Why is There Oil in the Coolant of Diesel Generator

Jul. 09, 2021

Coolant is also called antifreeze coolant. Antifreeze can prevent the coolant from freezing and cracking the radiator and damaging the cylinder block of diesel engine when the diesel generator unit is shut down in cold season. But we have to correct a misunderstanding that antifreeze is not only used in winter, it should be used all year round.


Recently, some users have reported that the diesel engine of generator set gradually found the phenomenon of oil splash in the radiator. With the passage of time, the oil in the radiator is more and more, and it comes out from the water inlet, and the phenomenon of the radiator turning over water is also more and more serious. What causes this? This article is a brief introduction of Dingbo Power.


Fault diagnosis: check the cylinder head gasket, oil cooler, torque converter cooler, no problem. There is no reduction of transmission oil in the transmission, and there is no water in the diesel engine oil, only a little less.

Why is There Oil in the Coolant of Diesel Generator


Because the diesel generator set of the user is used in the construction site and the construction site conditions are limited, the oil cooler and torque converter cooler of the same model are replaced first, and the fault still exists after running for 1H. Disassemble the cylinder liner and observe that there is no abnormality on the surface of the cylinder head. Erect the cylinder head with a steel ruler to check the plane of the cylinder head. There is no deformation. There is little carbon deposit in the piston combustion chamber and the combustion is normal. Take out 6 cylinder sleeves for inspection, and the wear is normal, and there is no sand hole or deformation on the surface.During the second test run, there is no oil splash in the radiator at the beginning. When the coolant temperature rises to 70 ℃, the oil splash begins to appear, and the higher the coolant temperature is, the more the oil splash is. Check the cylinder head carefully, remove the water baffle on both sides of the cylinder head, and observe the inside of the water channel. No abnormality is found, but there is a small amount of oil in the coolant overflowing from the water channel.


Cause of the fault: after starting the diesel engine, carefully observe the internal condition of the water channel, and find that the black oil wire floated along the water inside the water baffle on the exhaust pipe side of the cylinder head of cylinder 1 and cylinder 2, and carefully observe with the working lamp, and find that there is a tiny sand hole where the oil spilled. The sand hole is connected with the oil passage. When the machine is not started, the pressure on both sides is balanced; After starting, the oil pressure is higher than the water pressure. The oil flows to the circulating coolant under the action of pressure difference.


Troubleshooting: after replacing the cylinder head, the fault disappears.


What is the oil in the coolant of diesel engine?Through the above analysis, do you know the reason and how to deal with it? Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. is always committed to providing customers with comprehensive and intimate one-stop diesel generator set solutions. From the design, supply, commissioning and maintenance of the product, we will consider carefully for you everywhere. We will provide you with five-star worry free after-sales service, including pure spare parts, technical consultation, installation guidance, free commissioning, free maintenance, unit transformation and personnel training.


If you are interested in diesel generator or want to know more about diesel generator, please contact us by email dingbo@dieselgeneratortech.com, we can let you know more.

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