When the oil turns black, it should be changed
This understanding is incomplete. For the oil that does not add quiet dispersant, the color turns black is the expression that the oil has deteriorated badly really, but the lube oil that modern vehicle USES is added commonly have quiet decompose agent.
This calming agent will adhere to the film on the piston and black carbon wash down, and dispersed in the oil, reduce the engine high temperature sediment generation, so the oil after a period of use is easy to turn black, but at this time the oil is not completely bad.
As much oil as you can
The amount of oil should be controlled between the top and bottom of the oil ruler. Because too much oil will be from the cylinder and piston clearance into the combustion chamber burning carbon. These carbon deposits will increase the engine compression ratio and increase the tendency to produce knock; Carbon in the cylinder red hot state is also easy to cause early combustion, such as falling into the cylinder cylinder cylinder and piston wear, but also accelerate pollution oil.
Second, too much oil increased the crankshaft connecting rod stirring resistance, so that fuel consumption increased.
Additives are very useful
Really high quality engine oil is with a variety of engine protection function of the finished product, formula has contained a variety of additives, including anti-wear agent, and the oil is most particular about the balance of the formula to ensure the full play of all kinds of performance.
Addition of other additives can not bring additional protection to the vehicle, but easy to react with the chemical substances in the oil, resulting in the decline of the overall performance of the oil.
Oil is often added without changing
It is correct to check the oil frequently, but only supplement and not replace can only make up for the shortage of oil quantity, but can not fully compensate for the loss of oil performance.
In the use of oil, due to pollution, oxidation and other reasons, the quality will gradually decline, at the same time there will be some consumption, reducing the quantity.
A way to tell if the oil is out of date
The easiest way to check the oil shelf life is to observe whether the oil viscosity changes, to determine whether the smell of the oil has become lighter, to observe whether the color of the oil has changed. Among them, in the observation of oil color changes, to pay attention to the changes in the oil additives.
In addition, filter paper or electronic instruments can be used to check whether the expiration date of vehicle oil has passed. Oil to the moisture in the air, ambient temperature and light induction is strong, if long exposure to the air, by strong light irradiation, usually will fail. The use of oil after the expiration of the shelf life will cause great damage to the vehicle engine, such as poor lubrication effect, cooling effect will also be affected.
A method of identifying whether the oil contains too much water
According to the regulation, the allowable water content in the oil should be below 0.03%. When the water content of more than 0.1%, oil additives antioxidants, detergents dispersant will be lost, thus accelerating the oil oxidation process. The organic acid produced by oil oxidation and the acid oxide in engine exhaust gas react with water to produce inorganic acid.
These acids add to the corrosion of the engine. When there is more water in the oil, the lubrication of the oil becomes poor, viscosity drops, light lead to premature deterioration of the oil and machine parts rust; It also causes serious mechanical accidents such as engine shaft holding and burning tiles.
1, color method, clean the standard oil is blue translucent. The oil is brown with water in it. When the engine runs for some time, the oil is milky white with foam.
2, combustion method, the copper rod heat into the oil under inspection, if there is a "chip" sound, indicating that the oil contains more water. You can also check the oil into the test tube to heat, when the temperature is close to 80℃ to 100℃, the test tube produced a "pik" sound, it proves that the oil contains more water.
3, discharge method, after the engine stop, let the engine rest for 30 minutes or so, loosen open the oil plug, if there is water out, it means that the oil contains more water.