The Effect of Leaks in the L.O Cooler Tube on Temperature Increase in the Auxiliary Engine of KM. Wilis

Abstract

The auxiliary engine is one of the most important systems in ship operation, which depends on the stability of the lubrication and cooling systems to maintain engine performance. One of the vital components in this system is the L.O Cooler (Lube Oil Cooler), which functions as a heat exchanger to keep the lubricating oil temperature within safe operating limits. This study aims to analyse the causes, impacts, and technical solutions for the temperature increase caused by leaks in the L.O Cooler Tube. The research was conducted on the KM Wilis ship, owned by PT Pelayaran Nasional Indonesia, using a qualitative descriptive approach. The methods used included direct observation, technical interviews with ship engine personnel, and visual documentation of the L.O Cooler and related cooling systems. Lubricant temperature and oil pressure data were also analysed to support technical interpretation. The results of the study show that leaks in the L.O Cooler Tube cause cooling water to mix into the lubrication system, resulting in a decrease in oil viscosity and disruption to the lubrication function. This condition causes the lubricant temperature to rise beyond the safe threshold and increases the risk of wear on components such as bearings and pistons. The solutions implemented include replacing the Tube, cleaning the cooling lines, and periodically monitoring the temperature through sensors and recording machine operations.