DICTIONARY OF AUTOMOTIVE TERMS - "Cl"

CL
  1. Acronym for Comfort Luxe as a designation for a vehicle which is more luxurious than an L but not quite as luxurious as a GL
  2. Acronym for Closed Loop
Cladding
  1. A process of covering one material with another and gluing them together under high pressure and temperature.
  2. The outer body panels which are attached to the vehicle's frame.
  3. Excessive decorative elements applied to a vehicle.
Claim
  1. A demand for reimbursement made by the customer for freight that is lost and/or damaged.
  2. A demand made by the customer for a refund on overcharge on transportation bill
  3. A demand made by an individual or company to recover loss under insurance policy.
Claire

See
Wills Sainte Claire

Clamp
A fastening device which secures something within its jaws without constant human pressure.

Also See
Anchor Clamp
Bar clamp
Battery clamp
C-clamp
Cable clamp
Cheney Clamp
Distributor hold-down clamp
G-clamp
Hose clamp
Hose clamp installer
Hose clamp pliers
Jubilee Clamp
Locking bar clamp
Locking clamp
Long-reach C-clamp
Piston ring clamp
Screw Clamp
Sheet metal clamp
Triple clamp
V-band clamp
Welding clamp
Wheel clamp

Clamping load
In a clutch, the amount of pressure on the plates.
Clamp installer

See
Hose clamp installer

Clamp on

See
Front Derailleur Clamp on

Clamp pliers

See
Hose clamp pliers

Clamshell
A shape which has a bottom and top but is hinged at one end so that it can be opened to expose its interior.
Clapboard
A narrow board which is thicker at one edge than the other edge and used to protect from the weather.
Clarifier
A machine used for a liquid-sludge separation in which the particles with a higher specific gravity are separated from the lower specific gravity of the liquid. A clarifier bowl has one outlet for the light phase oil; the heavier phase particles are retained on the bowl wall.
Clark
Clark, Jim -- Winner of 3 Formula One Championships, 25 Grand Prix races and of the 1965 Indianapolis 500
Class 1 driver's license
class1

Semi-trailer truck

In Canada, a driver's license which permits driving semi-trailer trucks and all other motor vehicles or combinations of vehicles except motorcycles
Class 1 motor carrier
A U.S. classification of a common or contract motor carrier with annual gross revenues of five million dollars or more.
Class 1 road
Hard surface highways including interstates and U.S. numbered highways (including alternates), primary state routes and all controlled access highways.
Class 2 driver's license
class 2

Class 2

In Canada, a driver's license which permits driving the following
  1. Buses, including school buses, special activity buses and special vehicles
  2. Trailers or towed vehicles that do not exceed 4,600 kilograms except if the bus and trailers or towed vehicles do not have air brakes
  3. Any motor vehicle or combination of vehicles in Class 4

Class 2 road
Hard surface highways including secondary state routes, primary county routes and other highways that connect principle cities and towns, and link these places with the primary highway system.
Class 3 driver's license
class 3

Class 3

In Canada, a driver's license which permits operating the following
  1. Trucks with more than two axles, such as dump trucks and large tow trucks, but not including a bus that is being used to transport passengers
  2. Trailers that do not exceed 4,600 kilograms except if the truck and trailers do not have air brakes
  3. A tow car towing a vehicle of any weight
  4. A mobile truck crane
  5. Any motor vehicle or combination of vehicles in Class 5
Class 3 road
Hard surface roads not included in a higher class and improved, loose surface roads passable in all kinds of weather. These roads are adjunct to the primary and secondary highway systems. Also included are important private roads such as main logging or industrial roads that serve as connecting links to the regular road network.
Class 4 driver's license
class 4

Class 4

In Canada, there are two types of Class 4 driver's license unrestricted and restricted The unrestricted Class 4 allows driving the following
  1. Buses with a maximum seating capacity of 25 persons (including the driver), including school buses, special activity buses and special vehicles used to transport people with disabilities
  2. Taxis and limousines
  3. Ambulances
  4. Any motor vehicle or combination of vehicles in Class 5
class 4

Class 4

The restricted Class 4 allows driving the following
  1. Taxis and limousines (up to 10 persons including the driver)
  2. Ambulances
  3. Special vehicles with a seating capacity of not more than 10 persons (including the driver) used to transport people with disabilities
  4. Any motor vehicle or combination of vehicles in Class 5
Class 4 road
Unimproved roads that are generally passable only in fair weather and used mostly for local traffic. Also included are driveways, regardless of construction.
Class 5 driver's license
class 5

