Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Fl"

Flag: See
Black and white checkered flag
Black flag
Checkered flag
Green flag
Green flag with yellow diagonal stripe
National flag
Red flag
White flag
Yellow flag

Flag down: The action of a pedestrian to stop a vehicle by using a hand signals (usually waving the arms laterally above the head). This is usually a sign of an emergency

Flagship model: The prestige model or top model of a manufacturer's line of vehicles, e.g., "Cadillac is the flagship model for GM and Lincoln is the flagship model for Ford."

Flags of convenience: Flags of nations which offer favorable tax structures and regulations. Ships registering under the laws of these nations are not always required to establish their home location in that country.

Flake: The action of paint when it starts to come off the surface in small, thin sections

Flake off: The action of paint when it starts to come off the surface in small, thin sections

Flaking: The tendency of paint to lift away from the surface because of poor adhesion.

Flame: See
Cutting flame
Neutral flame
Oxidizing flame
Oxygen-hydrogen flame
Oxygen-lp gas flame
Reducing flame
Sheath flame

Flame cutting: Cutting performed by an oxygen-fuel gas torch flame which has an oxygen jet.

Flame front: The term used to describe certain aspects of the fuel Explosion in the Cylinders. The flame front should move in a controlled pattern across the Cylinder, rather than simply exploding immediately.
Also See
Pinging

Flame glow plug: A glow plug that preheats the intake air by burning a small quantity of precisely metered fuel

Flame paint: 1933 Ford with flame paint

A popular (during the 1950s) special paint design applied to the front of custom cars. Large flames in yellow, orange, and red were painted on the side of the car from the back of the front wheels toward the back

Flame path: The distance from the spark plug to the farthest part of the combustion chamber

Flame test for leaks: Tool which is principally a torch. When a halogen mixture is fed to the flame, this flame will change color in the presence of heated copper.

Flame trap: A device consisting of a valve or similar, preventing the escape of ignited Blow back gases, usually located in the hose or pipe leading from the Crankcase to the intake tract

Flammable Liquid

Flammable liquids are Class I liquids. A liquid having a flash point below 37.8°C and having a vapor pressure not exceeding 276 k_Pal at 37.8°C. Class I liquids are subdivided as follows:

Class IA -- Includes those having flash points below 22.8° and having a boiling point below 37.8°C.
Class IB -- Includes those having flash points below 22.8° and having a boiling point at or above 37.8°C.
Class IC -- Includes those having flash points at or above 22.8° and below 37.8°C.

Combustible liquids

Flange

A projecting rim or collar on an object for keeping it in place.
The parts of a Hub shell to which Spokes are attached and which secure the tire on the rim base.
The circle of metal inside the teeth on a Chainring.
Right angle bends in sheet metal designed to give rigidity or to eliminate a sharp edge. Commonly called bends.

Also See
B-flange
Body flange
Demountable flange
Heater flange
J-flange
K-flange
Rim flange
Spot-welded flange
Windshield mounting flange

Flange bolt: A bolt with a Fillet as part of the bolt head

Flanged: Something that has a flange

Flanged head: A bolt head which has a Fillet (i.e., it looks as though it already has a washer under the head; but the washer is part of the head)

Flange height: A measurement from the top of the flange to the Bead seat, and is the difference between the overall diameter and Nominal rim diameter, divided by two.

Flange joint: A coupling between two shafts formed of two disc-shaped flanges on the ends of the shafts which are bolted to each other

Flanger: A tool for making a flange.

Also See
Panel flanger

Flange seal: An L-shaped rubber seal used in some earthmover tubeless tire mountings. It prevents air loss between the tire beads and both the flange and rim base, and the flange and loose taper seat.

Flange-type puller: A puller with legs that fit behind a flange on a hub

Flanging: The action of putting on a flange

Flanging tool: Flanging tool

A tool (like pliers) for making a flange by bending the metal

Flank

The side of a screw thread, rising from the bottom of the groove to the top of the ridge
One of the two flat parts of the face of a cam

Flap

A rubber protector used in tube-type truck tires to prevent injury to the tube by the bead toes and at the valve slot of the rim.
A flat piece of material attached along one side, often by a hinge and forming a small door for shutting off an opening.

