DICTIONARY OF AUTOMOTIVE TERMS - "La"

L:

1. Low gear in an automatic transmission.
2. Designation for luxury or luxe

l/100 km:

This is the metric measurement of fuel consumption or fuel economy. The lower the number the more economical the vehicle. Thus a vehicle that gives 7 l/100 km is better than one that gives 8 l/100 km. A vehicle that gives 7.3 l/100 km is giving 32.2 mpg US and 38.7 mpg Imperial.

LAADA:

Acronym for "Latvian Authorized Automobile Dealers Association."

Labelling Act:

See American Automobile Labelling Act

Labour:

An engine which is struggling to keep turning due to lack of revs or the use of too high a gear

Labouring:

A British term for "lugging" which indicates an engine having difficulty in turning.

Lack of parallelism:

A measurement of brake rotor thickness variation at various points around a rotor.

Lacquer:

1. A fast drying automotive body pyroxylin paint.
2. A glossy coating made by dissolving cellulose derivatives in a rapidly evaporating solvent.
3. Protective coating or finish which dries to form a film by evaporation of a volatile (easily goes from liquid to gas) constituent.

Also See:
clear lacquer
general purpose lacquer thinner

Lacquer thinner:

See general purpose lacquer thinner

Ladder bars:

A rigid triangular suspension devices used to locate an axle front to rear. These are used almost exclusively in drag race cars due to the fact that they bind when cornering. A panhard rod or a watts link is used to locate the axle side to side.

Ladder chassis:

See ladder frame

Ladder diagram:

Electrical diagram that indicates order of electrical devices in a specific electrical circuit.

Ladder frame:

A type of frame design which has two long parallel sections which run from the front to the rear of the vehicle. In various places there are shorter sections which connect the long sections. The result looks like a ladder. The connecting pieces hold various components such as the engine. This design is not used today because it is too heavy and lacks rigidity. Also called "ladder chassis"

Laden weight:

See gross vehicle weight.

Lading:

The load or freight that a vehicle carries.
Also See:
bill of lading

Ladies' frame:

The type of frame in which the top tube is replaced by a second down tube to make mounting and dismounting the bike easier.

Lag:

Delay in response.
Also See:
ignition lag
lead and lag
turbo lag

Lago:

See talbot Lago

Lagonda:

A vehicle brand of which all 1925-48 models except Rapier are classic cars. See the 1938 Lagonda. The 1948-49 V-12 models are milestone cars.

Lagonda Drophead:

A vehicle brand of which the 1949-53 2.5 Liter Drophead Coupes are milestone cars.

Lake pipes:

Nonfunctional side pipes attached along the lower sides of a vehicle for decorative purposes only. Also called "Lakes pipes" or "lakers"

Laker:

A type of ship which trades only in the Great Lakes of North America. The cargo is usually grain and ore.

Lakers:

Nonfunctional side pipes attached along the lower sides of a vehicle for decorative purposes only. Also called "lake pipes" or "Lakes pipes"

Lakes pipes:

Nonfunctional side pipes attached along the lower sides of a vehicle for decorative purposes only. Also called "lake pipes" or "lakers"

Lakes ship:

See Great Lakes ship

Lambda:

1. Eleventh letter of the Greek alphabet. In upper case it looks like "A" without the cross bar. In lower case it looks like an up-side-down "y".
2. Bosch's term for oxygen

Lambda control:

Bosch's term for a closed loop system that adjusts the air-fuel ratio to lambda-1, based on sensing the amount of excess oxygen in the exhaust

Lambda control valve:

See frequency valve

Lambda probe:

See oxygen sensor

Lambda sensor:

See oxygen sensor

Lambda valve:

In Bosch CIS, a device that regulates pressure in the lower chamber of the differential-pressure valve, in response to a signal from the lambda (oxygen) sensor. Also called frequency valve or a timing valve

Lambda window:

A narrow range (where lambda = 1), which yields the lowest emission values for CO, NO_x, and HC

Lamborghini:

A model of automobile manufactured in Italy
Click image for books on Lamborghini

Laminate:

1. To build up or construct out of a number of thin sheets which are bonded together. The magnetocoil has a laminated core.
2. A sheet of material made of several different bonded layers.
   Also See:
   sandwich laminate

Laminated:

Something made up of many layers.

