Why, What is the Reason, The Full Explanations Guide Answer

The loss of water or antifreeze in a vehicle's engine cooling system is a critical situation that can lead to engine overheating and severe mechanical damage. Modern internal combustion engines rely on a closed and pressurized cooling system to maintain optimum operating temperature. Fluid loss in this system generally occurs through two main mechanisms: external leakage or mixing into the internal combustion chamber. Correct diagnosis of the water loss problem is vital for the long-lasting and efficient operation of the engine. This academic review aims to analyze in detail why vehicles lose water, the technical reasons behind this situation, and potential failures in cooling system components. The technical reasons behind the water loss of vehicles stem from losses of integrity at various points in the cooling system. These losses accelerate due to the system operating under pressure and usually manifest themselves through visible leaks or evaporation. External Leaks in Cooling System Components The most common failures causing the coolant to leak outward occur in the basic components of the system. These components and their potential failures are as follows: 1. Radiator: Corrosion forming over time in the radiator cores, stone impacts, or vibration-induced cracks cause the fluid to leak out. Especially in radiators with plastic side tanks, leaks are frequently seen at the junction of plastic and metal. 2. Hoses and Connection Points: Rubber components such as radiator hoses, thermostat hoses, and heater hoses harden, crack, or tear due to excessive pressure over time. Loosening at the points where hoses are connected with clamps or the aging of gaskets also leads to leakage. 3. Water Pump: When the shaft seal of the water pump wears out or a crack forms in its body, fluid leakage begins. This leakage, seen in the form of dripping from the discharge hole at the front of the pump, usually indicates that the pump needs to be replaced. 4. Expansion Tank and Cap: Cracks can form in the expansion tank itself. A more critical reason is the failure of the tank cap. The cap is responsible for keeping the pressure in the system at a certain level. When the cap gasket or spring mechanism breaks, the system pressure drops and the boiling point of the water lowers, which causes the fluid to disappear by evaporating. This situation is considered one of the most insidious causes of water loss even though the vehicle does not overheat. Internal Leaks and Structural Damages More serious water loss causes that threaten the integrity of the engine are the mixing of the fluid into the combustion chamber or the lubrication system. 1. Head Gasket Damage: The burning or damage of the gasket between the engine block and the cylinder head creates a transition between the cooling channels and the combustion chamber or oil channels. In this case, the coolant leaks into the combustion chamber and is expelled from the exhaust as white smoke, or it mixes with the engine oil and discolors the oil. This is one of the most critical failures of the engine and requires immediate intervention. 2. Cylinder Head or Engine Block Crack: Thermal stress-induced cracks can form in the cylinder head or engine block as a result of overheating. These cracks also cause water to mix into the combustion chamber or oil, similar to head gasket damage. 3. Heater Core Leakage: Leaks occurring in the heating cores inside the vehicle cause the fluid to leak into the cabin and usually cause a sweet smell and fogging on the windows. The detection of these technical failures is generally carried out with professional diagnostic methods such as pressure testing, chemical tests, and the use of ultraviolet dye. The water loss of vehicles is based on a wide range of technical reasons, from a simple hose looseness to head gasket damage that threatens the structural integrity of the engine. Fundamentally, any leakage point in the closed and pressurized structure of the cooling system or a loss of integrity in the internal structure of the engine leads to water loss. Neglecting this situation causes the engine to overheat and leads to irreversible expensive damages. Therefore, regular maintenance and the immediate inspection of sudden drops in the coolant level by an expert technician is a mandatory precaution for the protection of engine health.