Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "So"

SO₂: Abbreviation for Sulfur Dioxide Acid deposition, commonly called acid rain, occurs when sulfur dioxide and, to a lesser extent, nitrogen oxides (NOx) emissions are transformed in the atmosphere and return to the earth as dry deposition or in rain, fog or snow. Roughly 23 million tons of SO₂ is emitted annually in the United States, according to the U.S. EPA. The combustion of natural gas produces virtually no SO₂ and, with proper design, far less NOx than combustion of coal or fuel oil.

Soak: See
Heat soak
Hot Soak

Soaking time: The time required before a dry-charged battery is ready for use after being filled with acid

Soapstone: Lubricant used to prevent sticking between tire and tube.

Society: See
Classification society
Milestone Car Society

Society For Testing Materials: See
American Society For Testing Materials

Society of Automotive Engineers: (SAE)
Also see
SAE.

Society of Motor Manufacturers and Traders: (SMMT) An official organization of the British motor industry

Sock: The fuel pick up strainer in the fuel tank. The sock is made of saran, so water won't enter until the sock is entirely engulfed in water.
Also see
Inlet sock

Socket

A hollow part or piece adapted or contrived to receive and hold something.
As a tool, it is usually barrel-shaped with one open end to fit over a nut or bolt and the other open end with a female square drive to accept a drive tool (i.e., usually a ratchet).

Also See
Ball joint
Ball socket
Bayonet socket
Bihexagon socket
Cigar lighter
Diagnostic socket
Double hexagon socket
Impact socket
Insert socket
Lamp socket
Socket wrench
Spark plug socket
Spline Socket
T-handle socket
Universal joint socket
Universal spark plug socket

Socket bit: A bit for use with socket drive tools

Socket driver: A screwdriver-type handle for use with sockets

Socket Head: A recessed head in which the sides of the recess are parallel to the body axis, into which a wrench fits. The recess is commonly hexagonal or fluted in form. Also designated as internal wrenching head.

Socket head cap screw: Socket head cap screw

An externally threaded fastener with unified threads, a cylindrical head with a flat chamfered top surface, knurled cylindrical sides and hexagonal recess, made from alloy steel. Ideal for precision assembly work with close tolerances and applications needing a well tooled appearance.

Socket Head Shoulder Screw: Socket Head Shoulder Screw

A hex socket head screw with an enlarged, unthreaded, cylindrical shoulder under the head, the diameter of which serves as the basis for the derivation of the nominal size. For rotation or sliding applications, such as pulley shafts, in punch and die work, or for use as a bearing pin. Also called stripper bolt.

Socket joint: See
Ball and socket joint

Socket Set Screw: Socket Set Screw

A headless screw threaded the entire length. It has a hexagonal drive at one end. The other end will determine if it is a Cup point socket set screw, Half dog point socket set screw, Oval point socket set screw, Flat point socket set screw, or Cone point socket set screw.

Socket spanner: British term for Socket wrench

Socket wrench: A socket wrench is made up of a Ratchet and a variety of sockets. The ratchet end fits into the sockets. The end is usually one of three common sizes 0.25" (6.35 mm), 0.375" (9.5 mm), and 0.5" (13 mm). The socket (a cylinder) completely covers all the corners of the head of a bolt or nut. Some sockets have six faces while others have twelve.

Sock filter: A foam device which shaped like a cylinder with one end closed and the other open. The open end is secured to a carburetor so that the sock acts like a filter. It is used especially on snowmobiles to keep out the snow.

Sodium-cooled exhaust valve: The exhaust valves of some high-performance engines are filled with sodium to improve the heat dissipation from the valve stem to the valve guide, since the exhaust valve is subject to higher thermal loads than the intake valve

Sodium cooled valve: See
Sodium-cooled valve.

Sodium-cooled valve: An Exhaust valve with a hollow stem that is partially filled with metallic sodium. When the valve gets hot enough (138°C), the sodium melts and moves up and down in the Valve stem. The sodium absorbs heat from the hot Valve head and carries it away to the outer part of the stem and then into the Valve guide in the Cylinder head and next to the cylinder head itself. This circulation cools the valve head and thus the valve is allowed to run at a lower temperature.

