Engine oil

Motor oil, engine oil, or engine lubricant is any of various substances (comprising oil enhanced with additives, for example extreme pressure additives) are often used for lubrication of internal combustion engines. The main function of motor oil is to reduce wear on moving parts; it also cleans moving parts from the sludge, inhibits corrosion, improves sealing, and cools the engine by carrying heat away from moving parts.

Motor oils are derived from petroleum-based and non-petroleum-synthesized chemical compounds. Motor oils today are mainly blended by using base oils composed of hydrocarbons, polyalphaolefins (PAO), and polyinternal olefins (PIO), organic compounds consisting entirely of carbon and hydrogen. The base oils of some high-performance motor oils contain up to 20% by weight of esters.

On September 6, 1866 American John Ellis founded the Continuous Oil Refining Company (Later to become Valvoline). While studying the possible healing powers of crude oil, Dr. Ellis was disappointed to find no real medicinal value, but was intrigued by its potential lubricating properties. He eventually abandoned the medical practice to devote his time to the development of an all-petroleum, high viscosity lubricant for steam engines – then using inefficient combinations of petroleum and animal and vegetable fats. He made his breakthrough when he developed an oil that worked effectively in high temperatures. This meant no more gummed valves, corroded cylinders or leaking seals. In 1873 Ellis officially renamed the company to Valvoline after the steam engine valves the product lubricated.

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