Also See
Anti-spray flap
Fuel filler flap
Mud flap
Sensor flap
Ski flap

Flappers: Trucker slang for ears as in "Anybody got their flappers on out there?"

Flapper valve: Thin metal valve used in refrigeration Compressors which allows gaseous Refrigerants to flow in only one direction.

Flare

A flange or a cone-shaped end applied to a piece of tubing to provide a means of sealing two similarly angled areas formed in fitting the body and the nut.
A sudden burst of flame.
The spreading out of the hull form from the central vertical plans, usually in the front, much like the end of a trumpet.
A gradual spreading or widening of a tube.
An enlargement at the end of a piece of flexible tubing by which the tubing is connected to a fitting or another piece of tubing. This enlargement is made at about a 45 deg. angle. Fittings grip it firmly to make the joint leakproof and strong.

Also See
Double flare

Flared: Gas disposed of by burning in flares usually at the production sites or at gas processing plants.

Flared wheel arch: A wheel arch bent outwards around its circumference, usually to accommodate wider wheels and/or tires

Flare nut: A nut fitting over the flared end of a brake or fuel pipe at a union and used to clamp the tubing flare against another fitting.

Flare nut spanner: British term for Flare nut wrench

Flare nut wrench: Flare nut wrench

A wrench which looks almost like an open end wrench except the end curls around the nut further. The opening allows the wrench to slide over a tube or pipe to which a nut is attached, but not directly over the nut. Thus you have to slide it over the pipe first and then bring it up to the nut. The wrench has more faces than an open end wrench thus giving better gripping.

Flareside Truck: Flareside Truck

Ford's term for a pickup truck style in which there is some kind of indentation just behind the cab to allow you to enter the bed in contrast to a Styleside truck. Chevrolet calls this style Stepside

Flaring tool: Flaring tool

A tool used to form Flare connections on tubing.

Flash

The first stage of the drying process of paint where most of the Solvents evaporates.
A sudden burst of energy.
When crude oil is heated the lighter or more volatile vapor is separated and travels to the top of the tank. This travelling is called flash.
The impact of electric arc rays against the human eye.
The fin of surplus metal formed at the seam of a resistance weld.
To use your signal lights as in "My car was flashing left."
To rapidly switch the Headlights off and on -- usually to indicate a warning. If you are behind someone and you flash your headlights, it means that you want him to pull over so you can pass. If you see someone flashing his lights, it could mean that there is a police car ahead so slow down; or it could mean there is danger ahead (e.g., deer on the road, an accident ahead, etc.).

Flashback: Another term for Blow back

Flasher

A flashing signal light.
An electronic switch apparatus controlling the operation of the signal lights, including their rate of flash; self-cancelling when the steering wheel is returned to the straight-ahead position.
An electronic relay which regulates the signal lights and emits a clicking or chiming sound.

Also See
Hatchback hazard flasher switch
Headlight flasher
Side flasher

Flasher switch: See
Hatchback hazard flasher switch
Hazard flasher switch

Flash gas: Instantaneous evaporation of some liquid Refrigerant in evaporator which cools remaining liquid refrigerant to desired evaporation temperature.

Flashover: Tendency of electrical Current to travel down the outside of a Spark plug instead of through the center Electrode. It usually occurs when the sparkplug is dirty or oily since electricity finds that to be the path of least resistance.

Flash point

The point in the temperature range at which a given oil (especially Diesel oil) in vapor form will ignite and flash into flame. The higher the flash point, the better the lubricating quality of the oil. The temperature at which the vapor continues to burn is called the Fire point".
Temperature at which flammable liquid will give off sufficient vapor to support a flash flame but will not support continuous combustion.
The minimum temperature at which the liquid gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid within the vessel as specified by appropriate test procedure and apparatus as follows:
1. The flash point of a liquid having a viscosity less than 45 SUS at 37.8°C and a flash point below 93.4°C is determined in accordance with the Standard Method of Test for Flash Point.
2. The flash point of a liquid having a viscosity of 45 SUS or more at 37.8°C or a flash point of 93.4°C or higher is to be determined in accordance with the Standard Method of Test for Flash Point.

Flashpoint apparatus: See
Abel flashpoint apparatus.

Flash time: The time required for a Coat of paint to lose most of its Solvent through Evaporation.