Laminated glass:

A sandwich-type construction of two or more panes of glass laminated together with an extremely tough, crystal-clear plastic film; on severe impact, laminated glass will crack, but not shatter like ordinary glass, nor craze over like toughened glass

Laminated iron core:

The core of an ignition coil consisting of pieces of soft iron laminations, insulated from one another

Laminated windshield:

Older safety windshields were made of tempered glass which is heat treated so that the surface is very tough. When a vehicle with tempered glass is involved in an accident, the windshield shatters into a spider web of little crystals. Its adhesive property is greatly diminished so that an object (your body) can easily be ejected through the windshield. Laminated windshields, however, are made with two sheets of glass with a thin layer of rubbery plastic in between. When your head hits the windshield, the windshield bows out without being punctured. The plastic sandwich prevents the glass from splintering. The "plastic sandwich" can also contain a tint to reduce heat in the passenger compartment and protect the eyes from glare (like sunglasses). Compare toughened windshield

Laminated windshield glass:

See laminated windshield.

Laminating:

Covering sheets with a particular layer or covering molded parts with a specific plastic film

Lamination:

1. The act of laminating. The process of bonding two or more layers or plies of material together with an adhesive
2. A thin layer.
3. A structure made up of thin layers

Lamp:

A device for giving off light without being consumed itself.
Also See:
auxilliar driving lamp
blowlamp
clearance lamp
dome lamp
driving lamp
fog lamp
gas discharge lamp
gaseous discharge lamp
headlight
headlight retractor indicator lamp
inspection lamp
linear lamp
linear source lamp
marker lamp
numberplate lamp
parking lamp
puddle lamp
rear fog lamp
rear lamp cluster
rear license plate lamp
repeater lamp
side marker lamp
spot lamp
strobe lamp
tail lamp
test lamp
warning lamp

Lamp aperture:

An opening in a sheet metal panel for mounting the headlight or taillight

Lamp blackening:

The blackening of a light bulb; gradual blackening of conventional, i.e., non-halogen light bulbs, occurs as a result of metal vapor deposition on the glass envelope which reduces light emission; severe blackening indicates imminent bulb failure

Lamp cluster:

A group of lights behind a cover; the rear lights of most cars are grouped together in clusters.
Also See:
rear lamp cluster

Lamp panel:

A panel that encloses part or all of the headlight or taillight cutout and may extend across the width of the car to include both cutouts; in the latter case, it forms an additional panel to be joined to the smaller front or rear valances

Lamp socket:

A device which holds a light bulb and provides electricity to the bulb. The British term is bulb holder

Lamp, steri:

Lamp which has a high-intensity ultraviolet ray used to kill bacteria. Also used in food storage cabinets and in air ducts.

Lamp unit:

A sealed light unit with reflector and lens all-in-one

Lanchester:

A vehicle brand of which the 1925-1948 models with required application are classic cars.

Lancia:

A vehicle brand of which the 1925-1948 models with required application are classic cars. The 1959-64 Flaminia Zagato models are milestone cars. The 1961-63 Flaminia GT Two Passenger Coupe or Convertible are milestone cars. The 1962-66 Flavia Coupe are milestone cars. The 1951-59 Aurelia B.20 and B.2O Coupe are milestone cars. The 1953-59 Aurelia B.24 Spyder and Convertible are milestone cars.
Click image for books on Lancia

Lancing:

See wax lancing

Land:

The smooth, open area of a grooved surface, such as the bands of metal between the grooves in a piston which carry the piston rings. The metal separating a series of grooves.
Also See:
head land
piston lands
top land

Landau:

A closed-type body on the sides, it has provision for opening or folding the fabric top over the rear quarter. This precludes the use of rear quarter windows. Landau irons are fairly common but not a mandatory feature.

