Dictionary of Automotive Terms: G

GAL: Gallon.

GALVANOMETER: Instrument used to measure pressure, amount of, and direction - of an electric current.

GAS: A nonsolid material. It can be com pressed. When heated, it will expand and when cooled, it will contract. (Such as air.)

GAS BURNER or GASSER. Competition car with engine set up to operate on standard pump gasoline instead of an alcohol, nitro, etc., mixture.

GASKET: Material placed between two parts to insure proper sealing.

GASOHOL: Automotive engine fuel made up of around 90 percent gasoline and 10 per cent ethanol alcohol.

GASOLINE: Hydrocarbon fuel used in the internal combustion engine.

GASSING: Small hydrogen bubbles rising to top of battery electrolyte during battery charging.

GAWR: See Gross Axle Weight Rating.

GEAR: Circular object, usually flat edged or cone-shaped, upon which a series of teeth have been cut. These are meshed with teeth of another gear and when one turns, it also drives the other.

GEAR RATIO: Relationship between number of turns made by driving gear to complete one full turn of driven gear. If driving gear turns four times to turn driven gear once, gear ratio would be 4 to 1.

GENERATOR: Electromagnetic device for producing electricity.

GENERATOR REGULATOR: See Regulator.

GLASS: Term used for the material “fiber glass.”

GLASS PACK MUFFLER: Straight through (no baffles) muffler utilizing fiberglass packing around perforated pipe to deaden exhaust sound.

GLAZE: Highly smooth, glassy finish on cylinder walls.

GLAZE BREAKER or DEGLAZER: Abrasive tool used to remove glaze from cylinder walls prior to installation of new piston rings.

GLOW PLUG: A heating device placed in a diesel engine pre-combustion chamber to facilitate cold engine starting. When engine is cold, an electric current is passed through plug causing it to glow red hot. This helps ignite compressed fuel.

GMC: General Motors Corporation.

GOVERNOR: Device designed to automatically control speed or position of some part.

GPM: Gallons Per Minute.

GRADIENT: Angle of hill. A 20 percent gradient would be a hill that would rise two feet for every ten forward feet of travel. This is determined by rise as a percentage of for ward travel.

GRID: Lead screen or plate to which battery plate active material is affixed.

GRIND: To remove metal from an object by means of revolving abrasive wheel, disc or belt.

GROSS AXLE WEIGHT RATING: Total load carrying capacity of a given axle (front or back) setup. Weight rating can be ex pressed as rating at springs (total load on springs) or at ground (total load measured where tire meets ground). Weight at ground rating includes weight of tires, wheels, axle, and springs.

GROUND ( Battery): Terminal of battery connected to metal framework of car. In this country, NEGATIVE terminal is grounded.

GROWLER: Instrument used in testing starter and generator armature.

GUDGEON PIN: British term for piston or wrist pin.

GUM (Fuel system): Oxidized portions of fuel that form deposits in fuel system or engine parts.

GUSSET: A metal piece, usually of flat plate, used to strengthen a joint between two parts such as frame rails. Usually welded or riveted into place.

GUT: To strip the interior of car. May also refer to removing internal baffles from muffler.

GVW: Gross Vehicle Weight. Total weight of vehicle including vehicle passengers, load, etc. Used as indicator of how heavy vehicle can be loaded (GVW minus vehicle curb weight = payload).

GVWR: Gross Vehicle Weight Rating. See GVW.