MOTOR OIL (ENGINE OIL)

 A guide for you to know about motor oil. 

In this blog you will get to know what is the motor oil does means to you.

Here’s what we’ll cover:

• What is motor oil?
• What is in motor oil?
• What must a motor oil do?
• What is viscosity?
• SAE viscosity grades (oil weights)

What is motor oil? 

Motor oil is one of the most important factors in your engine’s performance and longevity.

Put simply, it’s the lubricant that prevents all those metal parts from tearing each other apart or welding themselves together into the world’s coolest boat anchor.

It reduces friction and heat while helping keep your engine clean. Without motor oil, your engine would destroy itself in a matter of seconds.

What is in motor oil?

Motor oil contains two fundamental components: base oils and additives.

The two work in tandem to produce the final product you put in your engine. Think of coffee as an analogy – the base oil is the water and the additive package are the coffee beans.

The base oils comprise the largest portion of the oil. They lubricate internal moving parts, absorb heat and seal the piston rings.

Motor oil base oils can be composed of 

1) petroleum

2) chemically synthesized materials

3) a combination of synthetics and petroleum (called semi-synthetic or synthetic blend).

Petroleum (or conventional) base oils are refined from crude oil. Contaminating elements such as sulfur, nitrogen, oxygen and metal components such as nickel or vanadium are inherent to crude oil and cannot be completely removed through the refining process. The oil refining process separates the various types of molecules in the oil by weight, leaving molecules similar in weight but dissimilar in structure, reducing performance.

Synthetic base oils, on the other hand, are highly engineered to include only beneficial molecules. As such, they contain no contaminants or molecules that don’t serve a designed purpose. Their versatility and pure, uniform molecular structures impart properties that provide better friction-reduction, optimum fuel efficiency, maximum film strength and extreme-temperature performance conventional lubricants just can’t touch.

Motor oil additives

The various chemicals that comprise a motor oil’s additive system provide anti-wear, anti-foam, anti-corrosion, acid-neutralization, viscosity-maintenance, detergency and dispersancy properties.

A few examples of chemical additives include zinc, phosphorus and boron. Striking the perfect balance of the proper additives in relation to the base oil is a tough balancing act for oil formulators, especially as vehicles grow more demanding and sophisticated.

What must a motor oil do ?

Lubrication

The main role of motor oil is to lubricate the engine parts, which are constantly subject to friction – the main cause of wear on engine parts. Lubricants reduce friction and wear, in turn reducing maintenance costs.

Cooling

During combustion, heat from combustion and friction between mechanical parts each cause engine temperatures to rise. Motor oil helps to trap, transfer and release this heat through the lubrication circuit, supplementing the engine coolant, which can only cool certain parts of the engine.

Cleaning 

The cleaning power of motor oil is fundamental to engine health. Microscopic deposits consisting of dust or combustion residue build up in the engine as it runs. Without motor oil, this residue would clog the engine and decrease its performance as the flow of motor oil continuously carries these impurities to the oil filter, where they are trapped.

Protection against corrosion

Fuel combustion generates corrosive acids that can damage metal engine parts. The additives within modern motor oils neutralise these acids, reducing the corrosive impact of acids. Nevertheless, when in contact with oxygen, motor oil may oxidise over time, no longer playing its corrosion-inhibiting role. That’s why you should change your motor oil regularly.

Sealing

Motor oil also enhances engine sealing, specifically the pistons and cylinders. It does it by forming a protective layer between the various components, sealing any clearances that may arise

What is viscosity?

Viscosity refers to the oil’s resistance to flow and is the most important property of an oil. The viscosity of oil varies with changes in temperature – thinner when hot, thicker when cold.

Although oil must flow at cold temperatures to lubricate the engine at startup, it must also remain thick enough to protect the engine at high operating temperatures. When an oil is used at a variety of temperatures, as with most engines, the change in viscosity should be as minimal as possible.

Wouldn’t it be handy to have a number that indicated the oil’s viscosity change? We do, and it’s called the Viscosity Index (VI). It is measured by comparing the viscosity of the oil at 40°C (104°F) with its viscosity at 100°C (212°F). The higher the VI, the less the viscosity changes with temperature changes and the better the oil protects the engine. Synthetics typically have a higher VI than conventional oils.

SAE viscosity grades (oil weights)

The Society of Automotive Engineers (SAE) has developed several viscosity classifications or grades, such as 5W-30, 10W-40 and 15W-50. People often refer to them as “oil weights.”

These viscosity grades (or oil weights) designate the specific ranges in which the particular oil falls.

The “W” indicates it is suitable for use in cold temperatures. (Think of the “W” as meaning “Winter.”) The classifications increase numerically; the lower the number, the lower the temperature at which the oil can be used for safe and effective engine protection. Higher numbers reflect better protection for high-heat and high-load situations.

The overwhelming majority of oils today are multi-viscosity, meaning they behave differently at different operating temperatures to provide the best of both worlds – good cold-flow when the temperature drops and reliable protection once the engine reaches operating temperature.

For example, a 5W-30 motor oil performs like an SAE 5W at 40ºC (104ºF) and an SAE 30 motor oil at 100ºC (212ºF).