What does the engine oil:
-Reduces fuel consumption
-Facilitates the ignition
-Lubricates and reduces the wear
-reduces the friction
-Protects against corrosion
-Removes the carbon buildups and deposits
-Cools the engine parts
-Reduces the carbon deposits in the combustion chamber
-Seals the clearance of the pistons
Besides the above mentioned, the engine oil should have another key features too:
-It should extinguish the foam
-It have to separate /demulsify the water/
-It have to deposit the metal chips
What contaminates the engine oil:
-by-products of combustion, namely:
-products of oxidation
-other substances, forming deposits
Classification according to SAE
Single SAE grade oils: These motor oils are evaluated by their behavior
at different temperatures and so their viscosity grade is indicated.SAE
distributes them into 11 viscosity grades - so-called monograde oils. Six of
them are mainly for use at low temperatures: 0W, 5W, 10W, 15W, 20W, and 25W.
The letter W indicates Winter. For example the oils indicated with SAE 0W are
workable at lowest temperatures.
To determine the viscosity grade of winter monograde oils, the dynamic viscosity
(in mPa·s) under certain subzero temperatures is measured. The lower the viscosity
grade, the lower the temperature the oil can pass. For example, if an oil passes
at the specifications for 10W and 5W, but fails for 0W, then that oil must be
labeled as an SAE 5W. It cannot be labeled as either 0W or 10W.
The remaining five classes according to SAE are for use in high ambient temperatures,
ie these are summer classes. They are marked with SAE 20, 30, 40, 50 or 60.
Their kinematic viscosity is measured (in mm²/s, or centistokes, cSt) at 100 °C.
Multigrade oil. It has less of a tendency to change its viscosity with the
temperature changes and lubricates well as at low, and so at high temperatures.
This is a property, that is expressed by two marks by the standards of SAE, it is a
combination of the above two types of viscosity grades.
The first symbol, containing the the letter W is for its properties in winter, and the
second symbol shows the class of the oil by summer temperatures.
The oils marked with SAE 5W - ** or less are usually synthetic, while the standart
mineral oils have a viscosity in the range of SAE 15W-40 or SAE 20W-40.
Types of multigrade engine oils according to SAE.
0W-20; 5W-20; 0W-30; 5W-30; 10W-30; 0W-40; 5W-40; 10W-40; 15W-40; 20W-40; 5W-50;
10W-50; 15W-50; 20W-50; 10W-60;
Classification according to A.C.E.A. and A.P.I. Oils are evaluated according to
their ability to protect the engine against wear by work in lighter or heavier mode.
They are the same thing with the difference, that while the A.P.I. classification is
based on the requirements for engines in the United States, the classification of A.C.E.A.
is based on the requirements for the engines in Europe.
The designation A.P.I. is well known as "Donut". It consists of two characters denoting
the quality type of the oil and the engine type for which it is intended.
The first letter "S" means spark ignition, the first letter "C" means compression ignition,
ie the oil is for diesel engines.
The designation A.C.E.A. A indicates that the oil is intended for gasoline engines and
A.S.E.A. C - for diesel engines. "E" is the letter that corresponds to oils for diesel
engines, but for heavy trucks. A.S.E.A. put after the letters the numbers from 1 to 5 -
according to the load of the engine. For example A.S.E.A. A5 is used for very powerful
gasoline engines. The universal oils, that are suitable for any usage and load are
indicated by symbols A2 / B2 and A3 / B3.
Supplier: Rust LLC.