Flash weld: Resistance type weld in which mating parts are brought together under considerable pressure while a heavy electrical current is passed through the joint to be welded.

Flat

When a battery has completely discharged, so that it cannot turn over the engine then the battery is said to be flat.
To be completely deflated, especially as the result of a puncture or a leaky valve.

Also See
Flat tire.
A flat tire.
To experience a flat tire as in "While riding my bike, I flatted."
An engine having horizontally opposed cylinders.
A level area on an otherwise rounded surface.
To give a final light rubbing down to (paintwork or filler) with fine grade sandpaper or similar, to prepare the surface for a top coat.

Also See
Battery is flat
Go flat
Keel, flat plate
Outboard flat hump
Outboard flat pente
Run flat
Across flats

Flat base rim: A truck rim with no center depression. A demountable flange (consisting of 1 or 2 piece side/lock ring) permits the removal of the tire and holds it in place after installation.

Also See
Flat base rim taper

Flat base rim taper: An obsolete form of rim with no taper at either Bead seat.

Flat battery: A British term for a Dead battery

Flatbed trailer: Flatbed trailer

A trailer with a flat deck (and no sides or top) so that any size or shape item can be loaded (within reason) regardless of height, length, or width

Flatbed truck: Flatbed truck

A truck with a flat deck (and no sides or top) so that any size or shape item can be loaded (within reason) regardless of height, length, or width

Flat-bladed screwdriver: A screwdriver which has a blade at its end to fit slotted screws. This type is the least desirable screw giving the least amount of torquing ability. If the screwdriver does not fit well, the screw is easily damaged.

Flat crank: A Crankshaft having one of the bearing Journals out-of-round.

Flat cylinders: Found in the flat-four- and flat-six-cylinder engines used in Honda's Gold Wings, the cylinders are arranged in a flat, opposing configuration

Flat eight: An eight cylinder engine with four cylinders on each side. The "left" bank of four cylinders is directly opposite the right bank.

Flat engine: Flat engine

An engine where opposite Cylinders are 180 degrees apart. This engine type is found on the VW Beetle, Corvair, Porsche six-cylinder, Subaru quadrazontal, and BMW Motorcycle engines.

Flat file: A long, thin rectangular bar (like a blade) with angled grooves cut into the top and bottom of the larger sides and used to shape metal

Flat four: Flat four

A four cylinder engine with two cylinders on each side. The left bank of two cylinders is directly opposite the right bank.

Flathead: Flathead

An engine with all the valves in the block on one side of the Cylinder. Also called L-head because the cylinder acts as one side of an inverted L while the valves act as the other side. Since there are no valve in the head, the head can be flat.

Flat hump: A raised and flattened portion on the Bead seat of some wheel rims which retains the beads of an insufficiently inflated tire on the bead seat, thereby preventing the tire beads from jumping into the rim well.

Also See
Outboard flat hump

Flat key: A small bar of any length but its width is greater than its height.

Flat-nose pliers: A common pair of pliers where the ends of the jaws do not extend to a point (like Long-nose pliers); but are cut short. Also called flat-nosed pliers.

Flat-nosed pliers: Flat-nosed pliers

A common pair of pliers where the ends of the jaws do not extend to a point (like Long-nose pliers); but are cut short. Also called flat-nose pliers.

Flat pente: A raised portion on the Bead seat of some wheel rims which retains the tire beads of an insufficiently inflated tire on the bead seat, thereby preventing the beads from jumping into the rim well. This is a compromise between the Contre pente and the Flat hump contours and is mainly used on passenger cars made in France.

Also See
Outboard flat pente

Flat plate: See
Keel, flat plate

Flat plate cells: Fuel cells that are structurally planar.

Flat plate keel: The horizontal, centerline, bottom shell strake constituting the lower flange of the keel

Flat plate pumped: A medium-temperature solar thermal collector that typically consists of a metal frame, glazing, absorbers (usually metal), and insulation and that uses a pumped liquid as the heat-transfer medium: predominant use is in water-heating applications.

Flat position: A horizontal weld on the upper side of a horizontal surface.

