The present investigation analyzes the performance of a Hatz diesel engine that has 912 cubic centimeters (cc), stationary type, two cylinders, an air cooled feature and B10 (90% diesel and 10% palm biodiesel), using a test bench to improve statistically the repeatability and reproducibility of the runs. The experimental reference tests were carried out under defined conditions at a fixed speed of 1800 revolutions per minute (rpm) and four load levels: 35%, 50%, 65% and 80%. The repeatability analysis was based on the technical standard NTC-ISO / IEC17025. The variables of torque, fuel consumption (FC), air consumption (AC) and exhaust gas temperatures (EGT) showed an increase related with the load increase, showing a lower variation of AC and emissions. With the mechanism’s implementation of attenuator of air blows, adjustment mechanism for rpm and preheating air chamber for intake manifold, it was observed that the rpm presented the lowest statistical variability. The variables that presented the highest Pearson correlation with respect to the FC are the CO2, NOX and O2, this is because the engine does not have the Common Rail system, which causes the fuel supply to not be injected accurately and uniformly, therefore the evaluation of performance of the engine could not be repeatable.