The main reasons for engine oil getting water mixed in are as follows:
1. Engine oil getting water mixed in due to damage to the oil cooler. When the oil cooler is damaged, the cooling water outside can seep into the oil cooler, causing water to mix in with the engine oil.
2. Engine oil getting water mixed in due to leakage from the water plug. After several years of engine use, some water plugs may rust through due to the corrosion of scale, allowing cooling water to enter the oil passage from the water passage and flow down to the oil pan. This situation is also quite common, so it is necessary to frequently check the water plugs.
3. Engine oil getting water mixed in due to 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 can cause corrosion. After long-term operation of the engine, the seal is prone to failure. The cylinder liner seal is one of the main reasons for engine oil getting water mixed in, so when checking the cause of engine oil getting water mixed in, it is necessary to check whether the cylinder liner seal is intact.
4. Engine oil getting water mixed in due to cracks in the cylinder liner. When the heated cylinder liner is in direct contact with the cooling water, it is prone to cracking. Once a crack occurs, 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 problems such as poor engine combustion and white smoke. Generally, the cylinder liner is not prone to cracking, 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. Engine oil getting water mixed in due to 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 engine oil from getting water mixed in. 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 engine oil to get water mixed in. The damage to the cylinder head gasket is also an important reason for engine oil getting water mixed in. After each disassembly of the machine, it is advisable to use a new cylinder head gasket to avoid water leakage from the cylinder head gasket causing engine oil leakage and subsequent engine damage.
Summary: Engine oil getting water mixed in is a common fault in internal combustion engines. It can be determined whether engine oil has water mixed in by observing the appearance color of the oil, the oil level, and the oil cooler. If engine oil getting water mixed in is found, it can be checked from aspects such as the oil cooler, water plug, cylinder liner seal, cylinder liner, and cylinder head gasket to determine the cause of the engine oil getting water mixed in.