Car Repair Manuals

DICTIONARY OF AUTOMOTIVE TERMS - 'Ha'

H
  1. A letter rating for tires to indicate that they are theoretically rated for speeds up to 210 kph (130 mph), as in P185HR13. The next higher rating is V and the one lower rating is T.
  2. Système International (SI) symbol for Henry
  3. Symbol for Hydrogen
H2O
Abbreviation for Water
Habits
HAC
Abbreviation for High Altitude Compensator
Hackney Carriage
Black taxis in London.
Hacksaw
Hacksaw

Hacksaw

A tool for cutting metal, with a narrow blade attached to a frame
HAI
  1. Abbreviation for Heated air inlet system
  2. Abbreviation for hot air intake
Hair
Hairline crack
A tiny stress crack which forms due to strains in the material or extreme temperature differences; as opposed to crazing, a single crack of this type will often occur alone
Hair pin
Hair pin

Hair pin

A roadway with several sharp turns usually on an hill.
Hair pin cotter
Hair pin cotter

Hair pin cotter

A securing device shaped somewhat like a U in which the legs have a series of waves or bends. Insert one leg into the hole of a rod so that the bent leg will encircle the rod.
See
Hairpin valve spring
A valve spring formed from a wire or metal strip bent to form two levers emanating from a half-loop or coil; used on some classic cars and motorcycles
HAIS
Abbreviation for Heated Air Intake System (Chrysler)
Half
Half dog point
The same as a dog point but half as long; used on short screws for the same purposes as the dog point, but in a shallower hole or slot.
Half dog point socket set screw
A headless socket set screw threaded the entire length. It has a hexagonal drive at one end and a protruding tip with a flat surface at the other end.
Half-life
Half link
Half link

Half link

Every chain has rollers which are connected by side plates or Keepers. When counting the number of links in a length of chain, it is easiest to count the number of side plates on one side of the chain and multiplying the number by two. When a chain needs to be an odd number, a half link is included. The term half link is a misnomer. It should be called a single link. The side plate on a half link is not flat but has a step down shape. For this reason, it is called an offset link.
Half moon key
Half-moon key
Half-moon key

Half-moon key

A driving key serving the same purpose as the regular key but it is shaped somewhat like a half circle. Also called a Woodruff key.
Half-moon slip joint pliers
A multiple-slip joint pliers with groove joint
Half-round body file
A body file with domed file surface for working reverse-crowned panels
Half-round file
A special file that's flat on one side and convex on the other
Half shaft
A rotating shaft that transmits power from the final drive unit to one side of the drive wheels, but usually refers to the two shafts that connect the road wheels to the final drive with Independent rear suspension or Front-wheel drive as opposed to the axle shafts of a live rear axle. Also called an Axleshaft
Half step gearing
Half-step gearing
A Gearing system of a bicycle in which a shift between chainrings in a double chainring set is equivalent to half a gear step on the freewheel.
Halftrack
Halftrack