Landau bar:

See landau bars.

Landau bars:

S-shaped bars or irons on the C-post. On convertibles, they are functional; but decorative on other body styles.

Landaulet:

A classic car style characterized by the fact that only the rear seats were protected by a hard or convertible top, whereas the driver was exposed to the open air in order to be more aware of road and weather conditions; an imitation landaulet style is still found on some American sedans. Also called landau

Landaulet sedan:

This body style is similar to the landau sedan in appearance, but with a stationary rear quarter. Landau irons are mounted on the rear quarter but are non-functional.

Landing:

See hood landing panel

Landing panel:

See:
bonnet landing panel
hood landing panel

Landing section:

See fender landing section

Landline:

Trucker slang for Telephone as in "It is hard to find a landline when you need one."

Land management:

See bureau of land management

Land Rover:

An SUV built in England
Click image for books on Land Rover

Lands:

The piston metal between the ring grooves. See piston lands.

Lane:

1. A narrow road, often in the country.
2. A track on a road, defining lines of traffic.

Also See:
crawler lane
fast lane
passing lane
splitting lanes

Lane splitting:

Riding between lanes of traffic on a freeway

Lantern-type jacket tube:

See Japanese lantern-type jacket tube

Lanyard:

A line (made of rope, nylon, etc.) which is attached at one end to a frame or large item while the other end is attached to a smaller piece that might get lost. The picture shows a lanyard attached to a hitch pin.

Lap:

1. One complete trip around a race track or route laid out for racing.
2. To fit two surfaces together by coating them with abrasive and then rubbing them together (e.g., to lap valves into valve seats).
3. The upper surface of the human body from waist to knees when seated.
4. A rotating disc covered with fine abrasive for polishing.

Also See:
pace lap
turn a lap

Lap belt:

A 2-point belt pulled across the hips, or lap belt portion of a combined lap/shoulder belt; mostly only on the rear center seat, on some models on all rear seats. See submarining

Lap joint:

1. A piston ring gap in which the two ends of the ring are shaped like the letter "L".
2. A welding term describing a union in which the edges of the two metals to be joined overlap one another.

Lapper:

See valve lapper

Lapping:

Smoothing a metal surface to high degree of refinement or accuracy using a fine abrasive.

Lapping compound:

See valve lapping compound

LaSalle:

A vehicle brand of which the 1927-1933 models are classic cars.

Lash:

1. The amount of free motion between two components (e.g., two gears). The British term is "free play."
   Also See:
   backlash
   valvelash
   whiplash
2. Acronym for "Lighter Aboard Ship": a ship designed to carry floating containers or lighters.

Last station memory:

An audio and video term describing the circuit which ensures that when the unit is turned on, the tuner automatically tunes to the station that was received before the unit was turned off

Latch:

A fastening device for a door or panel. It consists of a small metal bar, either mounted on the movable part (always on doors and on some tailgates), or on the car body (always on hoods and trunks), which engages with a striker on the opposite part.
Also See:
door latch

Latching pillar:

See B-pillar

Latch pillar:

See B-pillar

Late braking:

Braking later into the turn, thus moving the entry point and axis of the vehicle

Latent heat:

The heat absorbed or radiated during a change of state (i.e., melting, vaporization, fusion) at constant temperature and pressure. Called latent cause it is hidden -- cannot be felt or measured with a thermometer

Latent heat of condensation:

The amount of heat given off when a substance changes from a vapor to the liquid without changing temperature

Latent heat of evaporation:

The amount of heat required to change a liquid into a vapor without raising the temperature of the vapor above that of the original liquid

Latent heat of vaporization:

Amount of heat required, per pound of substance, to change its state from a liquid to a vapor (gas).

Lateral:

Relating to the side.