Class 5

In Canada, a driver's license which permits operating the following
  1. Two axle vehicles including cars, vans, trucks and tow trucks
  2. Trailers or towed vehicles may not exceed 4,600 kilograms
  3. Motor homes (including those with more than two axles)
  4. Limited speed motorcycles or moped (in some provinces, a Class 8 is required to operate these) and all-terrain vehicles (ATVs)
  5. Passenger vehicles used as school buses with seating capacity of not more than 10 persons (including the driver)
  6. Construction vehicles
  7. Three-wheeled vehicles - does not include three-wheeled motorcycles (trikes) or motorcycle/sidecar combinations
  8. Does not include Class 4 vehicles or motorcycles
Class 5 road
Unimproved roads passable only with 4-wheel drive vehicles.
Class 6 driver's license
class 6

Class 6

In Canada, a driver's license which permits operating the following
  1. Motorcycles, all-terrain cycles, all-terrain vehicles (ATVs)

Class 7 driver's license
class 5

Class 7

In Canada, a learner's driver's license which permits operating the following
  1. Two axle vehicles including cars, vans, trucks and tow trucks
  2. Trailers or towed vehicles may not exceed 4,600 kilograms
  3. Motor homes (including those with more than two axles)
  4. Limited speed motorcycles and all-terrain vehicles (ATVs)
  5. Passenger vehicles used as school buses with seating capacity of not more than 10 persons (including the driver)
  6. Construction vehicles
  7. Three-wheeled vehicles - does not include three-wheeled motorcycles (trikes) or motorcycle/sidecar combinations
  8. Does not include Class 4 vehicles or motorcycles
Class 8 driver's license
moped

Moped

In some provinces of Canada, a driver's license which permits operating a moped or limited speed motorcycles
Class 9 driver's license
class 9

Class 9

In some provinces of Canada, a driver's license which permits operating a farm tractor
Class A driver's license
class 1

Class 1

  1. In some provinces of Canada, a driver's license which permits operating
    1. Any tractor-trailer or combination of motor vehicle and towed vehicles where the towed vehicles exceed a total gross weight of 4,600 kilograms
    2. Any motor vehicle pulling double trailers
    3. Any motor vehicle pulling a trailer with air-brakes
    4. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
  2. A class A with restrictions prevents operating
    1. a motor vehicle pulling double trailers
    2. a motor vehicle pulling a trailer with air-brakes

Class A RV
class A RV

Class A RV

class A RV

Class A RV

The Class A is the largest and usually most luxurious motorhome. They are frequently constructed on custom undercarriages or on a 3-10 ton truck chassis. Many also feature an automatic slideout so that at the touch of a button, a portion of the RV exterior wall can extend outward to expand living space. Most models offer complete self-containment, with on-board generator, large water and holding tanks, big batteries and a generous propane supply. They usually provide cooking facilities, a refrigerator, heating, air conditioning, a self-contained toilet, water tanks (fresh water, grey water, black water), faucets, sinks, a LP (propane) gas supply, a separate 100-125 volt electrical system, and a full array of appliances and entertainment features. They are especially good for dry camping (without hookups), even for extended periods. They can sleep up to eight people, depending on the model and the floor plan. Prices range from $80,000 to above $700,000 for high end rear diesel models.
Class A thread
A British term for external thread.
Class B driver's license
class B

Class B

In some provinces of Canada, a driver's license which permits operating the following
  1. Any school purposes bus with designed seating capacity for more than 24 passengers
  2. Any regular bus with designed seating capacity for more than 24 passengers
  3. Any truck or motor vehicle combination exceeding 11,000 kg provided the towed vehicle is not over 4,600 kg
  4. School purposes bus - maximum of 24 passenger capacity
  5. Regular bus maximum of 24 passenger capacity and ambulances
  6. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class B RV
class B RV

Class B RV

A small motorhome usually called a van conversion or camping van conversion. The basic Class B RV is built on an ordinary van chassis which retains the original dimensions of the van but features a raised roof (usually fiberglass) in order to allow full standing headroom. They also include a small galley (cooking facility, refrigerator, heater, fresh water tank, waste water tank, faucet, sink), a LP (propane) gas supply, 110 Volt AC and 12 Volt DC electrical outlets, and portable toilet. They can sleep from two to four people.
Class B thread
A British term for internal thread.
Class C driver's license
class C

Class C

In some provinces of Canada, a driver's license which permits operating the following
  1. Any regular bus with designed seating capacity for more than 24 passengers
  2. Regular bus maximum of 24 passenger capacity and ambulances
  3. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class C RV
class C RV

Class C RV

class C RV

Class C RV

A recreational vehicle (also called a mini-motorhome) built on a van chassis that has been cut just behind the cab (the driver's section) so that a camping unit can be attached to the rear. Generally these units are easier to drive than a Class A motorhome. They are generally constructed on a larger van chassis. The driver compartment is similar to a van, with a large box in the back. Class C motorhomes usually come with a sleeping bunk above the cab, in addition to a bedroom in the rear of the unit. Like their Class A big brothers, many Class C units feature a slideout to quickly extend the motorhome's living space. Class C units usually provide cooking facilities, a refrigerator, heating, air conditioning, a self-contained toilet, water tanks (fresh water, grey water, black water), faucets, sinks, a LP (propane) gas supply, a separate 100-125 volt electrical system, and a full array of appliances and entertainment features. Class C motorhomes can sleep up to ten people depending on the model and the floor plan.
Class D driver's license
class D