Halftrack

Vehicle with caterpillar tracks over the rear wheels to provide motive power but steered by normal front wheels
Half wave rectifier
A rectifier which blocks one-half of an ac sine wave to convert ac into dc.
See
Half-wave rectifier
A rectifier which blocks one-half of an ac sine wave to convert ac into dc.
See
Halide Lamp
Halide refrigerants
Family of refrigerants containing halogen chemicals.
Halide torch
Type of torch used to safely detect halogen refrigerant leaks in system.
Hall effect
In electrical conductors where electric current flows perpendicular to a magnetic field, a so-called Hall voltage is produced perpendicular to the direction of current flow and to the magnetic field
Hall-effect ignition system
Transistorized ignition with Hall generator
Hall-effect sensor
A Hall generator
Hall-effect switch
A Hall vane switch
Hall element
A pulse generator that makes use of the Hall effect and consists of a rotor with vanes, a conductive element with a permanent magnet and the Hall IC. Also called Hall generator. When the air gap is unobstructed, a Hall voltage is generated; when a vane stands in the air gap, the magnetic flux cannot reach the Hall IC. Hall generators used as ignition pulse generators have as many vanes and Hall windows as the engine has cylinders, dwell being determined by the width of the vanes. Hall generators used in electronic-map ignition systems to provide the engine starting signal have only one Hall window
Hall generator
A pulse generator that makes use of the Hall effect and consists of a rotor with vanes, a conductive element with a permanent magnet and the Hall IC. Also called Hall element.
Hall IC
A solid state device with the actual Hall generator and integrated circuits for voltage amplification and potential reversal, producing the pulses for the control unit
Hall module
A Hall IC
Hall sensor
A Hall generator.
Hall vane switch
A switch that makes use of the Hall effect. When the air gap is free, a magnetic field acts on the Hall IC and the Hall voltage reaches its maximum (high). When a rotor vane obstructs the air gap, shielding the Hall IC from the magnetic flux, the Hall voltage reaches its minimum (low). The signal produced is a square wave
Hall voltage
Halo car
An automobile intended to stimulate interest in or lend prestige to an automobile line. Example: The Viper is a halo car for Dodge.
Halogen
One of the chemical elements fluorine, chlorine, bromine, iodine, or astatine.
Halogenated substances
A volatile compound containing halogens, such as chlorine, fluorine or bromine.
Halogen bulb
A quartz light bulb with a tungsten filament surrounded by a trace of a halogen gas, such as iodine, bromine, fluorine, chlorine, astatine. A halogen bulb gives off a brighter light than conventional bulbs.
Halogen headlamps
Tungsten-halogen bulb used in sealed beam unit or as separate bulb in composite headlamp
Halogen headlight
High intensity reflector with inner halogen bulb, precision lens, and 3-prong attachment. Don't touch the glass of a halogen bulb with your fingers. The oil left on the glass will cause the glass to break or reduce the life of the bulb. If the glass is accidentally touched, it may be cleaned with methylated spirits or rubbing alcohol on a soft cloth
Halogen lamp
A type of Incandescent lamp that lasts much longer and is more efficient than the common incandescent lamp. The lamp uses a halogen gas, usually iodine or bromine, that causes the evaporating tungsten to be redeposited on the filament, thus prolonging its life.
Halogens
Substance containing fluorine, chlorine, bromine, and iodine.
Hamlin switch
A suspended-mass-type sensor used in new air bag systems; avoids the ecological problems associated with the earlier mercury-type switches
Hammer
  1. To hit with a hammer.
  2. To ride hard and fast.
  3. Someone who rides hard and fast.
  4. Trucker slang for the accelerator pedal as in 'When we get past this parking lot we can really hit the hammer.'
  5. A hand tool with a head (usually metal) and a handle. It is used to force one item against or through another. Several types of hammers are available
Hammer down
Trucker slang for driving fast as in 'We got a southbound smokey with the hammer down'.
Hammer drill
Electric hand drill that hammers as well as rotates
Hammerform
A shaped wooden block used in panel beating, on which a desired form is produced by hammering
Hammer welding
Metalworking technique that includes gas welding, preferably without the use of filler rod, followed by hammer and Dolly work on the welded joint to smooth out any remaining imperfections
Hand
Handbook
A manual which gives instructions or information.
Handbrake
A brake operated by a hand lever. It may also refer to the Parking brake.
Handbrake turn
180° turn achieved by applying the handbrake (acting on the rear wheels) hard when the vehicle is starting to turn
Handbrake warning light
A light on the instrument panel that illuminates when the handbrake is applied; on most new cars it has been superseded by a multifunction brake warning light
Hand controls
An auxiliary set of components to allow disabled people to operate a vehicle.
Hand Crafted
Something that is built by hand rather than in an assembly line (i.e., mass produced).
Hand crank
Before Cadillac invented and first produced electric starters, engines were started by means of a handle which was inserted into the front of the engine and rotated manually. After 1930 it became obsolete.
Hand cycle
Hand cycle

Hand cycle

A human powered cycle that is propelled by rotating the crank with your hands rather than your feet. Usually there is one wheel up front and two (often smaller) in the back. It is designed for people who are unable to use their legs.
Hand drill
Hand drill

Hand drill

A power-driven device for boring holes or (with the correct attachment) removing or securing screws and bolts
Handed
Something that is made for a specific side of a unit. For example, left hand arm rests are not interchangeable with right hand arm rests.
Hand file
A flat File for shaping metal, with a rectangular cross section, constant blade width and one smooth edge
Hand gear
Hand gear lever
Handivan
A large van designed for transporting disabled people and their wheelchairs. See Invalid-carriages
Hand lapped valves
A process of grinding valves by hand so that there is a perfect match between the valve and its seat.
Handle
  1. The reaction of a vehicle under a particular circumstance, especially regarding cornering, roadholding, and maneuvering.
  2. To deal with or to cope with (e.g., 'the tires can handle 50 psi' means the tires can withstand pressure up to 50 psi).
  3. A CB user's code name.
Handlebar
A steering device found on bicycles and motorcycles. Grips, brake levers, and shifters, etc. are attached to the handlebar.
Handlebar bag
Handlebar bag