Sodium Lamp: See
Low-Pressure Sodium Lamp

Sodium lights: A type of high intensity discharge light that has the most lumens per watt of any light source.

Sodium silicate: A grey-white powder soluble in alkali and water, insoluble in alcohol and acid. Used to fireproof textiles, in petroleum refining and corrugated paperboard manufacture, and as an egg preservative. Also referred to as liquid gas, silicate of soda, sodium metasilicate, soluble glass, and water glass.

Sodium-sulfur battery: A new type of battery, with higher energy density than conventional batteries such as the lead-acid battery; developed for use in electric powered vehicles

Sodium tripolyphosphate: A white powder used for water softening and as a food additive and texturizer.

Soft Code: See
Ignition-latched Soft Code

Softening agent: See
Plasticizer

Softening point: The temperature at which a known load will cause the bond failure of a one-square inch sample of cloth bonded to steel (sheer bond). Since softening under heat is progressive, increasing with temperature, it is rarely stated that a product is hard or soft at a certain temperature. The preferred method is to report what weight per square in ch area it can support without failure.

Softening temperature: See
Vicat softening temperature

Soft face hammer: A hammer with a head that is made of a material which will not damage the object being hit. It usually has replaceable screw-on faces made of plastic, nylon, or rubber

Soft paint: A paint fault apparent when the paint surface can be marked easily even after full drying has been allowed; caused by excessive film thickness or, in the case of two-pack paints, an insufficient quantity of catalyst

Soft pedal: The soft, springy feeling detected when the brake pedal is depressed and there is air present in the hydraulic system.

Soft-sided trailer: A trailer with canvas or other fabric walls, which folds compactly to the size and shape of a small trailer whose light weight and low profile result in low wind resistance and fuel consumption
Also see
Hard-sided trailer

Soft top: A convertible with a roof made of fabric rather than metal

Soft-top trailer: A camping trailer that has a solid box mounted on a chassis. The top portion is made of canvas and unfolds to create one or two wings

Soft trim: A vehicle's interior decoration, including the upholstery, roof, and door linings. Also called just trim.

SOHC: Acronym for single overhead camshaft where one cam operates both Intake and Exhaust valves.

Also See
Overhead camshaft
Engine type

Solar: See
Active Solar

Solar car: A lightweight electric vehicle powered by solar generators

Solar cell: Also known as a photovoltaic cell. Device which converts solar radiation directly to electricity.

Solar collector

A heat exchanger that transforms solar radiant energy into heat; typical solar collectors are flat-plate collectors and concentrating collectors
Device used to trap solar radiation, usually using an insulated black surface.

Also see
Unglazed Solar Collector

Solar constant: The average amount of solar radiation that reaches the earth's upper atmosphere on a surface perpendicular to the sun's rays; equal to 1353 Watts per square meter or 492 Btu per square foot.

Solar cooling: The use of solar thermal energy or solar electricity to power a cooling appliance. There are five basic types of solar cooling technologies: absorption cooling, which can use solar thermal energy to vaporize the refrigerant; desiccant cooling, which can use solar thermal energy to regenerate (dry) the desiccant; vapor compression cooling, which can use solar thermal energy to operate a Rankine-cycle heat engine; and evaporative coolers (swamp coolers), and heat-pumps and air conditioners that can by powered by solar photovoltaic systems.

Solar declination: The apparent angle of the sun north or south of the earth's equatorial plane. The earth's rotation on its axis causes a daily change in the declination.

Solar dish: See
Parabolic dish

Solar energy: The radiant energy of the sun, which can be converted into other forms of energy, such as heat or electricity.

Solar energy systems: Systems used to collect, convert, and distribute solar energy in forms useful within a business or residence. A passive system uses no additional energy from other sources for the distribution of the solar generated heat. An active system may use blowers, supplementary coils, etc.

