So How Can We Identify The Water Content in Engine Oil?

1. Color observation method. Clean and qualified engine oil is blue and translucent. If there is water in the engine oil, it will be brown. After the engine has been running for a period of time, the engine oil will be milky white and accompanied by foam.
2. Combustion method. Heat the copper rod and put it into the engine oil to be checked. If there is a "crackling" sound, it means that there is more water in the engine oil. The checked engine oil can also be injected into a test tube for heating. When the temperature is close to 80℃ to 100℃, a "crackling" sound is produced in the test tube, which proves that there is more water in the engine oil.
3. Water release method. After the engine is stopped, let the engine stand for about 30 minutes, loosen the drain plug, if there is water released, it means that there is more water in the engine oil.
How to choose the right specification of engine oil:
Since the engine oil has a great influence on the performance and life of the engine, the engine oil of the same series, use grade and viscosity grade should be selected in strict accordance with the provisions of the vehicle manual. The engine oil recommended in the vehicle manual is based on the engine performance and the temperature of the sales area. It has a certain guiding role in the selection of engine oil and leaves a large safety factor. It is also one of the prerequisites for claims during the engine warranty period. If there is no manual, you can choose the appropriate engine oil specification according to the following method.
1. Select the corresponding series of engine oil according to the fuel used by the engine. Gasoline engines use S series oil; diesel engines use C series oil; liquefied petroleum gas engines use liquefied petroleum gas special oil.
Selection of engine oil grade. Since the severity of gasoline engine working conditions is related to the presence or absence of additional devices and their types in the engine intake and exhaust systems, the gasoline engine oil grade can be selected according to the type of additional devices.
① Gasoline engines without additional devices can use SD grade oil.
② Gasoline engines with crankcase forced ventilation (PCV) devices can use SE grade oil.
③ Gasoline engines with exhaust gas recirculation (ECR) systems should use SF grade oil.
④ Gasoline engines equipped with catalytic converters or medium and low-end electronic injection systems should use SG grade or above oil.
⑤ For mid-to-high-end electronic fuel injection gasoline engines that use new materials and new technologies, oils above SJ should be used.
In addition, for cars imported from automobile producing countries such as Europe, the United States, and Japan, the use grade of gasoline engine oil can also be roughly distinguished according to the year of production. For example: SG grade oil was used from 1989 to 1993; SH grade oil was used from 1994 to 1996; SJ grade oil was used from 1996 to 2001; SJ or SL grade oil was used from 2001. This is because the later the production year of the car, the more its performance has been improved, and the working conditions of the engine oil are usually more stringent than those of cars produced in earlier years.
2. Selection of diesel engine oil use grade.
The use grade of diesel engine oil should be determined according to the reinforcement coefficient of the diesel engine, which represents the sum of the mechanical load and thermal load of the engine.
3. Selection of viscosity grade
The selection of engine oil viscosity should meet both low-temperature starting and high-temperature lubricity. Select the viscosity grade according to the region, season and temperature, and try to use multi-grade oil. In cold areas, the engine oil used in winter should be OW, 5W oil or OW/20 or 5W/20 multi-grade oil; in hot areas, in summer, 40 oil or 20W/40 oil should be used.
Select the viscosity grade according to the technical characteristics of the engine. For new engines, oil with lower viscosity should be used to ensure normal running-in during the service period; for engines that have been used for a long time and have greater wear, oil with higher viscosity should be used to maintain the required oil pressure and ensure normal lubrication.