Class D

In some provinces of Canada, a driver's license which permits operating the following
  1. Any truck or motor vehicle combination exceeding 11,000 kg provided the towed vehicle is not over 4,600 kg
  2. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class E driver's license
class E

Class E

In some provinces of Canada, a driver's license which permits operating the following
  1. School purposes bus - maximum of 24 passenger capacity
  2. Regular bus maximum of 24 passenger capacity and ambulances
  3. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class F driver's license
class F

Class F

In some provinces of Canada, a driver's license which permits operating the following
  1. Regular bus maximum of 24 passenger capacity and ambulances
  2. Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class G driver's license
class G

Class G

In some provinces of Canada, a driver's license which permits operating any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
Classic car
  1. An older vehicle that is generally considered to be one of the finest models ever built. As used by the average person, an older vehicle in original (like-new) shape or has been restored with some modern refinements (e.g., special wheels, improved seating, modified engine, 12-volt electricals, etc.)
  2. A vehicle (including hardtop or convertible) built during 1950-1973 and in original form with no modern technology, equipment, or refinements except wheels.
  3. A vehicle defined by the Classic Car Club of America built during the years 1925-1948. They include the following:
The items marked with an asterisk (*) indicate that these models require application to be considered a classic car.

Also see
antique car
collectible car
late model car
milestone car
modified car
muscle car
street rod
vintage car

Classic Car Club of America
(CCCA) Organization which defines which cars are true classics. 1645 Des Plaines River Road, Suite 7A, Des Plaines, IL, 60018-2206, ph 847.390.0443
Classification

See
Automobile Classification
Bridge Classification
Standard Industrial Classification
Truck Classification

Classification society
Independent and reputable organizations which verifies and inspects vessels for seaworthiness. As technical experts, they serve to provide the necessary basis for adjusting insurance rates for the vessel.
Classification System

See
North American Industrial Classification System

Class II

See
Hitch Class II

Class M driver's license
class M

Class M

In some provinces of Canada, a driver's license which permits operating one or more of the following
  1. Motorcycles
  2. limited-speed motorcycle (motor scooter)
  3. motor-assisted bicycle (moped)

Class of Thread
Threads differ by the amount of tolerance or tolerance and allowance specified. Classes 1A, 2A, and 3A apply to external threads, and Classes 1B, 2B and 3B apply to internal threads.
Class rate
A shipping term for the fees charged for commodities grouped according to similar shipping characteristics.
Claw hammer
claw hammer

Claw Hammer

A hammer with a forked end on the head which is used for removing nails.
Claxton horn
A Horn which makes a particular sound Ah-oo-gah.

Also See
Horn


Clay model
When the design department is creating a new model, it will be built in clay to full size to determine its looks etc.
CLC
Acronym for Converter Lockup Clutch--replaced by TCC
CLCC
Acronym for Closed Loop Carburetor Control
Clean

See
Steam clean

Clean Air Act
(CAA) In the U.S., the fundamental legislation to control air pollution. The original Clean Air Act was signed in 1963. The law set emissions standards for stationary sources, such as factories and power plants. Criteria pollutants included lead, ozone, CO, SO2, NOx and PM, as well as air toxics. The CAA was amended several times, most recently in 1990 (P.L. 101-549). The Amendments of 1970 introduced motor vehicle emission standards for automobiles and trucks. In 1990, reformulated gasoline (RFG) and oxygenated gasoline provisions were added. The RFG provision requires use of RFG all year in certain areas. The oxygenated gasoline provision requires the use of oxygenated gasoline during certain months, when CO and ozone pollution are most serious. The regulations also require certain fleet operators to use clean-fuel vehicles in 22 cities.
Clean Air Act Amendments of 1990
This legislation to improve the quality of the atmosphere and curb acid rain promotes the use of cleaner fuels in vehicles and stationary sources.
Clean Development Mechanism
(CDM) A Kyoto Protocol program that enables industrialized countries to finance emissions-avoiding projects in developing countries and receive credit for reductions achieved against their own emissions limitation targets.
Clean diesel fuel
An evolving definition of diesel fuel with lower emission specifications, which strictly limit sulfur content.
Cleaner
A product to purify or remove unwanted substances.