Flat position welding: Creating a horizontal weld on the upper side of a horizontal surface. Also called downhand welding

Flat rate: A pre-determined length of time set down by the manufacturer that a particular repair job will take and is listed in the Flat rate manual. If the flat rate is two hours, but the mechanic completes the job in more or less time, you will be charged for two hours. For the shop, flat rate encourages mechanics to work harder to beat the prescribed time, thus earning more for the shop and the mechanic; but it also hurts the shop when the mechanic cannot complete the job because of other contributing factors (i.e., a bolt which should have taken 10 seconds to remove breaks off and requires 30 minutes to remove). For the customer, flat rate means fair pricing for the same job no matter how long it actually took. Thus both Sam's labor bill and my labor bill to do the same work is the same cost. It can be unfair if the mechanic worked faster on my vehicle (because I keep it in excellent shape) than on Sam's vehicle (because his involved a lot more cleaning, etc. to do the job). Also, there is the danger that a mechanic may take shortcuts in order to beat the flat rate, but which may cause mechanical problems later. Charging by the actual time the mechanic takes is called Straight time.

Flat rate manual: A listing of almost every job that can be done on a vehicle with the time required for a mechanic to do the work. It is used in service shops to determine labor charges. If a mechanic completes the job before the Flat rate time, the Customer is still charged the flat rate time. If he exceeds the flat rate time, the Customer is not charged for Straight time, but the lower flat rate time.

Flat seat: The seat of a spark plug which is sealed by means of a gasket

Flat six: A six cylinder engine with three cylinders on each side. The left bank of three cylinders is directly opposite the right bank.

Flat spot

Refers to a spot during an Acceleration period where the engine seems to lose power for a moment and will then begin to pull again.
Irregular wear in an isolated spot or spots around the tire tread. It is usually caused by locking the brakes so that the tire skids on the ground.

Flat spring: A long bar that is bent in the middle. When pressure is applied to the outside ends, the middle flexes.

Flat tank: Fuel tank shape used on early motorcycles

Flat tappet: A tappet with a flat contact surface towards the cam lobe

Flat tire: A condition where an air-inflated tire is no longer pressured up with air. The problem may be a cut in the casing or tube; or may be caused by a bad valve. When you experience a flat tire, no doubt some wit will tell you that your tire is flat only on the bottom.

Flat-tip screwdriver: See
Flat-bladed screwdriver

Flat-topped piston: A piston with a flat not domed crown

Flat-top piston: A piston with a flat not domed crown

Flat twin: A two cylinder engine with one cylinder on each side. The left cylinder is directly opposite the right cylinder.

Also See
Horizontally opposed

Flat washer: A disc like a coin with a hole in the middle

Flaw: A defect usually in the surface of the paint

FLC: Acronym for Fluid Lock-up Converter (Ford)

FLE: Acronym for Full Load Enrichment

Flèche vélocio: A 24-hour team Bicycle ride covering at least 360 kilometers held over the Easter weekend in France.

Fleet: All the vehicles owned by a company or other organization

Fleet car: A company will purchase a number of cars at a low price, often basic models, from one manufacturer. When the company decides to sell these cars, it will advertise that they were fleet car. Fleet cars have the advantage of regular maintenance; but the disadvantage of high mileage.

Fleet sales: The purchase of vehicles by a business that meet a minimum requirement of units sold.

Fleetside: Fleetside

Chevrolet's term for a bed design in contrast to the Stepside in that there is no indentation behind the cab

Fleet vehicle: Any motor vehicle a company owns or leases that is in the normal operations of a company. Vehicles which are used in the normal operation of a company, but are owned by company employees are not fleet vehicles. If a company provides services in addition to providing natural gas, only those vehicles that are used by the natural gas provider portion of a company should be counted as fleet vehicles. Vehicles that are considered off-road (e.g., farm or construction vehicles) or demonstration vehicles are not to be counted as fleet vehicles. Fleet vehicles include gasoline/diesel powered vehicles and alternative-fuel vehicles.

Flex arm suspension: Rear axle design with torsionally flexible axle beam in line with the rear wheels and trailing links

Flex disc: Flex disc

Similar to Flexible coupling, but the term Flex Disc is used in Mercedes documentation to specify the flexible coupling at both ends of the driveshaft.