Solar generator: A panel-shaped array of photovoltaic cells designed to transform solar radiant energy directly into electric energy; installed on car roofs, they can be used to recharge the batteries of electric-powered cars

Solar heat: Heat created by visible and invisible energy waves from the sun.

Solar Heating: See
Passive Solar Heating

Solar radiation: A general term for the visible and near visible (ultraviolet and near-infrared) electromagnetic radiation that is emitted by the sun. It has a spectral, or wavelength, distribution that corresponds to different energy levels; short wavelength radiation has a higher energy than long-wavelength radiation.

Solar spectrum: The total distribution of electromagnetic radiation emanating from the sun. The different regions of the solar spectrum are described by their wavelength range. The visible region extends from about 390 to 780 nanometers (a nanometer is one billionth of one meter). About 99 percent of solar radiation is contained in a wavelength region from 300 nm (ultraviolet) to 3,000 nm (near-infrared). The combined radiation in the wavelength region from 280 nm to 4,000 nm is called the broadband, or total, solar radiation.

Solar thermal collector: A device designed to receive solar radiation and convert it to thermal energy. Normally, a solar thermal collector includes a frame, glazing, and an absorber, together with appropriate insulation. The heat collected by the solar collector may be used immediately or stored for later use. Solar collectors are used for space heating; domestic hot water heating; and heating swimming pools, hot tubs, or spas.

Solar thermal panels: A system that actively concentrates thermal energy from the sun by means of solar collector panels. The panels typically consist of fat, sun-oriented boxes with transparent covers, containing water tubes of air baffles under a blackened heat absorbent panel. The energy is usually used for space heating, for water heating, and for heating swimming pools.

Solar thermal parabolic dishes: A solar thermal technology that uses a modular mirror system that approximates a parabola and incorporates two-axis tracking to focus the sunlight onto receivers located at the focal point of each dish. The mirror system typically is made from a number of mirror facets, either glass or polymer mirror, or can consist of a single stretched membrane using a polymer mirror. The concentrated sunlight may be used directly by a Stirling, Rankine, or Brayton cycle heat engine at the focal point of the receiver or to heat a working fluid that is piped to a central engine. The primary applications include remote electrification, water pumping, and grid-connected generation.

Solar trough: See
Parabolic trough

Solar parabolic trough: See
Parabolic trough

Solder

To join together using solder
A compound of two or more metals which have a relatively low melting point. Soft solder is an alloy of lead and tin while hard solder is an alloy of copper and zinc. With the application of heat, it is used to join wires or two pieces of metal together.

Also See
Braze
Brazing Solders
Flux
Hard Solder
Silver solder
Sweating
Tinning

Soldering: Joining two pieces of metal together with a lead-tin mixture. Both pieces of metal must be heated to insure proper Adhesion of the melted solder.
Also see
Silver solder.

Soldering flux: Substance applied to surfaces to be joined by brazing or soldering to keep oxides from forming and to produce joints.

Soldering iron: A tool with a handle attached to a copper or iron tip which is heated, electrically or in a flame, and used to melt solder to make joints

Solder joint: See
Cold solder joint

Solder paddle: A tool made of maple or beech, designed for spreading body solder over the surface of a panel

Solder paint: A paste used to prepare the area to be leaded so the body lead will stick to the metal surface; consists of a flux in which powdered lead is held in suspension

Solenoid

An electrically operated magnetic device used to operate some unit. A movable iron Core is placed inside a Coil of wire which moves because of magnetic attraction when electric Current is fed to the Coil. When Current flows through the Coil, the Core will attempt to center itself in the coil. In so doing, the Core will exert considerable force on anything it is connected to.
An electromagnetic valve or relay that opens or closes to regulate hydraulic pressure in an anti-lock brake system.