Also See
Abrasive cleaner
Air cleaner
Air cleaner horn
Air filter
Brake System Cleaner
Carburetor Cleaner
Low-profile air cleaner
Oil bath air cleaner
Paper air cleaner
Piston ring groove cleaner
Thermostatic air cleaner


Cleaner Bi-metal Sensor

See
Air Cleaner Bi-metal Sensor

Cleaner Duct And Valve Vacuum Motor

See
Air Cleaner Duct And Valve Vacuum Motor

Cleaner element

See
Air cleaner element

Cleaner horn

See
Air cleaner horn

Cleaner intake

See
Air Cleaner Intake

Clean Fuel
The CAA (as amended in 1990) specification that identifies RFG and alternative fuels as clean fuel.
Clean-Fuel Fleet Program
Federal program requiring fleet purchase of Clean-Fuel Vehicles beginning in 1988.
Clean-Fuel Vehicle
(CFV)A vehicle that has been certified by the EPA to meet the clean-fuel standards of the Clean Air Act Amendments of 1990. The three categories of federal CFV standards from least to most stringent are LEV, ULEV, and ZEV. The ILEV standard is voluntary and does not need to be adopted by states as part of the Clean-Fuel Fleet Program. CFVs are eligible for two federal programs, the California Pilot Program and the Clean-Fuel Fleet Program. CFV exhaust emissions standards for light-duty vehicles and light-duty trucks are numerically similar to those of CARB's California Low-Emission Vehicle Program.
Cleaning

See
Abrasive Blast Cleaning
Blast cleaning
Self-cleaning

Cleaning unit

See
Spray gun nozzle cleaning unit

Clean oil
Fresh oil that has not been used in a vehicle before.
Clean oil lubrication
A lubrication system where fresh oil is supplied to the engine as needed -- such as in a two-stroke engine.
Clean shot
Trucker slang for "No highway patrol around" as in "Large Car you got a clean shot all the way to the state line."
Clearance
A given amount of space between two parts such as between Piston and Cylinder, bearing and Journal , etc.

Also See
Bearing clearance
Crest clearance
Front wheel tire clearance
Ground clearance
Ground clearance control
Lateral clearance
Lateral tire clearance
Longitudinal tire clearance
Pedal clearance
Piston clearance
Piston ring side clearance
Valve clearance
Vertical tire clearance

Clearance control

See
Ground clearance control

Clearance depression

See
Valve clearance depression

Clearance fit
Parts that are assembled so that there is clearance between them so that one part can slide in or on the other. Also called sliding fit
Clearance height
  1. The distance between the ground and the lowest portion of the bottom of a vehicle (not counting the wheels). Also called ground clearance.
  2. The distance between the top of a vehicle and the bottom of a bridge or tunnel which determines whether the vehicle can pass under it.
Clearance lamp
A light which is mounted on the extreme edges of the roof of a truck to show the maximum height and width of a vehicle. Also called marker lamp.
Clearance pocket compressor
Small space in a cylinder from which compressed gas is not completely expelled. This space is called the compressor clearance space or pocket. For effective operation, compressors are designed to have as small a clearance space as possible.
Clearance sensor

See
Ground clearance sensor

Clearance volume
The space above a piston when it is at the top dead center.
Clear coat
A clear paint covering used on modern vehicle bodies. It is the top coat.
Clear flood mode
A situation in which a carburetor or fuel injection system increases the amount of air or reduces the amount of fuel when necessary to correct a problem of Flooding.
Clear lacquer
A paint finish or sealer that is "crystal-clear" transparent, durable, dries rapidly, and usually does not require sanding.
Clear system

See
Base and clear system

Clearwater stern
A stern with a shoeless stern frame
Cleat
  1. An attaching bracket
  2. Clips at intervals on the horizontal stiffeners of hatch coamings to secure the hatch covers
  3. A fitting with two prongs which is attached to the wall of a cargo ship or trailer so that one end of a rope or strap could be knotted and the other end secures the shipment or the shipping mats or battens in place. Also called a kevel.

Also see
Pedal Cleats

CLEPA
Acronym for Comité de Liaison de la Construction d'Equipements et de Pièces d'Automobiles (i.e., European Association of Automotive Suppliers).
Clevis
A U-shaped metal piece with holes in each end through which a pin or bolt is run, used for attaching the brake pedal to the power brake booster pushrod, the clutch pedal to the clutch cable or master cylinder pushrod and for various other connections on an automobile. Clevises are sometimes used in other parts of the brake system, like attaching the parking brake cable to the parking brake lever at the rear brakes
Clevis pin
clevis pin

Clevis pin

A cylinder with a head at one end and a hole at the other. When the clevis pin is inserted into a hole, the head prevents it from going all the way through. A Cotter pin or Hitch pin clip is inserted in the other end of the clevis pin to keep it secure.
Click
  1. The action of inserting a bicycle shoe's bracket into the receiving part of a click-in pedal (formerly known as a clipless pedal).
  2. A colloquial term for a Kilometer
Click-in pedals
clipless pedal