Flexibility

Elasticity of a material.
The ability of an engine to go down to low speeds in a high gear and pull away smoothly without gearing down, which is governed mainly by its torque characteristics

Flexible

The ability to bend without breaking.
The ability of an engine to go down to low speeds in a high gear and pull away smoothly

Flexible brake pipe: A pipe connecting the wheel cylinder to the rest of the system, which has to flex to allow for the up and down movement of the wheel

Flexible coupling: A simple shaft coupling used where only small angles of misalignment between the two shafts occur, as in a steering column, the drive being transmitted either by tension-stressed fabric discs or pressurized rubber blocks

Flexible drive: A drive consisting of a cable in an outer sheath, used for mainly light applications such as speedometers, rev counters and windshield wipers

Flexible drive handle: A socket drive tool with a pivoting head for use with sockets, its length gives good leverage and access to difficult locations because of its ability to bend

Flexible duct: A duct that can be routed around obstacles by bending it gradually.

Flexible fuel vehicle

A vehicle that can operate on

alternative fuels (such as M85 or E85)
100-percent petroleum-based fuels
any mixture of an alternative fuel (or fuels) and a petroleum-based fuel.

Flexible fuel vehicles have a single fuel system to handle alternative and petroleum-based fuels. Flexible fuel vehicle and variable fuel vehicle are synonymous terms.

Flexicoking: A thermal cracking process which converts heavy hydrocarbons such as crude oil, tar sands bitumen, and distillation residues into light hydrocarbons. Feedstocks can be any pumpable hydrocarbons including those containing high concentrations of sulfur and metals.

Flexural: A word referring to bending

Flexural shock: A sharp shock when bending, which can break plastics

Flexure: Bending.

Also See
Stiffness under flexure

Flickability: The ease with which the bike can be leaned to the right or left around turns. High flickability means it leans quickly and easily, acting like a sportbike. Low flickability is how a cruiser handles -- not really designed for fast riding through the canyons. Lighter, smaller bikes are generally more flickable through turns.

Flip flop: Trucker slang for a trucker's return trip as in "I'll catch you on the flip flop."

Flipper strip: See
td> Ply turnup.

Flip-top filler cap: A quick-release filler cap, as fitted to some sports and racing cars

Flitch plate: A reinforcing plate for chassis members or wheel arches

Float

A small hollow tank which is more buoyant than the liquid in which it is immersed. In a Carburetor it operates the valve (Needle and seat) which controls the amount of fuel entering the Carburetor. In the Fuel tank, it indicates the amount of fuel. Older floats were hollow and made of metal, but newer ones were made of a solid synthetic material.
The action of the Breaker arm when it is pushed out as the cam strikes the rubbing block; and before the arm can return after the cam has passed, the next cam strikes the block and re-opens it. In other words, the breaker arm never has the time to fully close before being opened again.
The action of a component to move freely because it is not firmly attached.

Also See
Full floating axle
Fully floating axle
Three-quarter floating axle
Floating piston pin
Floating frame
Floating cam
Floating caliper
Floating drum End float
Valve float

Floatation: The ability to float generally referring to large low pressure tires (i.e., the ability of a tire, to pass over soft surfaces without sinking in.)

Float bowl: That part of a Carburetor that acts as a reservoir for Gasoline and in which the float is placed. The float controls the amount of fuel moving through the fuel valve.

Float bumper spring: A small spring installed under the float tang to minimize float bounce and vibration

Float chamber: British term for Float bowl

Floating: See
Full floating axle
Fully floating axle

Floating axle: See
Full floating axle
Fully floating axle
Three-quarter floating axle

Floating caliper: A single piston caliper which moves (floats) when the brakes are applied.

Floating caliper disc brake: A disc brake with a single piston, in which the caliper itself can move to bring both pads into contact with the disc

Floating cam: Brake cam or other type of expander which is not rigidly mounted in the brake backplate of a drum brake, so that it can exert equal pressure on the two shoes

Floating drum: A brake drum that is not secured to a hub

Floating frame: A frame which holds the cylinder assembly and is supported by the mounting frame, usually made of heavy-gauge sheet steel.

Floating piston: A secondary piston

Floating piston pin: A Piston pin which is not locked in the Connecting rod or the Piston, but is free to turn or Oscillate in both the Connecting rod and the piston.