Also See
Air Core Solenoid
Bypass Air Solenoid
Canister Purge Solenoid
Clutch solenoid
Duty-cycle Solenoid
EGR Vent Solenoid
Fast idle solenoid
Idle stop solenoid
Mixture Control Solenoid
Purge Solenoid
Starter solenoid
Stop solenoid
Thermactor Air Bypass Solenoid
Thermactor Air Diverter Solenoid
Throttle solenoid
Throttle Stop Solenoid
Vacuum solenoid
Valve Solenoid

Solenoid starter switch: A solenoid-operated starter motor switch

Solenoid Vacuum Valve Assembly: See
Thermactor Air Control Solenoid Vacuum Valve Assembly

Solenoid valve

A valve actuated electrically by means of an electromagnet, or solenoid
Valve made to work by magnetic action through an electrically energized coil.
Electromagnet with a moving core. It serves as a valve or operates a valve.

Solenoid vent valve: (SVV) energized by ignition switch to control fuel vapor flow to the canister. When the ignition is off, the valve is open

Sole proprietorship: Business owned entirely by one person

Solid

Anything which does not have a tendency to flow (such as vapor or fluid).
Unventilated brake discs.

Also see
Bingham Solid
Industrial solid
Solids

Solid brake disc: A brake disc that is solid metal between its friction surfaces

Solid brake drum: A drum made entirely of cast iron.

Solid brake rotor: A rotor with solid metal between its friction surfaces.

Solid disc wheel: See
Plain disc wheel

Solid fuel heating: The use of solid natural resources such as wood or coal to provide heat.

Solid height: The height of a coil spring when it is totally compressed to the pont at which each coil touches the adjacent coil.

Solidity: To become solid, compact, or hard

Solid injection: System used in full diesel and semi-diesel where fuel in fluid state is injected into cylinder rather than a mixture of air and fuel drawn from a carburetor

Also See
Direct injection

Solid-mounted: A motorcycle with a solid-mounted engine bolted directly to the frame tubes.

Solid oxide fuel cell: (SOFC) A type of fuel cell in which the electrolyte is a solid, nonporous metal oxide, typically ZrO2 doped with Y2O3, and O2- is transported from the cathode to the anode. Any carbon monoxide (CO) in the Reformate gas is oxidized to carbon dioxide (CO₂) at the anode.

Solid paint: Paint of one uniform color, not metallic.

Solid phase pressure forming: A special type of thermoforming of polypropylene sheeting

Solid propellant: A propellant in pellet form, used to inflate air bags

Solid rivet: Solid rivet

A small metal fastener having no internal cavity, made of malleable material. Once the rivet is inserted in a hole, the free end is peened to secure it.

Solids

The ingredients (Pigments and Binders) of the paint that remain on the surface after the Solvents evaporate.
Industrial tires made without an air chamber.
Non-volatile ingredients in an adhesive, coating or sealer. Same as solids content.

Also see
Band Theory Of Solids
Volatile Solids

Solids in Bulk cargo: Truck that contains commodities that are not packaged, and are generally carried loose.

Solid state: Electronic device or assembly that does not have moving parts

Solid-state controlled ice maker: Includes controls for ice maker that uses components made of semiconductors.

Solid state controller: An electronic controller which uses transistors, diodes, and other semiconductor devices.

Solid-state electronic relays: See
Electronic relay

Solid-state ignition: See
Distributorless ignition system

Solid state ignition system: (SSI) a system used by Ford

Solid tire: A solid rubber tire that is not inflated by air. The opposite is Pneumatic tire. Solid tires are used on slow-moving wheels (i.e., wheelchairs, buggies, children's wagons, etc.).
Also see
Separation solid tire

Solo seat: A motorcycle saddle designed for just the operator.

Soluble: Matter or compounds capable of dissolving into a solution.

Soluble anode: Positive electrode of a galvanic cell at which metal ions pass into solution

Soluble Organic Fraction: (SOF) The organic fraction of diesel particulates. SOF includes heavy hydrocarbons derived from the fuel and from the engine lubricating oil. The term soluble originates from the analytical method used to measure SOF which is based on extraction of particulate matter samples using organic solvents.

Solution

A single, homogeneous liquid, solid, or gas phase that is a mixture in which the components (liquid, gas, solid, or combination thereof) are distributed uniformly.
A liquid which has another liquid or solid completely dissolved in it. A lithium bromide water solution, commonly used in absorption Systems, is water with a quantity of lithium bromide dissolved in it. 'Strong" and weak solutions are those with respectively high and low concentrations of another liquid or solid.