Click-in Pedal

A term for road bike pedals that use a releasable mechanism like that of a ski binding to lock onto cleated shoes and do not use toe clips or straps. Replaces the term Clipless pedals. Some brands are SPD, Look, Time, and Speedplay.
Click-type torque wrench
A torque wrench which gives out an audible click when the preset torque is reached.
Climate change
  1. The international concern that increasing concentrations of greenhouse gases (GHGs) in the atmosphere are changing the climate in ways detrimental to our social and economic well-being.
  2. A term used to refer to all forms of climatic inconsistency, but especially to significant change from one prevailing climatic condition to another. In some cases, climate change has been used synonymously with the term global warming; scientists, however, tend to use the term in a wider sense inclusive of natural changes in climate, including climatic cooling.
Climate control
  1. A lever or button which you can move to change the temperature in the passenger compartment of a vehicle. It controls the heater, vent, and/or air conditioner.
  2. A space in which an ideal climate is maintained by some devices.

Also see
Electronic Climate Control

Climatic chamber
A test area into which an automobile can be placed to see if it will meet the extremes of temperature and humidity.
Climber
A vehicle salesman who can sell anything to anyone--even the tough customer.
Climbing ability
While some vehicles may have a high top end speed on a road with no incline, the real test of a vehicle in mountainous terrain is its ability to go up a hill at an adequate speed (i.e., its climbing ability).
Clincher
A tire whose edges hook under the curved-in hooked edge of a special rim, not commonly found anymore on Bicycles and often confused with the common Wired-on tire.
Clincher rims
Type of wheel rim used with early beaded-edge tires
Clincher tire
A tire whose edges hook under the curved-in hooked edge of a special rim, not commonly found anymore on Bicycles and often confused with the common Wired-on tire.
Clinch nut
A nut having a pilot which, after insertion in a hole, is clinched or staked in place to prevent rotation.
Clinker
Powdered cement, produced by heating a properly proportioned mixture of finely ground raw materials (calcium carbonate, silica, alumina, and iron oxide) in a kiln to a temperature of about 1480°C.
Clinometer
An instrument which measures the steepness of a hill.
Clip
  1. To move at a fast pace
  2. The removable front end of a vehicle, usually one designed for racing.
  3. A securing fastener

Also See
Alligator clip
Angle Clip
Bonding Clip
Crocodile clip
Cushion Clip
Hitch Pin Clip
Horseshoe Clip
Hose clip
Hose clip installer
Hose clip pliers
Jubilee clip
Pedal Toe Clip
Rebound clip
Seat Cover Clip
Spring clip

Clip installer

See
Hose clip installer

Clipless pedal

See
Clipless pedals.

Clipless pedals
click-in pedal

Clipless pedal

An obsolete term for road bike pedals that use a releasable mechanism like that of a ski binding to lock onto cleated shoes and do not use toe clips or straps. Preferred term is Click-in pedals. Some brands are SPD, Look, Time, and Speedplay.
Clip-on engine
An engine that is attached to a conventional bicycle frame
Clip-ons
  1. Low racing handlebars for a motorcycle that clamp directly onto the fork legs
  2. Handlebars that attach directly to the fork tubes, rather than to the top yoke, that hold the fork tubes together
Clip-on weight
A wheel weight that is clipped on the rim between the rim and the tire. It is used to balance a wheel.
Clip Pedals

See
Toe Clip Pedals

Clip pliers

See
Hose clip pliers

Clip screw
A fastener that is secured in place by a screw.
Clip screw gate
Clip screw gate

Clip screw gate

A D-shape carabineer
CLNT
Acronym for Coolant
Clock
  1. An instrument showing the time.
  2. An odometer as in the statement I want to buy this car, but it has too many miles on the clock.
  3. To record the speed or time that vehicle makes.
  4. To turn the odometer back (an illegal practice)

Also see
Analog Clock
Cesium Clock

Clocking
  1. The action of recording the speed of a vehicle.
  2. In Britain, it is the action of turning the odometer back.
C/locking
Abbreviation for central locking.
Clockwise
Rotation to the right like the direction of clock hands. In most cases it is the direction to secure a nut to a bolt. It is the opposite to Counterclockwise.
Clog
To obstruct a passageway or track so that the normal flow or operation of something is hindered.
Close call
In driving it is the near possibility of an accident.
Close coils
The coils or loops of a spring which are tightly together.
Close coupled sedan

See
Close-coupled sedan.

Close-coupled sedan
Similar to the Sedan, this body style is shorter and thus usually accommodates only five passengers. The rear quarter windows were eliminated.
Closed car
A vehicle with a hard top (i.e., not a convertible)
Closed circuit
Electrical circuit in which electrons are flowing.
Closed container
Container sealed by means of a lid or other device so that neither liquid nor vapor will escape from it at ordinary temperatures.
Closed cooling system

See
Coolant recovery system.

