Resumen

Analysis of engine oil condition based on health, contamination and wear. Case: Airport shuttle bus. RCTU [online]. 2025, vol.12, n.2, pp.80-89. ISSN 1390-7697.  https://doi.org/https://doi.org/10.26423/njb3gs46.

The study evaluates engine oil condition based on health, contamination, and wear of an airport shuttle bus under real-life operating conditions. It was proposed that, with systematic monitoring and operational corrections, the lubricant properties would be maintained within permissible limits. A descriptive experimental design was applied with three samplings every 250 h (0-750 h). Laboratory tests analyzed viscosity (ASTM D445), FTIR for oxidation, sulfation, nitration, and contaminants (ASTM E2412), ICP for metals and additives (ASTM D5185), and water by Karl Fischer (ASTM D4928). Permissible limits and statistical criteria (ASTM D7720) were used in data analysis. The results showed a 13-14% decrease in viscosity compared to the baseline; oxidation remained at 16; sulfation was high and stable at 21. Nitration, 6-7, all within established limits; at the same time, no contaminants were recorded in the samples. In the case of particles, Fe = 3-4 ppm, Al = 0-1 ppm and Cu = 1 ppm were detected, with Mo = 41 ppm per additive and a controlled decrease in Ca-P-Zn. It is concluded that the oil maintained its protective capacity within the measurement period. Finally, condition-based maintenance is viable, allowing for optimization of the oil change interval with potential impacts on costs, reliability and environmental compliance.

Palabras clave : condition monitoring system; maintenance engineering; tribology; CI engine.