Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Oi"

OICA: Acronym for Organisation Internationale des Constructeurs d'Automobiles (i.e., International Organization of Motor Vehicle Manufacturers)

Oil: A substance that lubricates and cools the moving parts of the engine and reduces the formation of rust and corrosion. It contains additives which fights the corrosion of bearings, keeps small particles in suspension, reduces engine wear, and reduces oxidization, minimizes carbon, Lacquer, and gum formation. Oil comes in varying Viscosity weights suitable for efficient operation in cold and hot weather and for engines in varying states of wear. A mixture of hydrocarbons usually existing in the liquid state in natural underground pools or reservoirs. Gas is often found in association with oil.
Also See
Bedding-in oil
Break-in oil
Change the oil
Check the oil
Clean oil
Crude oil
Detergent oil
Diesel oil
Engine oil
Engine oil level warning light
Engine oil pan
EP gear oil
Flushing oil
Full-flow oil filter Gear-type oil pump
Gear oil
Hypoid gear hypoid oil
Hypoid oil
Low oil sensor
Low oil warning light
Lube oil
Lubricating oil
Micro oil filter
Mineral oil
ML oil
MM oil
Motor oil
MS oil
Multi-viscosity oils
Multigrade oil
Oil filter oil filter bypass valve
Penetrating oil
Piston ring, oil control
Pumping, oil
Single-grade oil
Straight-weight oil
Straight weight engine oil
Synthetic engine oil
Synthetic oil
Viscosity

Oil additive: Any one of a variety of chemicals added to engine oils to improve their performance. They include additives to increase viscosity at high and low temperatures; to inhibit corrosion, wear, and foaming; to prevent the formation of breakdown products caused by oil oxidation and to keep these in suspension

Oil and water extractor: See
Air transformer

Open bath: See
Oil bath suspension

Oil bath air cleaner: An Air cleaner that uses a pool of oil to insure the removal of impurities from the air entering the Carburetor.

Oil bath suspension: A suspension fork design that fills the lower part of the fork with oil, allowing the oil to be used for both damping and lubrication.

Oil binding: Condition in which oil layer on top of refrigerant liquid may prevent it from evaporating at normal pressure4emperature.

Oil bleed line: An external oil line which circumvents the evaporator pressure regulator or bypass valve to ensure positive oil return to the compressor when rpm are high and the system is under a low charge or clogged

Oil bleed passage: An internal orifice which bypasses the evaporator pressure regulator, the bypass valve or the expansion valve to ensure positive oil return to the compressor

Oil breather: Ventilated cap on oil filler pipe for allowing fumes to escape from the Crankcase.

Oil breather pipe: A crankcase breather pipe used prior to engine emission control systems to remove fumes and pressure from the engine crankcase. Also called Road-draft tube. The tube, which was connected to the crankcase and suspended slightly above the ground, depended on venturi action to create a partial vacuum as the vehicle moved. The method was ineffective below about 20 mph

Oil burner: An engine that consumes an excessive quantity of oil.

Oil can

A container with a long, thin nozzle for lubricating machinery.
A shallow dent in a panel that causes the panel to warp. The dent will spring back into its original shape with a characteristic sound if light pressure is applied but will not retain its normal shape once the pressure is released. It must therefore be straightened with body tools

Oil change: The act of draining and replacing the engine oil at regular intervals

Oil circulation: The passing of oil throughout the engine. The engine oil circulation is maintained by a gear-type pump with an output of up to 35 litres per hour

Oil-combination splash and pressure system: An engine oiling system that uses both pressure and splash oiling to accomplish proper lubrication.

Oil consumption: The amount of oil an engine uses

Oil control: See
Piston ring, oil control

Oil control orifice valve: A valve located in the feed line between cylinder and cylinder head

Oil control ring: A Piston ring designed to scrape oil from the Cylinder wall, the ring is of such a design as to allow the oil to pass through the ring and then through holes or slots in the Groove. In this way the oil lubricates the Cylinder walls and is returned to the pan rather than getting into the Combustion chamber where it might foul the Spark plugs and create Carbon on the Head of the cylinder. There are many shapes and special designs used on oil control rings. Often it is the third or fourth ring from the top. Also called Oil scraper ring

Oil cooler: This looks like a small Radiator used to cool off the engine oil or the Automatic transmission fluid. As air passes through the cooler, the temperature of the oil in the cooler is reduced. Some units reduce the temperature of the manual Gearbox and Differential lubricants in racing cars.