Closed crankcase ventilation
A system in which Crankcase vapors are discharged into the engine Intake system (usually through the Intake manifold) and pass through the engine Cylinders rather than being discharged into the atmosphere.
Closed Distribution System
A shipping system confined to moving goods between specified plants and facilities.
Closed-end connector
Solderless connector shaped like a hat. Used to join two, three, or more wires together. Similar to wire connectors used in home wiring, but installed by crimping instead of twisting
Closed end lease
Most leases offered today are close-end leases, meaning that the residual value is fixed and stated in the lease contract. The lessee's financial obligations are unaffected by what the vehicle is actually worth when the lease ends. In other words, the lessee assumes no risk for the depreciation of the vehicle.
Closed loop
  1. An operating condition or mode which enables modification of programmed instructions based on a feedback system
  2. A condition, after the appropriate sensors have indicated that predetermined conditions have been met, where the computer actively controls the fuel system and other functions based on exhaust gas conditions and other parameters.
  3. The repeated times when the EFI computer uses the feedback on the mixture provided by the oxygen sensor to control the injected amounts of fuel.
Closed-Loop Carburetion
System in which the fuel/air ratio in the engine is carefully controlled to optimize emissions performance. A closed-loop system uses a fuel metering correction signal to optimize fuel metering.
Closed loop fuel control
The normal operating mode for a feedback carburetor system. Once the engine is warmed up, the computer can interpret an analog voltage signal from an exhaust gas oxygen sensor and alter the air/fuel ratio accordingly with a duty-cycle solenoid or solenoid-controlled valve.
Closed loop mode
Once the engine has reached warm-up temperature, the engine management computer collects the precise data from all the sensors (coolant temperature sensor, throttle position sensor, oxygen sensor, etc.) to determine the most efficient air/fuel mixture for combustion.
Closed loop system
  1. A self-adjusting system which keeps conditions stable and is controlled by negative Feedback from a sensor.
  2. A computer controlled system which monitors the exhaust gas with a sensor and adjusts the fuel delivery, and may or may not adjust spark timing, transmission, and other devices to meet emission and driveability criteria
Closed system
An anti-lock brake system with some means, generally a pump, to restore hydraulic pressure that's bled off during an ABS stop
Closed type check valve
A valve which allows fluid flow in only one direction.

Also See
Check valve
Open type check valve
Residual pressure valve
Residual brake pressure type check valve
Two-way type check valve

Closer
Usually a pushy salesman who is assigned to convince a hesitating customer to make the purchase of a vehicle when the original salesman can't make the sale.
Close-ratio gearbox
A transmission in which there is very little difference between one gear ratio and the next. This kind of transmission makes it easy for fast shifting.
Closes

See
Exhaust valve closes
Intake valve closes

Closing

See
Automatic closing system

Closing cam
A cam or rocker which closes a valve in a mechanically operated valve system. Other types close the valve through the operation of the valve spring. Also called closing rocker.
Closing force
The force needed for the spring to close a valve.
Closing panel
A panel which covers a hole in the body, interior panels, or frame.
Closing rocker
A cam or rocker which closes a valve in a mechanically operated valve system. Other types close the valve through the operation of the valve spring. Also called closing cam.
Closing system

See
Automatic closing system

Closure

See
Road closure

Cloth

See
Beaver Cloth
Emery cloth
Tack cloth

Cloth upholstery
The fabric of the seats made of cloth rather than leather or vinyl.
Cloud point
(CP)
  1. The temperature at which Diesel oil tends to thicken and cloud up (i.e., become cloudy).
  2. A measure of the ability of a diesel fuel to operate under cold weather conditions. Defined as the temperature at which wax first becomes visible when diesel fuel is cooled under standardized test conditions.
Cloverleaf
A highway overpass system which has four basic loops for getting on the highway or leaving it.
Club
club

Club

A security device which surrounds the steering wheel making it difficult for a thief to operate the steering wheel.

Also See
Royal Automobile Club


Club Cab
clubcab

Club Cab

A type of pickup truck (by Dodge) which has a second row of seating; but unlike a crew cab (which has four full size doors) it has a half-door that can be opened only after the main door is opened. The seating is usually a little more cramped than in a crew cab. Also called Extended Cab, King Cab, XtraCab, Access Cab, SuperCab, or Cab Plus.
Club coupe
club coupe

Club Coupe

The club coupe designation seems to come from club car, describing the lounge (or parlor car) in a railroad train. The early postwar club coupe combined a shorter-than-sedan body structure with the convenience of a full back seat, unlike the single-seat business coupe. That name has been used less frequently in the 1976-86 period, as most notchback two-door models (with trunk rather than hatch) have been referred to as just coupes. Moreover, the distinction between two-door coupes and two-door sedans has grown fuzzy.
Club hammer
A hammer with a short handle but a large, heavy head. It is used to hit the back end of a chisel or drift.
Club Parisien

