Troubleshooting:
Disassemble and inspect the diesel engine. If it is found that the cylinder head gasket is not damaged and the cylinder liner is not broken, there is no possibility of contact between oil and water. Practice has proved that if the cylinder head gasket or cylinder liner is damaged, there will be oil in the water tank and water in the oil pan of diesel engine. If there is no watermark in the oil pan of the diesel engine, it indicates that the fault is not caused by the above factors. The radiator of diesel engine may be faulty. Therefore, it is necessary to disassemble and inspect the oil radiator of diesel engine and carry out pressure test by pressurizing it with compressed air. If a small crack is found on the oil radiator, when the diesel engine works, the oil will penetrate into the cooling water jacket from the crack of the heavy truck radiator and be pumped into the water tank by the water pump.
Due to the limitation of maintenance conditions, please test the automobile after replacing the radiator of heavy truck to eliminate the fault. The heavy truck radiator of diesel engine is a plate structure, which is installed in the aluminum alloy shell cover. The bypass valve is installed in the radiator cover of the heavy truck. If the radiator of the heavy truck is blocked, the bypass valve opens at a pressure difference of 196kPa. The oil will directly enter the main oil passage without cooling. Heavy truck radiator is placed in cooling water circuit of diesel engine and connected in series with main engine oil channel. The temperature of cooling water is used to control the temperature of oil. Since the radiator is installed in the water cavity, once the radiator has tiny cracks, the oil will penetrate into the water cavity under the action of oil pressure (because the oil pressure is higher than the water pressure), then the water will be mixed together. The water on the diesel engine will be recycled to the water tank. If the oil leakage in the water tank is not removed in time, serious damage accidents will occur, such as burning out the bearings.
Better cooling system (Jiangsu) Company Ltd（U&C） is a professional manufacturer of automobile heat exchangers and heavy truck heat exchangers. If there is any question, please don't hesitate to contact us.
