Engine Oil

Engine oil is stored in the oil pan or sump at the bottom of the engine. A pump forces the oil through a filter and then through a series of passages and galleries to lubricate the engine’s moving parts. The flow of also cools these parts. Rapidly moving engine parts actually float on a thin film of oil and never make contact with one another. This is called hydrodynamic lubrication and usually begins when an engine reaches the idle speed. Most engine wear occurs when a cold engine is first started, before the oil reaches its normal operating pressure and flow.

Diesel Engine Lubricating Oil

The main function of lubricant for diesel engine is the same as mentioned for gasoline engine. As the load in diesel engine is much higher it should have adequate antiwear properties. Diesel fuel contains a high level of Sulphur which burns to form oxides of sulphur , which in turn in the presence of water, form sulphur acids resting in high corrosion of engine parts. Hence the need of alkalinity reserve in the oil which is represented by its TBN or Total Base Number. Generally, the higher TBN value more the alkalinity reserve or acid neutralizing capacity the oil contains.

Synthetic Oil

T The advent of synthetic oil more than fifty years back opened up vastly improved and new alternative lubricant to mineral oil. But being very expensive, it is confirmed to the arcane world of motor sports and used for high performance cars. They are also widely used in developing countries for a number of reasons like improved overall engine performance, low oil consumption, long drain periods, less engine wear, improved engine cleanliness and faster starting. Taking into consideration the price tag and its efficacy, the option is left for consumer’s discretion.

Additives- what they do

Plain mineral oils cannot provide all the necessary functional properties that an engine requires. These plain mineral oils need fortification with chemicals/additives which when used in small quantities, import or enhance the desirable functional properties. Some of the types and reasons for their use are as follows:

Dispersants: Keeps sludge, carbon and other deposit- precursors suspended in oil.

Detergents: Keeps the engine parts clean from deposits.

Rust/Corrosion Inhibitors: Prevents or controls oxidation of oil, formation of varnish, sludge and corrosive compounds, limit viscosity increase.

Extreme Pressure (EP), Anti wear and friction modifiers: These form protective film on the engine parts and reduce wear and tear.

Metal deactivators: Forms surface films so that metal surface does not catalyze oil oxidation.

Pour Point Depressant: Lowers freezing point of oils assuring free flow at lower temperatures.

Anti-foamants: Reduces foam in crankcase and blending.

Checklist:

* Use only recommended engine oil. It should be in the owners manual and if you are unsure call up the manufacturer or the dealer.

* Change the engine oil every six months or five thousand kms, whichever is earlier.

* Make a note of your last oil change. At the time oil change make sure you use the recommended lubricants only. Check the packaging of the oil to make sure it is not spurious.

* Always buy from recognized dealers and outlets.

* Change oil filter at the time of an oil change.

* Never drive your vehicle if the engine oil level is low or it does not have engine oil.

* Most cars have an indicator for engine oil on the dashboard instrumentation plaster. If it indicates low oil do not drive the car till you refresh the engine oil.