See
Audax Club Parisien

Clunker
A vehicle which might run but is rusty and in need of a lot of repair work.
Cluster

See
Analog cluster
Electronic cluster
Footpedal cluster
Instrument cluster
Lamp cluster
Rear lamp cluster
Seat cluster

Cluster gear
The cluster of gears that are all cut on one long gear blank. The cluster gears ride in the bottom of the Transmission. The cluster provides a connection between the transmission Input shaft and the Output shaft. Also called Counter gear.
Cluster head
A set of traffic lights mounted on a backplate.
Cluster panel
The reverse side of the Instrument panel or Dash where all the wiring or circuit board is located.
Clutch
Coil spring clutch

Click image to supersize
Coil spring clutch

  1. An electrically operated coupling device that connects or disconnects the compressor pulley and compressor shaft
  2. A device that disconnects the engine from the Transmission, to allow the vehicle to change gears, and then allows the engine and transmission to resume contact and turn together at a new Speed.

Also See
Band Clutch
Block Clutch
Center the clutch
Centrifugal clutch
Clutch diaphragm spring
Clutch disc
Clutch explosion
Clutch housing
Clutch lever
Clutch pedal free travel
Clutch pedal
Clutch pilot bearing
Clutch pressure plate
Clutch semi-centrifugal release fingers
Clutch shaft
Clutch solenoid
Clutch throwout fork
Coil spring clutch
Cone clutch
Diaphragm spring clutch
Diaphragm clutch
Disengage the clutch
Dog clutch
Double clutching
Dry clutch
Electromagnetic clutch
Fan clutch
Fluid clutch
Freewheeling
Friction clutch
Heavy clutch
Hydraulically-activated clutch
Hydraulically-assisted clutch
Light clutch
Lock-up clutch
Magnetic clutch
Multi-plate clutch
Multiple-plate clutch
Multiple disc clutch
One way clutch
Overrunning clutch starter drive
Overrunning clutch
Pull-type clutch
Push-type clutch
Reverse clutch
Riding the clutch
Roller clutch
Single-plate clutch
Slip the clutch
Sprag clutch
Stator roller clutch
Torque converter lock-up clutch
Twin-plate clutch
Wet clutch


Clutch aligning set
A group of tools used to align the clutch plates with the flywheel. Usually there is a shaft, pilot bearing adapters, and tapered universal sleeves
Clutch aligning tool
A tool which looks like a bar or a disc which can be used to line up the clutch plates with the flywheel.
Clutch antirattle spring clip
Antirattle spring

Antirattle spring

A specially shaped wire that prevents the clutch plate and spring from making noise when no pressure is applied to the plate.
Clutch brake
A device for slowing down the clutch discs (and thus the gears themselves) so that shifting is smoother and quieter.
Clutch cable
A cable (usually a cluster of thin strands within a plastic sheath) which operates the movement of the clutch plates. At the other end is a pedal (in automobiles) or a handlebar lever (left side).
Clutch compressor signal

See
Air Conditioner Clutch Compressor Signal

Clutch cover
A metal cover which encases the clutch plates.
Clutch cycling switch
A device that turns the compressor on and off in response to changes in pressure or evaporator temp
Clutch diaphragm spring
Clutch diaphragm spring

Clutch diaphragm spring

A round dish-shaped piece of Flat spring steel. It is used to force the Pressure plate against the Clutch disc in some Clutches.
Clutch disc
Clutch disc

Clutch disc

A spinning plate located at the end of the Driveshaft facing the engine Flywheel and covered with a Friction material such as Asbestos. When the Clutch is engaged, the disc is squeezed between the Flywheel and the Clutch pressure plate, causing the engine and the Transmission to turn at the same Speed. British term is called clutch plate.
Clutch disk

See
Clutch disc

Clutch drag
When the clutch discs do not disengage completely after the clutch pedal is depressed or the clutch lever is pulled in, there is excessive friction so that it is difficult to shift gears because both the driven discs and the input shaft are both rotating.
Clutch explosion
Clutches have literally flown apart (exploded) when subjected to high rpm, a Scatter shield is used on competition cars to protect the Driver and spectators from flying parts in the event the Clutch explodes.
Clutch facing
The asbestos-type lining on a clutch plate.
Clutch field
A clutch part on an air condition compressor, consisting of hundreds of windings of wire, that creates a magnetic field when current is applied, pulling in the armature to engage the clutch
Clutch fork
When the clutch pedal (or lever) is depressed, it pulls on a cable which moves the clutch fork which in turn pushes on the release bearing and disengages the clutch discs. Also called Clutch release fork.
Clutch housing
A Cast iron or Aluminum Housing that surrounds the Flywheel and Clutch mechanism. Also called Bell housing.
Clutching
The act of operating the clutch in order to shift gears

Also see
Double clutching

Clutch interlock switch
A switch that prevents the vehicle from starting unless the clutch pedal/lever is pressed.
Clutch judder
A British term for clutch shudder.
Clutch lever
A hand-operated blade located on the left side of the Handlebar of a Motorcycle. When the clutch lever is pulled in, it disengages the clutch so the engine and the Crankshaft can turn independently of the Transmission and the rider can change gears.