Handlebar bag

A container, usually leather and nylon, which mounts on the front of a bicycle's handlebars.
Handlebar riser
A bracket which lifts the base of the handlebar up higher.
Handler
Handling
  1. The relative ability of a vehicle to negotiate curves and respond to road conditions. It is a factor of the weight of the vehicle, the suspension, tires, air flow, etc.
  2. The labor involved in moving product received from the trailer into the warehouse dock and then into the storage location on the 'IN' and moving the product out of the storage location and into a staging location to then be loaded onto a trailer on the 'OUT'. The Warehouse Forklift / Clamp Operator moves product IN and OUT. If additional handling is involved such as opening on days off, pick packing etc., that are not the normal handling as defined in the warehouse contract, these would be defined as additional accessorial charges for handling.
  3. A single pick-up, movement and set-down of a loaded or empty pallet.
Handling Charge
Charge for normal warehouse handling (inbound or outbound, or both) to customer.
Handling Costs
Cost to warehouse or 3PL for all handling operations.
Handling system
Hands
Hands-free
A car cell phone that allows the driver to dial and talk on the phone without handling the phone.
Handshaker
A colloquial term for a passenger car with a manual transmission
Hand shield
An eye and face protector held in the hand. It enables a person to look directly at the electric arc through a special lens without being harmed.
Hand thread
Hand Truck
A non-motorized device used to transport goods manually with a pair of wheels.
Hand turn
Hand turn signal
Hang a left
To make a left-turn
Hang a right
To make a right-hand turn
Hang a U-ey
To make a U-turn
Hanger
  1. A flexible ring or strap to hold a pipe, e.g., an exhaust pipe.
  2. A mounting bracket, e.g., a Spring hanger for a Leaf spring.
  3. A component of sighting point gauges, used to install the gauge at the vehicle chassis.
  4. Device attached to walls or other structure for support of pipe lines.
Hanger Bolt
Hanger bolt

