The main reasons for water in engine oil are as follows:
1. Water in engine oil caused by damage to the oil cooler.
When the oil cooler is damaged, the radiator tubes break, and the water outside the radiator will seep into the oil cooler, resulting in water in the engine oil.
2. Water in engine oil caused by leakage of the water plug.
After several years of engine use, due to the corrosion of scale, some water plugs rust through, causing the cooling water to enter the oil passage from the water passage and flow down to the oil pan. This situation is also very common, so the water plugs should be checked frequently.
3. Water in engine oil caused by damage to the cylinder liner seal.
The wet cylinder liner is in direct contact with the cooling water, and the seal at the lower part of the cylinder liner can effectively prevent the leakage of engine oil and cooling water. During use, the seal is under certain pressure, and sometimes poor water quality causes corrosion. After the engine has been running for a long time, the seal is prone to failure. The cylinder liner seal is one of the main reasons for water in engine oil, so when checking the cause of water in engine oil, it is necessary to check whether the cylinder liner seal is intact.
4. Cracks in the cylinder liner can easily cause water in engine oil.
When the heated cylinder liner is in direct contact with the cooling water, it is easy to develop cracks. Once cracks occur, the cooling water will directly enter the cylinder and flow through the cylinder wall into the oil pan, causing the engine oil to turn white. White engine oil can lead to poor engine combustion and white smoke emissions. Generally, the cylinder liner is not prone to cracks, except in cases of improper maintenance, such as in cold winters when the cooling water does not have antifreeze added and freezes, which may cause the cylinder liner to crack. Another situation is when a hot cylinder liner comes into contact with relatively cold cooling water.
5. Water in engine oil caused by damage to the cylinder head gasket.
The function of the engine cylinder head gasket is to seal each cylinder and the corresponding water passage and oil passage, thereby preventing water from entering the engine oil. If the cylinder head gasket is damaged and the water circulation speed is fast, the water in the water passage will flow into the oil passage, causing water in the engine oil. The cylinder head gasket is also an important reason for water in engine oil. After each disassembly of the machine, it is advisable to use a new cylinder head gasket to avoid water leakage from the gasket causing engine oil leakage and engine damage.
Summary: Water in engine oil is a common fault in internal combustion engines. It can be determined by observing the appearance color of the engine oil, the oil level, and the coolant. If water in the engine oil is found, it can be checked from the oil cooler, water plug, cylinder liner seal, cylinder liner, and cylinder head gasket to determine the cause of water in the engine oil.