Also See
Clutch release finger


Clutch lining
The friction material on the face of the clutch discs.
Clutch, magnetic
Clutch built into automobile compressor flywheel. operated magnetically. which allows pulley to revolve without driving compressor when refrigerating effect is not required.
Clutch orifice tube system

See
Cycling Clutch Orifice Tube System

Clutch pedal
A foot-operated pedal located on the floor of the vehicle to the left of the Brake pedal on cars with Manual transmission. When the clutch pedal is depressed, it disengages the clutch so the engine and the Crankshaft can turn independently of the Transmission and the Driver can change gears.
Clutch pedal free travel
The specified distance that the Clutch pedal may be depressed before the throwout bearing actually contacts the clutch release fingers.
Clutch pilot bearing
A small Bronze Bushing, or in some cases a Ball bearing, placed in the end of the Crankshaft or in the center of the Flywheel depending on the vehicle, that is used to support the outboard end of the Transmission Input shaft.
Clutch plate
The clutch discs.
Clutch pressure plate
Clutch Pressure Plate

Clutch Pressure Plate

That part of a Clutch assembly that through spring pressure, squeezes the Clutch disc against the Flywheel thereby transmitting a driving force through the assembly. To disengage the Clutch, the pressure plate is drawn away from the Flywheel via Linkage.
Clutch pulley
The clutch part turned by the drivebelt. The pulley or rotor free-wheels until the clutch is engaged. On rotors which contain the field, the electrical connection is made through brushes similar to alternator and starter motor brushes
Clutch release bearing

See
Throwout bearing.

Clutch release finger
A flat piece of metal shaped like a curved finger. Through the movement of the throwout fork, the throwout bearing pushes against the clutch release fingers or levers to release pressure against the Pressure plate. Also called clutch release lever.
Clutch release fork
Clutch Release Fork

Clutch Release Fork

A lever attached to the clutch throw-out bearing. When the fork presses the throw-out bearing against the center of the conical diaphragm spring, it pops inward, releasing the pressure plate from the flywheel and freeing the clutch disc so that the engine can turn without driving the transmission.
Clutch release lever

See
Clutch release finger.

Clutch rotor
The clutch part turned by the drivebelt. The pulley or rotor free-wheels until the clutch is engaged. On rotors which contain the field, the electrical connection is made through brushes similar to alternator and starter motor brushes
Clutch semi-centrifugal release finger

See
Clutch semi-centrifugal release fingers.

Clutch semi-centrifugal release fingers
Clutch release fingers that have a weight attached to them so that at high rpm the release fingers place additional pressure on the Clutch pressure plate.
Clutch shaft
The shaft that takes power from the clutch into the Gearbox. Also called the Drive pinion.
Clutch shudder
When the clutch tries to engage (when the pedal or lever is released), but the discs do not mate securely, the discs engage intermittently and slip past each other making a noise like a shudder. In Britain, it is called clutch judder.
Clutch slip
Clutch slip occurs when the clutch tries to engage (when the pedal or lever is released), but the discs do not mate securely.
Clutch solenoid
In some automotive Air conditioners, a Solenoid that operates a clutch on the Compressor drive Pulley. When the Clutch is engaged, the Compressor is driven and cooling takes place.
Clutch spring
The clutch cover will have several posts over which the clutch spring (shaped like a cylinder) fits and pushes the pressure discs against the driven clutch discs to transmit power.
Clutch starter

See
Overrunning clutch starter drive

Clutch starter drive

See
Overrunning clutch starter drive

Clutch starter interlock
A device which disengages the starter once the engine has started.
Clutch stop
A clutch brake
Clutch throw-out bearing
Throw-out bearing

Throw-out bearing

A part of the Clutch activated by the Clutch pedal that allows the Clutch to disengage. If you allow the vehicle to Idle in gear with the Clutch pedal depressed, instead of shifting to Neutral gear, you can wear out the throwout bearing. The British term is Clutch release bearing.

Also See
Free pedal play
Clutch throw-out bearing


Clutch throwout fork
The device or fork that straddles the throwout bearing and that is used to force the throwout bearing against the clutch release fingers.
Clutch thrust bearing
The clutch release bearing.
Cluttered engine compartment
An engine compartment or bay in which all the available space around the engine is occupied by other objects (alternator, pumps, air intake system, battery, wiper motor, heater motor, windshield washer motor, starter, radiator, air conditioner, hoses, pipes, wiring, electronic boxes, etc.)
CLV
Acronym for Calculated Load Value