Float level

Height of the fuel in the Carburetor Float bowl.
The specific float setting that will produce the correct fuel level.
The float position at which the float needle closes against its seat, shutting off the fuel inlet valve to prevent further deliver of fuel

Float needle: A needle in the Carburetor which is activated by the level of fuel in the Float bowl. As the level drops, the needle lifts and allows more fuel to enter the bowl

Float valve: Type of valve which is operated by sphere or pan which floats on liquid surface and controls level of liquid.

Flood

To allow too much fuel to enter the Carburetor or the engine.
A condition where the fuel mixture is overly rich or an excessive amount has reached the Cylinders. Starting will be difficult and sometimes impossible until the condition is corrected.

Floodable length: The length of ship which may be flooded without sinking below her safety or margin line. The floodable length of a vessel varies from point to point throughout her length and is usually greatest amidships

Flooded engine: An engine which has too much fuel into the cylinders. It can be caused from trying to repeatedly start a car which refuses to start. If this condition continues, the engine oil could become diluted and should be changed.

Flooded evaporator: Evaporator containing liquid Refrigerant at all times.

Flooded system: Type of refrigerating system in which liquid Refrigerant fills most of the evaporator.

Flooded system, high-side float: Refrigeration system which has a float operated by the level of the high-side liquid Refrigerant.

Flooded system, low-side float: Refrigerating system which has a low-side float Refrigerant control.

Flooding

A condition where the fuel mixture is overly rich or an excessive amount has reached the Cylinders. Starting will be difficult and sometimes impossible until the condition is corrected.
Act of allowing a liquid to flow into a part of a system.
A term which refers to overcharging the system

Also See
Hot-wax flooding
Hot-wax flooding unit

Flooding unit: See
td> Hot-wax flooding unit

Flood the carburetor

An undesirable condition which occurs when the float in the Carburetor is set too high.
A desired condition which allows extra fuel into older or simpler Carburetors by pushing down the float with an extra lever (called a tickler) to give a richer mixture for starting

Floor

The flat base panel of a vehicle.
A verb meaning to push the Accelerator as far as it will go (i.e., to the floor).
The vertical transverse plate immediately above the bottom shell plating, often located at every frame, extending from bilge to bilge.

Also See
Four-on-the-floor
Four on the floor
Load floor
Load floor extension

Floorboard: The flat base panel of a vehicle. Originally it was the collection of wood planks which made up the floor of vehicle. The floor of the vehicle under the Instrument panel.

Floor change

A gear shifter on the floor -- usually on the center console.
Some coins left on the floor after being negligently dropped there.

Floor extension: See
td> Load floor extension

Floor gearchange: A gear shifter on the floor -- usually on the center console.

Floor jack: Floor jack

A device for lifting the vehicle, or part of the vehicle, off the ground to facilitate repairs. It has wheels to allow it to move to the best location and is activated by hydraulic pressure as the long arms are inserted and pumped up and down.

Floor pan

The metal structure on the bottom of the car. Almost all newer cars are unit body (or unibody) construction, and the floor pan provides the foundation for chassis stiffness. Your feet usually rest on a floor pan when you are in a car.
The large stamped metal part of the car's body over which the carpet is laid. Usually assembled from several smaller Stampings, the floorpan forms the floor and fixes the dimensions for most of the car's external and structural panels. It is also the foundation for many of the car's mechanical parts.

Floorpan: See Floor pan

Floor pump: Floor pump

A manual device for filling up pneumatic tires.

Floor shift: When the shifting lever is placed in a vehicle, it usually occupies one of three primary positions the Dash (usually a Pushbutton arrangement); the Steering column; and on the center column between the Driver and front seat passenger.

Also See
Gearshift

Floor shifter: A gear shifter on the floor -- usually on the center console.

Flow

The passing of liquid or current through something.
The amount of liquid or current conveyed.

Also See
Airflow
Electron flow
Full flow filter
Full flow oil filter
Gas flow
L-Jetronic air flow meter
Partial flow filter
Rotary flow
Vortex flow

Flow check piston: Piston assembly, with an orifice in the center, which can operate as an expansion valve.

Flow control: The regulation of the amount of fluid passing through a pump, especially important under changing operating conditions

Flow detachment: The deviation of the gas flow into the cylinder from its ideal path, thus losing its stability, caused by swirl and/or improper combustion chamber design etc.

Flow filter: See
td> Full flow filter
Partial flow filter

Flowmeter: A meter indicating the amount of liquid passing through, used for instance to supply information to a fuel consumption indicator.