Also See
Phosphating solution

Solution annealed: A process of heating and removing carbide precipitants (carbon that has broken loose from its stainless steel solution) by heating a finished fastener to over 1000°C and cooling it quickly, usually in water, so carbon content goes back into the stainless solution. Also called carbide solution annealed

Solution pressure: A measure of the tendency of hydrogen, metals, and certain non-metals to pass into solution as ions

Solvent

A fluid that dilutes, liquefies, or dilutes another liquid or solid. Solvents include Thinners, Reducers and cleaners. Examples Alcohol thins shellac; Gasoline dissolves grease.
Any liquid which will dissolve another substance. The solvent power of a liquid is specific; that is, it will dissolve some substances but not others. Solvents are often of a volatile nature and do not remain in a set or cured adhesive, coating, or sealer film. Their main purpose in adhesives, coatings, or sealers is to convert the solid portion into a more fluid state so that it can be easily applied.

Also see
Reactivation Solvent

Solvent pop: Small bumps in a paint film which, under close inspection, can be seen to have small holes in the top; caused by excessive film depth being applied in one coat, preventing the thinners from escaping properly

Solvent popping: Blister that form on the paint film, caused by trapped solvents

Solvent reactivation: To restore the surface tackiness in a dry adhesive film with a suitable solvent.

Solvent resistance: Ability of an adhesive, coating, or sealer to withstand total immersion in a given solution without losing its original properties.

Sone

Calculated sound loudness rating.
A measurement of the noise level of a fan. The lower the sone rating, the lower the noise level.

Sonic idling: A system developed by Ford, for a fixed jet carburetor which uses air at the speed of sound to atomize fuel supplied by the idling circuit; makes idling smoother and reduces exhaust pollution. Also called sonic throttling

Sonic throttling: A system developed by Ford, for a fixed jet carburetor which uses air at the speed of sound to atomize fuel supplied by the idling circuit; makes idling smoother and reduces exhaust pollution. Also called sonic idling

Sonoscope: A diagnostic tool used to listen for noises in engines and identify trouble spots such as faulty valves, worn gears and water pump, bearing knock, damaged gaskets, or piston slap. Also called a Mechanic's stethoscope

Sooted plug: A carbon-fouled spark plug

Sooty plug: A carbon-fouled spark plug

Sounding pipe: A pipe leading to the bottom of an oil or water tank, for guiding a sounding tape or jointed rod when measuring the depth of liquid in the tank

Sound absorption: The weight and space restrictions of modern cars call for sound absorption using thin-walled materials, whose thickness is small in relation to the wave length of the sound to be absorbed

Sound level: The sound pressure level (in decibels) at a point in a sound field, averaged over the audible frequency range and over a time interval, with a frequency weighting and time interval specified by the American National Standard Association.

Sound metal: An intact metal panel not substantially weakened by rust that provides a basis, for example, for welding on repair panels

Soundproofing material: Any material used to deaden the sound from surfaces which transmit or generate noise; (e.g., felt lining on the underside of a hood).
Also see
Anti-drum compound

Sound tracer: Instrument which helps locate sources of sound.

Sound walls: Concrete block or concrete panel walls specifically designed to reduce road sounds outside of the right-of-way.

Souped up: A vehicle is souped up when it is tuned to produce the maximum amount of power.

Souping: Hopping up or increasing engine performance through various modifications.

Source: See
Energy Source
Office Of Mobile Sources

Source lamp: See
Linear source lamp

Source Leasing: See
Single-Source Leasing

Sour gas: Natural gas that contains hydrogen sulfide (H₂S). Contrast Sweet gas

South pole: The magnetic pole in a Magnet toward which the lines of force emanate; travel is from North to South pole.
Also see
Magnetic South Pole

South pole, magnetic: The part of a magnet into which magnetic flux lines flow.

SO_x: Symbol for oxides of sulfur