Lateral acceleration:

The acceleration created when a vehicle corners that tends to push a vehicle sideways. Because of centrifugal force, the vehicle is pushed outward. For this reason, you need to accelerate a little as you reach the apex of the curve to pull you through the curve. An inexperienced driver may panic in a curve as the lateral acceleration pushes his vehicle into the left lane. He might hit the brakes to slow the motion only to find that the problem actually increases. The proper way to take a sharp corner is to slow down before the curve, then accelerate at the apex of it to bring the vehicle around. To increase your frustration, try following an inexperience driver as he drives on mountain roads. He maintains his speed to the corner and brakes at the apex.
Also See:
acceleration

Lateral acceleration sensor:

A device that signals the ECU when the vehicle is being subjected to high g-force from a turn; the signal voltage varies according to the amount of g-force

Lateral acceleration switch:

Similar to a lateral acceleration sensor, but the switch provides a simple on-off signal, rather than the variable voltage signal provided by the sensor

Lateral air passage:

A passage at the nozzle of a spray gun for shaping the spray pattern to a long or elongated oval

Lateral arm:

A suspension member connecting the upright to the chassis. See transverse arm.

Lateral atomization orifice:

An additional passages at the nozzle of a spray gun for supplying additional air to break up the paint into smaller droplets

Lateral clearance:

The smallest distance laterally between the tire and the nearest fixed point of the vehicle.

Lateral grip:

The ability of a tire to maintain its course, or remain under normal steering control, while being subjected to directionally disturbing influences

Lateral impact:

A side crash

Lateral link:

A suspension link that is aligned to resist sideways motions in a wheel.

Lateral run-out:

1. Amount of side (i.e., side-to-side) movement of a rotating wheel, tire, or the rotor from the vertical.
2. A tire assembly that does not run true to its plane; i.e., a damaged wheel moving in a wobbling, side to side manner.
3. A measurement of the lateral change in position of the disk-brake-rotor surface during one revolution.

Lateral runout:

See lateral run-out

Lateral stability:

Limiting side movement. (1) Tread grooves running circumferentially around the tire resist side forces for maximum traction on sums. (2) Stabilizing tread plies limit side to side movement of the tread ribs caused by the expansion and contraction of tread areas as sidewalls flex. Also called lateral grip

Lateral stiffness:

The resistance of a vehicle body structure to lateral impact

Lateral tire clearance:

The distance between the tire sidewall and the nearest point on the vehicle, reduced by any increase in rim offset and 1/2 any increase in tire section from the existing tire.

Latex tube:

An bicycle inner tube for tires because of its lighter weight. Can be hard to repair, must be reinflated for each ride.

Lathe:

A device for shaving the metal from the outside or inside of a cylinder.
Also See:
brake drum lathe

Lathe-cut:

A process of cutting rubber seals to a precise shape on a rotating drum.

Law:

See:
Newton's law
Pascal's law

Lay-by:

A British term for a "rest stop," i.e., a place at the side of a road where drivers can stop (to rest)

Layer:

A certain weld metal thickness made of one or more passes.
Also See:
anodic oxide layer
catalytic layer
gamma layer
zinc-iron alloy layer

Layer of pure zinc:

The top layer on hot-dip galvanized steel which, in contrast to zinc-iron alloy layers, almost completely consists of zinc

Layer thickness:

A coating thickness (indicated in micrometers or millimeters)

Laying the bike down:

A crash where you slide down on one side of the bike

Laying up:

The process of adding several layers of fibreglass mat and resin to form a GRP shell

Layout:

See:
drive layout
east-west layout
engine layout
north-south layout

Layrub coupling:

A universal joint using four molded rubber inserts mounted on a round steel plate

Layshaft:

A British term for a countershaft -- the intermediate shaft between and parallel to the input and output shafts, carrying the two pairs of gearwheels which provide the required changes in gear ratio

Lay-up resin:

The resin substance used to laminate GRP parts. The resin available on the do-it-yourself market for fibreglass mat repairs also belongs to this category

Lazy tongs:

1. Any device with extensible arms (often in the form of a series of crossed, hinged bars) for handling objects at a distance.
2. A specific type of pop rivet gun with such arms

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