Hanger bolt

A fastener where one end is gimlet pointed and has a wood screw thread. The other end consists of a coarse machine screw thread. The center section is unthreaded.
Hangover
A modification of custom cars with separate chassis, e.g., pick-ups, which raises the floorpan and lowers the body, to give the impression that the body has been pulled down over the chassis right down to street level
Hard aground
A ship which has gone aground and is not able to move under her own power.
Hard anodic coating
Hard, wear-resistant, oxide layer produced in an anodic oxidation process
Hard anodizing
A special type of anodizing adapted to the production of thick, hard, abrasion-resistant films
Hardboard
A board-like building material made of compressed wood chip fibers and sawdust
Hard chromium plating
An electrolytic deposition of a hard, wear-resistant, chromium layer
Hard code
A type of trouble code that causes the ECU to disengage the ABS and not re-engage it until the problem is repaired
Hard-dry
The condition of paint when it is hard enough to polish
Harden
  1. The action of turning from a liquid to a solid.
  2. To set or to cure.
  3. The action of making the surface a metal tougher.
Hardenability
In a ferrous alloy, the property that determines the depth and distribution of hardness induced by quenching.
Hardened
Hardened pushrods
Specially treated pushrods designed for use with pushrod-guided rocker arms
Hardened Steel Nail
A heat treated and tempered steel pallet nail with a MIBANT angle between 8 and 28 degrees.
Hardener
Chemical added to plastic filler to induce hardening as used in auto body repair.
Hardening
  1. The process of paint, epoxy, or glue becoming hard. The drying or hardening of paint film goes through several stages. The first stage is called dust-free; at this stage, the paint has hardened sufficiently to prevent dust from becoming embedded in the paint film. The second stage is called touch-dry; at this point, the paint film can actually be touched with light finger pressure. The third and final stage is referred to as hard-dry; at this point, the paint film is hard enough to polish.
  2. A method of heat treating metals by heating to a temperature within, or above, the critical range, holding at that temperature for a given time, and then cooling rapidly, usually by quenching in oil or water.
Hardening media
A liquid into which steel is immersed in order to harden the steel. Usually involves cold water, brine, oil, and special polymers.
Hardness
  1. The toughness of the surface of a metal. Normally stated in terms of Rockwell or Brinell scale of measurement, hardness shows resistance of a fastener to rough marks and abrasions, can indicate yield strength and brittleness, and has a direct relationship to tensile strength in alloy steel fasteners. However, for stainless, brass, and silicon bronze, the correlation between hardness and tensile or yield is tenuous with no definite relationship. Case-hardening uses surface heat treatment on ferrous material to cause a harder outside surface than the center. Through-hardening hardens the entire fastener. Bright hardening calls for heat treatment without oxygen, so no oxides are formed on the material surface.
  2. Resistance to plastic deformation by indentation, penetration, scratching or bending.
  3. Chain hardness is typically measured in Vickers, Brinell or Rockwell.
Hard pedal
A loss in braking efficiency so that an excessive amount of pressure is need to actuate brakes
Hard points
Specific locations, usually called out on a full-sized body draft, of points that have to be adhered to when designing surfaces. Hard points include axle centerlines, seats, pedal locations, roof and sill heights, luggage-compartment dimensions, etc.
Hard rubber
See
Hard shoulder
A part of the road that is divided by broken or continuous yellow lines from the rest of the road and should be used only by certain road users in certain situations
Hard-sided caravan
A British term for a trailer with foldable, hard wall panels
Hard-sided trailer
A trailer with foldable, hard wall panels
Hard solder
Uniting two pieces of metal with a material having a melting point higher than soft solder e.g., silver soldering
Hard spots
Shiny bluish/brown glazed areas on a brake drum or disc friction surface, caused by extreme heat. Excessive heat has changed their molecular structure. Hard spots can usually be removed by resurfacing
Hard stop
Hard braking, but not necessarily with locked wheels
Hardtail
A term for a bike (motorcycle or bicycle) which has no rear suspension
Hardtop
Hardtop
Hardtop
  1. A two-door or four-door vehicle without a center door post, i.e., no B-post. It gives the impression of uninterrupted glass along the side of the car. The term is derived from hardtop convertible. Other generic names have included sports coupe, hardtop coupe, or pillarless coupe. In the face of proposed rollover standards, nearly all automakers turned away from the pillarless design to a pillared version by 1976-77.
  2. A removable top made from fiberglass or steel that replaces the soft-top. It is usually painted the same color as the body of the car.
Hardtop convertible
  1. An automobile with a fixed roof that does not retract into the trunk, but gives the appearance of being a convertible because it does not have B-pillars
  2. A type of convertible having a removable hard top. Such designs include tops that unfasten and lift off such as early Ford Thunderbirds, Mercedes Retractable hardtop, and the retractable Fords of the late 1950's.
Hardtop stand
A foldable stand that holds a detached hardtop in a vertical position when stored
Hard-top trailer
Hard-top trailer

Hard-top trailer

A vacation trailer with a hard top and (most often) canvas sides.
Hard trim
Instrument panel moldings, center consoles and similar plastic trim
Hardwood
A wood from broad-leaved species of trees (not necessarily hard or dense).
Hardy disc
A disc-style flexible coupling
Hardy-Spicer joint
A type of universal joint commonly used with prop shafts
Hardy-Spicer universal joint
A type of universal joint commonly used with prop shafts
Harley-Davidson
Harley-Davidson

Click image for books on
Harley-Davidson

A motorcycle manufacturer
Harm
Harmful
Harmonic balancer
Also called Vibration damper. It usually is a solid crankshaft Fan belt Pulley that has a weight ring bonded by rubber to the inner crankshaft-mounted ring. The outer ring absorbs and cancels out crankshaft vibrations that otherwise might cause the crankshaft to break. Formerly, two gearwheels carrying an unbalanced weight, mounted in bearings below the middle main crankshaft bearing, driven at twice engine speed and rotating in opposite directions to counterbalance the secondary vibrations in a four-cylinder reciprocating engine.
Harmonic balance wheel
A grooved wheel attached to the front end of the crankshaft which is connected by accessory belts to the fan, alternator, power steering pump, water pump, air conditioning compressor, and other devices so that the rotating crankshaft can drive these other parts as well. The crankshaft pulley usually has timing marks located on it, and these are necessary for checking and adjusting timing with a timing light.
Harmonic Distortion
Harmonic voltage
A voltage whose frequency is a multiple of the fundamental frequency.
Harness
  1. A belt system used with child seats and in cars, consisting of two shoulder belts and two lap belt portions fastened by a central buckle.
  2. A bundle of electrical wires. For convenience in handling and for neatness, all wires going to certain part of the vehicle are bundled together into a harness. A Wiring harness.
Harness Connector
Harness ties
Self-tightening nylon straps used to bundle wires into harnesses. Once tightened, they can't be removed unless they are cut
Harness wrap
One of several materials used to bundle wires into manageable harnesses
Harvey wallbanger
Trucker slang for a reckless driver as in 'That 4-wheeler is a real harvey wallbanger.'
Hat
The portion of a detachable brake disc that comes in contact with the wheel hub
Hatch
  1. The rear opening of a vehicle which allows passage into its cab.
  2. A hatchback.
  3. A tailgate.
  4. An opening in a deck through which cargo and stores are loaded or unloaded.
Hatchback
Hatchback