Oil cooler bypass valve: An oil-temperature-controlled valve which closes the oil circuit through the oil cooler when the oil is still cold; similar function as the thermostat in the engine cooling system. Engine oil is heated to a considerable temperature in engines subject to a high thermal load. This in turn greatly reduces the lubricating ability and the cooling capacity of the oil. Thermostats control the oil volume to the oil cooler, thus ensuring constant temperature of the oil

Oil dipstick: See
Dipstick.

Oil drain plug: The large bolt or plug that secures the drain hole in the Oil pan. It is sometimes fitted with a Gasket or O-ring to prevent leakage. Often the drain plug is magnetized so that any stray particles of iron will stick to it rather than lodge in some vital orifice. Also called sump drain plug

Oil drain valve: A valve in an upright oil filter housing which lets oil drain into the oil pan when the filter element is removed. It prevents oil spill

Oil duct: A pipe or passage through which oil flows under pressure. Also called oil passage or oil way.

Oiler

A Cam lubricator.
An Oil can

Oil filler cap: A cap covering the Oil filler hole

Oil filler hole: A hole at the top of the engine (usually in the rocker cover) through which new oil can be added after the Oil filler cap is removed.

Oil filter: Oil filter

A device used to strain the oil in the engine thus removing Abrasive particles. Some filters are a can-like container, others look like small Air filters which fit into a Canister. Most manufacturers recommend that the oil filter should be replaced at least every second oil change.
Also See
Centrifugal oil filter
Filter
Full-flow oil filter
Micro oil filter
Oil filter oil filter bypass valve

Oil filter bypass: See
Oil filter oil filter bypass valve

Oil filter bypass valve: A valve in or near the oil filter which routes the oil unfiltered directly to the lubricating points; it comes into operation when the oil filter is clogged so that pressure across the filter is higher than the pressure needed to overcome the oil filter bypass valve spring

Oil filter cartridge

The type of oil filter usually used on automotive engines which comes complete with filter and housing, and where both components are replaced together.
A paper or textile insert for the oil filter housing (quite commonly used on motorcycle engines where e.g., the main filter is a disposable cartridge, while a filter screen is located on the bottom of the oil pump)

Oil filter housing: A case surrounding an oil filter

Oil filter wrench: A special automotive tool for the removal and installation of oil filters; they come in a variety of shapes, e.g., as strap wrenches, chain wrenches, or special cup-style end cap oil filter wrenches

Oil flag: Oil flag

Also called surface flag, this indicates there is a problem with, or change in, the surface ahead. This commonly means there is oil on the track. It also can mean water or another substance causing a change in the racing surface. The number of stripes on this flag varies (some are yellow with two red stripes) but the meaning remains the same.

Oil full pressure system: See
Oil-full pressure system.

Oil-full pressure system: An engine oiling system that forces oil, under pressure, to the moving parts of the engine.

Oil gage: See
Oil gauge.

Oil gallery: A pipe or drilled passageway in the engine that is used to carry engine oil from one area to another.

Oil gauge: An instrument on the Dashboard which indicates the oil pressure as the oil is pumped through the engine. If this gauge shows a sharp drop, reads low, or lights up, it is possible that there is no oil in the engine. Stop the vehicle and turn off the engine. Check the oil level and replenish it as necessary. A vehicle with no oil in the engine could destroy an engine within a kilometer (or a mile). Also called Oil pressure gauge

Oil grade: A rating of an oil according to its viscosity

Oil groove: Recess designed to either accommodate or transport lubricant

Oilheads: Newer, air-and-oil-cooled BMW Boxer engines

Oil-immersed clutch: See
Wet clutch

Oiling splash system: Method of lubricating moving parts by agitating or splashing oil in the crankcase.

Oilless bearing: A sleeve bearing of porous material that depends solely on the porosity of the metal to store oil.

Oil level: The depth of oil in the oil pan, gearbox, transmission, power steering reservoir, or rear axle. Also see Engine oil level warning light

Oil level gauge: A dial on the instrument panel that indicates the oil level; operates when the ignition is switched on and stops shortly after the engine starts to run

Oil level sensor: A sensor mounted in the oil pan that supplies information on the engine oil level to the corresponding gauge

Oil level warning light: See
Engine oil level warning light

Oil life monitor: A vehicle computer that lets you know when to change the engine oil. This is not based on mileage, but on engine revolutions and operating temperature. Never drive your vehicle more than 16,000 kilometers or 12 months without an oil and filter change.

Oil lubrication: See
Clean oil lubrication

Oil-ML: Engine oil designed for light duty service under favorable conditions.

Oil-MM: Engine oil designed for moderate duty service with occasional high speeds.

Oil-MS: Engine oil designed for high speed, heavy duty operation or for a great deal of stop and go driving.

