ratio of the JMEs, and the addition of pyrogallol have been successfully established. The higher output loading or blending ratio of the JMEs would increase the fuel consumption, exhaust gas temperature, and BTE as well as decrease the concentrations of O2 and HCs. The addition of pyrogallol exhibits a negligible influence on the combustion performance and pollutant emissions, except on the NO concentration. The higher blending ratio of the JMEs or the addition of pyrogallol would decrease the NO concentration, whereas higher
output loading has a positive contribution. The BTE increase with output loading and have maximum values of approximately 34%.