Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Kn"

Knee, beam: Bracket between a deck beam and frame

Kneeling feature: A device that is put on a van or bus, which allows the entire right side to become lower thus offering someone who has trouble going up steps easy access to the vehicle.

Kneuter valve: This is the unknown part that causes a car's weird problems that a mechanic cannot find or repair.

Knife: See
Jack knife Putty knife

Knifing stopper: Fine grade filler for minor dents and chips

Knight: See
Stearns-Knight
Willys-Knight

KNK: Acronym for Knock sensor

Knob: See
Choke knob
Gear knob
Mixture control knob
Shifter knob
Spinner knob

Knobby: See
Knobby tire.

Knobby tire: On a Bicycle or Motorcycle, a heavy-duty tire with large rubber knobs spaced relatively far apart to provide Traction in wet, muddy terrain.

Knobby tires: See
Knobby tires.

Knock

A general term used to describe various noises occurring in an engine; may be used to describe noises made by loose or worn mechanical parts.
Preignition, or Detonation.

Also See
Anti-knock agent
Carbon knock
Diesel knock
Engine knock
Fuel knock
Spark knock

Knock additive: See
Anti-knock additive

Knockback

The action of a brake disc with excessive runout pushing back the brake pads when the brakes are not applied
Brake caliper piston retraction caused by rotor runout driving a piston back into its bore when the brakes are released.

Knock control: A device which retards the spark advance when detonation occurs. The retard mode is held for a certain time, typically 20 seconds, after which the knock control reverts to normal operation

Knocker: A colloquial term for a Panel puller

Knocking

Noise created by part movement in a loose or worn bearing.
A condition, accompanied by an audible noise, that occurs when the Gasoline in the Cylinders burns too quickly. This is also referred to as Detonation.

Knock limit: The degree of spark advance before detonation

Knock off: A single, large Wing nut for fastening a wheel to the hub. Easily removed and replaced, it is struck (knocked off) with a mallet on the wings. Also called a spinner.

Knock-off wheel: A splined-hub wheel with one central locking nut (Spinner) which is knocked on and off with a soft-headed hammer

Knock-on: A Knock off nut

Knock resistance: See
Octane number

Knock sensor: (KNK or KS) a piezoelectric accelerometer mounted on the engine to detect the high-frequency vibrations caused by detonation. Since an engine gives the best power and efficiency as it approaches detonation, the knock sensor can relay this information to a computer which can control the factors leading to detonation. Also called Detonation sensor

Knot: A unit of speed in nautical mile (6,080 feet or 1,852 meters) per hour.

Knuckle

The joint of a hinge through which the pin passes;
The hinged joint between two rods or tubes.

Also See
Ball joint steering knuckle
Steering knuckle

Knuckle angle: See
Steering knuckle angle

Knuckle arm: Steering arm.

Also See
Steering knuckle arm

Knucklehead: Term for Harley-Davidson's first overhead-valve Big Twin, introduced in 1936

Knuckle pin: See
Kingpin

Knurl

A series of small ridges on nuts and knobs to provide a grip for fingers.
To indent or roughen the finished surface of a piece of metal by pressing a series of cross-hatched lines into the surface and thereby raising the area between these lines.

Knurled nut: A thumb nut with knurled sides

Knurling: Roughening with knurls