Withdrawal of heat from internal combustion engines is a major concern in today's automotive industry, mainly due to material constraints and components durability, in such a way that a well-designed cooling system may increase engine's reliability. In this sense, a numerical study is conducted to analyze the water flow inside MWM INTERNATIONAL’s high-speed diesel engine, in order to determine possible cavitation regions, which can reduce the heat transfer efficiency. The analysis is carried out with the help of computational fluid dynamics (CFD) commercial software ANSYS CFD. The flow is considered to be steady-state, turbulent, with heat transfer and the fluid is treated as a single phase. For this reason, the cavitation regions are identified through vapor pressure temperature, respectively. Based on those results, modifications will be made on the geometry, in order to avoid cavitation at water jacket regions.