Oil pan: The removable metal chamber or bowl (usually of sheet steel or cast alloy) at the bottom of the Crankcase into which the oil drains to be stored. The Oil drain plug is found at the bottom of this pan and can be removed to allow the old oil to flow out of the vehicle during an oil change. The British term is sump. Also see Engine oil pan

Oil pan drain plug: Short fat bolt for draining the sump (when removed)

Oil pan gasket: A gasket fitted between the cylinder block and the oil pan

Oil pan guard: A shield fitted under the engine to protect the oil pan

Oil passage: A pipe or passage through which oil flows under pressure. Also called oil duct or oil way

Oil pick-up: A pipe or tube from the strainer to the oil pump in the oil pan

Oil pick-up pipe: A pipe or tube from the strainer to the oil pump in the oil pan

Oil pressure: The lubrication points of the engine will be lubricated sufficiently only if, in addition to the oil quantity required, the oil pressure is also sufficient; the oil pressure is maintained by the oil pump

Oil pressure gage: See
Oil pressure gauge.

Oil pressure gauge: An instrument on the Dashboard which indicates the oil pressure as the oil is pumped through the engine. If this gauge shows a sharp drop, reads low, or lights up, it is possible that there is no oil in the engine. Stop the vehicle and turn off the engine. Check the oil level and replenish it as necessary. A vehicle with no oil in the engine could destroy an engine within a kilometer (or a mile).

Oil pressure safety cutout: Motor protection device that senses oil pressure in the compressor. Is wired in series with the compressor and will shut it off during periods of low oil pressure.

Oil pressure sensor: A sensor mounted above the oil filter that supplies information on the engine oil pressure to the corresponding warning light

Oil pressure switch: A switch which indicates a drop to below the minimum permissible oil pressure by illuminating the Oil pressure warning light

Oil pressure warning light: An instrument panel light that illuminates when oil pressure falls below a certain level

Oil pump: The device located in the Crankcase used to force oil, under pressure, to various parts of the engine, it is driven by a gear on the Camshaft. There are two types Gear-type oil pump and Rotor-type oil pump.

Oil pumping: A condition where an excessive quantity of oil passes the Piston rings and is consumed in the Combustion chamber.

Oil pump strainer: A coarse-mesh metal screen on the bottom of the pick-up pipe that prevents foreign matter (such as lost washers, nuts and bolts) from entering the Oil pump

Oil rail: The part of the oil ring responsible for the seal between piston and cylinder wall and thus for the actual scraping off of the oil

Oil, refrigeration: Specially prepared oil used in refrigerator mechanism which circulates, to some extent, with refrigerant.

Oil reservoir: An underground pool of liquid consisting of hydrocarbons, sulfur, oxygen, and nitrogen trapped within a geological formation and protected from evaporation by the overlying mineral strata.

Oil ring: The lowermost Piston ring that scrapes off excess oil from the cylinder walls and returns it to the Oil pan via vents in the ring and Piston. The oil ring consists of up to three separate pieces. The two outside pieces are thin rings (rails), and the inner section of the ring is called the expander ring. The oil ring is also called the oil scraper ring

Oil screen: See
Oil pump strainer

Oil seal: A device used to prevent oil leakage past a certain area.

Also See
Grease seal
Valve oil seal

Oil sensor: See
Low oil sensor

Oil separator

A wire-mesh filter used to trap oil in the fumes drawn out of the engine by the crankcase ventilation system
Device to separate refrigerant oil from refrigerant gas and return the oil to compressor crankcase.

Oil slinger: A cone-shaped collar attached to a revolving shaft so that any oil passing that point will be thrown outward where it will return to the point of origin.

Oil splash system: See
Oil-splash system.

Oil-splash system: An engine oiling system that depends on the Connecting rods to dip into oil troughs and splash the oil to all moving parts.

Oil sludge: A thick deposit in the oil pan and elsewhere, of dirt and the products of combustion, partial combustion and oxidation of the oil (e.g. carbon particles, unburned hydrocarbons and oxides)

Oil sump: See
Oil pan

Oil tanker: A ship designed for transporting oil in bulk

Oil temperature gauge: A gauge which indicates the temperature of the engine oil

Oil thermal vacuum switch: (OTVS) a switch used by some GM vehicle to shut off vacuum to the early evaporation (EFE) valve when oil temperature reaches 150° F

Oil trap: See
Oil separator

Oil warning: See
Low oil warning light

Oil warning light: See
Low oil warning light

Oil way: A pipe or passage through which oil flows under pressure. Also called oil duct or oil passage