Also See
Air flow meter
L-jetronic air flow meter

Flow meter: Instrument used to measure velocity or volume of fluid movement.

Flow oil: See
td> Full flow oil filter

Flow oil filter: See
td> Full flow oil filter

Flow rate: The amount of liquid conveyed by a pump per unit of time

Flow scavenging: See
td> Transverse flow scavenging
Unidirectional flow scavenging

Flow through ventilation: See
td> Flow-through ventilation.

Flow-through ventilation: A system which allows (or even forces) outside air into the passenger compartment through the Dash and leaves through openings in one of the pillars (usually the C-post) or rear quarter panels.

FLS: Acronym for Fluid Level Sensor (GM)

Flue: A gas or air passage which usually depends on natural convection to cause the combustion gases to flow through it. Forced convection may sometimes be used.

Flue gas: A product of combustion plus excess air in the Appliance flue or heat exchanger.

Flue gas baffle: An object in the path of the flue gases and exposed to flue gases or radiant heat, which is intended to restrict or modify flue gas flow. It may be a projection from the heat exchanger or suspended in the flue gas passages by some other means.

Flue gas desulfurization: The action of removing sulfur oxides from the combustion gases of a boiler plant before discharging to the atmosphere. Also referred to as scrubbing. Chemicals such as lime are used as scrubbing media.

Flue-gas desulfurization unit: Equipment used to remove sulfur oxides from the combustion gases of a boiler plant before discharge to the atmosphere. Chemicals such as lime are used as the scrubbing media. Also called a scrubber.

Flue-gas particulate collector: Equipment used to remove fly ash from the combustion gases of a boiler plant before discharge to the atmosphere. Particulate collectors include electrostatic precipitators, mechanical collectors (cyclones), fabric filters (baghouses), and wet scrubbers.

Flue outlet: The opening provided in gas utilization equipment for the escape of the flue gases.

Fluid

A substance which flows, e.g., a liquid or a gas.
Substance in either a liquid or gaseous state; substance containing particles which move and change position without separation of the mass.
Any liquid or gas that is capable of flowing and that changes its shape at a steady rate when acted upon by a force tending to change it shape. A term used to refer to any substance having the above properties.

Also See
Automatic transmission fluid
Battery fluid
Brake fluid
Easing fluid
Hydraulic fluid
Releasing fluid
Silicone brake fluid
Transmission fluid
Washer fluid
Windshield washer fluid

Fluid capacities: The full amount of oil in the Crankcase; water in the radiator and cooling system; or fuel in the gas tank; washer fluid in the reservoir tank; etc.

Fluid catalytic cracking: The refining process of breaking down the larger, heavier, and more complex hydrocarbon molecules into simpler and lighter molecules. Catalytic cracking is accomplished by the use of a catalytic agent and is an effective process for increasing the yield of gasoline from crude oil. Catalytic cracking processes fresh feeds and recycled feeds.

Fluid clutch: A hydraulically acting coupling by which power can be transmitted, used as an automatic Clutch with a driving and a driven Rotor revolving in oil which acts as the transmission medium

Fluid coking: A thermal cracking process utilizing the fluidized-solids technique to remove carbon (coke) for continuous conversion of heavy, low-grade oils into lighter products.

Fluid coupling: Fluid coupling

On a Manual transmission, there is a mechanical connection between the engine and Transmission through the Clutch. On an Automatic transmission a fluid coupling provides a Viscous fluid to connect the engine output and the transmission. It transfers engine Torque to the transmission Input shaft through the use of two units with Vanes (called a Torus") operating very close together in a bath of oil. The engine drives one torus causing it to throw oil outward and into the other torus which then begins to turn the transmission Input shaft. A fluid coupling cannot increase Torque above that produced by the Crankshaft. Buick's Dynaflow is an example of this kind of coupling.

Fluid flywheel: A kind of fluid coupling in which the flywheel is the driving Rotor

Fluid level warning indicator: A warning light on the instrument panel which is illuminated when the level of fluid in the a system is too low

Fluid reservoir: See
td> Brake fluid reservoir

Fluorescent: Having the property of giving off light when bombarded by electrons or radiant energy

Fluorescent lamp: A glass enclosure in which light is produced when electricity is passed through mercury vapor inside the enclosure. The electricity creates a radiation discharge that strikes a coating on the inside surface of the enclosure, causing the coating to glow.

