Oils for gasoline engines: types, how to choose, properties

Regardless of the car class the issue of the selection of the oil interests of all buyers. Work is recommended to trust the staff car service. They will select a suitable composition.

Specifications for gasoline engine oils

Compared with mineral and semisynthetic - synthetic benefit. But not everyone can afford them because of the cost. The structure was initially homogeneous, when the distillation just ended. It added to the mixture and additives to fit the existing standards.

In mineral fluids contain impurities of sulfur, among other substances. The engine will last a long time if the rate at 1 percent. Lifecycle halved if forgery acquire a parameter greater than 1%. Such formulations are cheaper, they are changed every 15 thousand kilometers.

In the manufacture of complex chains rely on chemical synthesis reactions, in order to achieve the required performance.

Synthetic endowed with the following advantages compared to other species:

• It needs to be replaced every 20-25 thousand kilometers. The term varies depending on operating conditions. In a smaller or larger side;
• long service life;
• the composition does not undergo oxidation and waxing;
• to overheating synthetic oil remains neutral - at critical temperatures not lose the positive qualities;
• fuel consumption is reduced, and the engine power is increased;
• the viscosity is lowered, due to which liquid penetrates into every corner of the engine.

Semisynthetic - average between mineral and synthetic compositions. Filling additives, quality and cost balance each other.

The degree of viscosity of the oil for gasoline engines SAE

• winter is marked by the letter W, next to which are the numbers from 0 to 25;
• SAE 20-60 - summer group;
• season - combine the properties of two types.

Performance properties are measured according to the American and the European standard: the ability to resist wear and cleaning properties, protection against oxidation and corrosion processes.

API and ACEA

S and C - two categories, which are divided into the compositions according to the findings of scientific research institute of oil from America. Categories are designed for diesel and gasoline. For machines up to 2000 using the marking of the letters SG, SH, SJ. After two thousand more are added to the SL and SM.

European manufacturers have developed a universal ACEA certification system. On liquid markings for trucks under this scheme is applied to the letter E, for diesel - the letter B. A letter A denotes the petrol engines.

The mean winter temperatures in the region - the basis for calculations when choosing winter fluid.

• 25W. At -5 degrees;
• 20W - to 10 degrees below zero;
• 15W. Up to 15;
• 10W - -20;
• 5W - to - 25;
• 0W - -30 and below.

On the promotion of the lubrication system need some time. We'll have to wait for starting the engine until the liquid comes to all moving parts. Activated mode, which is called "oil starvation". Noted an increase in wear and friction.

The better preserved fluidity at low temperatures - the faster everything moves. Such engines negative effects are not terrible.

In various areas take into account the following parameters:

1. The shear speed.
2. Pressure specific type.
3. Temperatures above zero.

Saving the viscosity significantly, even with such stringent conditions, otherwise it is not enough to cool the pairs involved in the friction to form a film coating. The task is important, if there is a question on the prevention of premature wear.

The partition specification parameter comprises setting temperature. It is calculated on the basis of laboratory studies.

Oil performance declines before when lower temperatures. Then, even full-time lubrication system will not help to pump the fluid.

Buyers not recommended to orient at the temperature at which the compositions harden, and SAE, viscosity class. The first is used only for promotional purposes.

Dimensionless acts viscosity index. It shows how a wide temperature range working oil. When a viscosity index of high - rate is less dependent on changes in the temperature of the plan.

quality class

In terms of API, formulations with universally recognized symbol SJ \ SF. They poured all engines on gasoline and diesel.

The ACEA classifications more fully take into account the structural characteristics of the engines of Europe. The same applies to the operating conditions in the European regions.

By individual tests ACEA requirements more stringent than the API. It is recommended to give preference liquids which have passed by ACEA tests.

For petrol engines use the designations A1, A2, A3. At diesel engines use the letters B1, B2, B3, B4, and so on.

A1 and B1 - low viscosity, high quality fluid. They are used to achieve maximum fuel efficiency. They are used where producers exhibit the relevant requirements.

