The first key aspect of a generator service involves the core engine and its fluid systems. This includes changing the engine oil and replacing the oil filter to remove accumulated contaminants and metal particles that can cause premature engine wear. Simultaneously, the fuel system is thoroughly inspected, which is especially vital for diesel generators where fuel can degrade over time and grow algae; the fuel filter is replaced to ensure a clean, steady supply to the engine. The cooling system is also checked for proper coolant levels, fan belt tension, and any signs of leaks in the radiator and hoses, as an overheating generator can quickly lead to catastrophic engine failure and a complete loss of power