Hatchback

A car design in which the rear trunk and lid are replaced by a rear hatch that includes the Backlight (i.e., rear window). Usually the rear seat folds down to accommodate more luggage. Originally a hatch was a small opening in the deck of a sailing ship. The term hatch was later applied to airplane doors and to passenger cars with rear liftgates. Various models appeared in the early 1950s, but weather-tightness was a problem. The concept emerged again in the early 1970s, when fuel economy factors began to signal the trend toward compact cars. Technology had remedied the sealing difficulties. By the 1980s, most manufacturers produced one or more hatchback models, though the question of whether to call them two-door or three-door never was resolved. Their main common feature was the lack of a separate trunk. Liftback coupes may have had a different rear-end shape, but the two terms often described essentially the same vehicle.
Hatchback coupe
Hatchback coupe

Hatchback coupe

Originally a small opening in the deck of a sailing ship, the term hatch was later applied to airplane doors and to passenger cars with rear liftgates. Various models appeared in the early 1950s, but weather-tightness was a problem. The concept emerged again in the early 1970s, when fuel economy factors began to signal the trend toward compact cars. Technology had remedied the sealing difficulties. By the 1980s, most manufacturers produced one or more hatchback models, though the question of whether to call them two-door or three-door never was resolved. Their main common feature was the lack of a separate trunk. Liftback coupes may have had a different rear-end shape, but the two terms often described essentially the same vehicle.
Hatch battens
Flat bars which are wedged against hatch coamings to secure tarpaulin
Hatch beam
Portable beam across a hatch to support hatch covers
Hatch coaming
The vertical plating bounding a hatch for the purpose of stiffening the edges of the opening and resisting water entry
Hatch Cover
See Pontoon Hatch Cover.
Hatched marking
Chevron markings on the road which help separate traffic lanes
Hatchway
An opening in a deck through which cargo and stores are loaded or unloaded
Hat section
Haul
Haul Distance
Hauling
Hauling snow
The loading, removing, and disposing of snow piles after snowplowing operations
Haul road
Hawse pipe
Tube through which anchor chain is led overboard from the windlass on the deck
Hawser
Strong rope or steel cable used for towing, securing or mooring ships
Hazard
Anything that could be a source of danger on the road
Hazard flasher switch
A switch (usually located on the steering column below the steering wheel) which makes all the signal lights flash simultaneously, to warn other vehicles that your car is disabled or going very slowly down the road. Also called 4-way warning light switch.
Hazardous location
Any area or space where combustible dust, ignitable fibers, or flammable, volatile liquids, gases, vapors or mixtures are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures.
Hazardous materials
Commodities classified by the Department of Transportation as hazardous, and which require special handling and documentation. Also known as hazmat.
Hazardous material tag
A red tag attached to delivery receipts and COSOs. The tag denotes the type and amount of hazardous material in the shipment.
Hazardous wastes
Automotive wastes that are on the EPA's list of hazardous materials or that have one or more hazardous characteristics
Hazard warning flasher
Actuates warning system of flashing front and rear turn signal lamps
Hazard warning switch
A switch (usually located on the steering column below the steering wheel) which makes all the signal lights flash simultaneously, to warn other vehicles that your car is disabled or going very slowly down the road. Also called 4-way warning light switch.
Hazmat
Abbreviation for Hazardous materials, as classified by the U.S. Environmental Protection Agency (EPA). Transport of hazardous materials is strictly regulated by the U.S. Department of Transportation. Also spelled HazMat



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