A3-96 and B3-96 - classes whose characteristics are perfect.

differences compositions

The main difference lies in the molecular base of its structure. In the production process are connected with each other molecules having a given set of characteristics. Synthetic peak at chemical and thermal stability, unlike mineral.

Chemical stability means that there is no any transformations degrade performance.

Without thermal stability of viscosity and fluidity is not able to maintain its rate over a wide temperature range. Due to this the engine quickly and easily run in the cold. And in the highest-temperature areas present additional protection.

Problems

Problems arise if the earlier owner of the car used by the poor quality oils. Or broken intervals to replace it. Sealing elements because of that lose their elasticity - in part or in full.

Under the influence of mineral deposits inside the engine gradually "washed out." They are layer-by-layer. Due to the synthetic oil deposits peeled off from the inner surface. maslopriomnika grid for this reason can clog as oil passages.

Activated "oil starvation". Consequence is a quick failure. Stuffing box seal assume deposits. Disappear obstacles which prevent leakage.

It is not recommended to use synthetic fluids:

1. In the rotary-piston engine.
2. When there is a trial run with the relevant requirements or after major repairs carried out. For running is used only mineral oil of high quality.
3. With gland "stuffing." There may be leaking.
4. In the presence of sealing elements, have lost elasticity.
5. Since the inner surfaces in which deposition appeared.

Types of oils for gasoline engines

Mineral embodiments made directly from petroleum. It begins by distillation, more oil fractions are purified by selective acid or purification. For the preferred synthetic methods of organic synthesis. Basis - of the same petroleum feedstock processing but deeper.

There are several types of synthetic oils created from:

1. Esters.
2. Silicones or polyorganosiloxanes.
3. Glycols.
4. PAO.

These substances are mixed in different proportions.

The group of semi-synthetic. They are formed by adding to mineral oils substances obtained in organic synthesis. Engine oil without additives is called the base.

Polialfaoleiny. The synthesis reaction of ethylene - the so obtained material. Ethylene is included in the group of simple alkenes. Uniform molecular structure - one of the main, but not the only feature.

Liquids based on PAO synthetics have a number of advantages:

1. Prolong the service interval.
2. The engine runs steadily at low temperatures.
3. Cleaning - maintain engine cleanliness.
4. Saving chemical properties throughout the service life.
5. Resistance to oxidation processes.
6. Carbon consumption is low.
7. Friction is reduced, increasing savings.
8. With high antifriction properties.

How to choose oil for gasoline engines

• Compatibility Engine materials acquired composition;
• the degree of wear. When calculating its oriented to run;
• operating conditions, can be heavy or light, medium;
• engine type and year when it was created.

If you follow the manufacturer's recommendations, the engine will last long and faithfully. It allowed the use of oils with a little bit of a different class. Only it is important to remember the different operating ranges of temperature.

It is undesirable to use oil more viscous than those recommended by the manufacturers. The oil pump pumps the worst such liquids. Increased wear - one of the consequences in cases where taken more flowable material.

Operation and the degree of wear

Make adjustments necessary not only to the recommendations, but the climate in the region. It is not recommended to mix the compounds with different properties - they are not proven compatibility. Seasonal liquid the market is rare, it is used most often as a temporary option until you pick up the better.

Motor requires a different oil to various operation periods. Special varieties are used during the break-in. It is not recommended to change over a certain period.

After the completion of the running quality of the composition can be increased. Extending resource promotes viscosity, improved temperature stability. After some time, performance is reduced again.

At deterioration of motor fluid flow rate increases, as well as the likelihood of leakage. On one filling mileage of 10 thousand kilometers. When aggressive driving and the use of the diesel engine replacement more often.

As required driver monitors the level and composition of the refill. Not recommended rapidly switch from one brand to another. The share topped up, the new oil should not exceed 15 percent.

Synthetic not miscible with mineral. Incompatibility additives leads to a deterioration of properties, unpredictable change. Synthetic fluids blended with the other, if the manufacturer is the same.