Fluorocarbon: Any of a class of compounds produced by substituting fluorine for hydrogen in a hydro-carbon and characterized by great chemical stability. Fluorocarbons have numerous industrial applications, such as dichlorodifluoromethane or R-12

Flush

To cleanse a system by sending water or other liquid through a system.
To align two items so that they fit evenly or level.
Operation to remove any material or fluids from refrigeration system parts by purging them to the atmosphere using Refrigerant or other fluids.
The removal of solid particles and sludge such as metal flakes or casting flash, dirt or oil by running a pressurized cleaning solution through components and refrigerant lines

Also See
Reverse flush

Flush deck ship: A ship constructed with upper deck extending throughout her entire length without a break or a superstructure, such as forecastle, bridge or poop

Flushing

To cleanse a system by sending water or other liquid through a system.
Removing old brake fluid from a hydraulic brake system by pumping new brake fluid through the system.

Also See
Brake flushing
Flushing the cooling system
Brake flushing

Flushing tee: A device with three hose necks laid out in the shape of the letter T that is spliced into a heater hose, secured with hose clamps. the neck on the stem is covered with a threaded cap, which is removed and a household water hose is attached (with a special adapter) to run water though the cooling system to flush out dirt, rust, etc. from the engine.

Flushing the brakes: See
Brake flushing

Flushing the cooling system: The process of circulating water through the Cooling system to remove old Coolant along with any dirt or rust. Back flushing means circulating the water from the engine to the Radiator (reversing the normal direction of flow) in order to clean the system more efficiently.

Also See
Reverse flush

Flushing oil: A thin oil used to clean out the sump, oil passageways, etc.

Flush mounted speaker: A radio or stereo speaker mounted in a cutout in the interior trim so that it does not project out. The opposite of surmounted speakers.

Flute: A Groove in a cutting tool that forms a passageway for the exit of chips removed during the cutting process.

Flutter: The rapid movement of engine valves.

Also See
Bounce
Piston ring flutter
Wheel flutter

Flux

The lines of magnetic force moving through a Magnetic field.
the magnetic field that is established around an energized conductor or permanent magnet
An ingredient placed on metal being Soldered or Brazed, to remove and prevent the formation of surface oxidization which would make soldering or Brazing difficult. Flux promotes the fusion of metals during the welding process.

Flux, magnetic: Lines of force of a magnet.

Flux material: A substance used to promote fusion, e.g., of metals or minerals.

Fly: See
Shift on the fly

Flyer: A fast lap

Flying bridge: The platform forming the top of the pilot house

Flylead: A short electrical wire with a terminal at each end connect to a component

Fly nut: A wing nut.

Flyweight: See
Flyweights

Flyweights: Special weights which react to Centrifugal force to provide automatic control of other mechanisms such as Accelerators or valves.

Flywheel: Flywheel

A relatively large and heavy metal wheel that is attached to the back of the Crankshaft to smooth out the firing impulses. It provides Inertia to keep the Crankshaft turning smoothly during the periods when no power is being applied. It also forms a base for the Starter Ring gear and, in Manual transmission, for the Clutch assembly.

Also See
Engine flywheel
Fluid flywheel

Flywheel generator: A small alternator of the rotating magnet type attached to one end of the crankshaft and spinning with it, acting as an additional flywheel; now used only in mopeds or scooters

Flywheel magneto: A magneto mounted in the flywheel of a small engine, often a two-stroke

Flywheel puller: A specially designed tool with three arms and a center stud used to removing the flywheel. The three arms are attached to three mounting points (either on the rim of the flywheel or into three threaded holes in the flywheel). The center stud is screwed into the center of the flywheel and pushes against the end of the crankshaft. As the stud pushes in, the flywheel is forced away from the crankshaft.

Flywheel ring gear: A gear on the outer circumference of the Flywheel. The Starter drive gear engages the Ring gear and Cranks the engine.

Flywheel turner: A special tool used for hand cranking the engine while working on Clutches, gearboxes, etc. or doing jobs that require that the crankshaft be in a specific position. It consists of a handle and lever to hook into the starter ring teeth