A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
W
Wander: The tendency of a vehicle to drift away from the steered course when being driven. Usually associated with low or uneven tyre pressures or tight steering joints.
Wankel Engine: Rotary engine using a three-cornered rotor in a trochoidal chamber. Invented by Felix Wankel.
Warpage: Twisting or bending distortion.
Warranty: The legal rights given by manufacturers to cover possible defects occurring during a specified time or mileage.
Washer: Flat circular plate with a hole in it. Used to spread the load of a nut or bolt.
Waste Gate: Control valve in the exhaust gas flow through a turbocharger.
Water Jacket: Part of the cylinder block and head of an engine that encloses the cavity through which cooling water flows.
Water Pump: (1) Pump that circulates the water of an engine's cooling system. Also circulating pump. (2) Any pump for delivering water under pressure, as for screen washing, etc.
Water Trap: A bowl used to separate water from fuel.
Watt: Unit of power. Volts X amps.
Wattage: The power rating of an electrical device.
Wave Wound: A winding that is wound in waves instead of individual coils.
Waveform: Pattern displayed on an oscilloscope screen.
Wavelength: The distance between corresponding points of two consecutive waves.
Wax Injection: Anti-corrosion body wax injected into box sections.
Wax Pellet Actuator: A switch or valve that operates as temperature affects a wax pellet.
Wax Plugging: Formation of wax in diesel fuel at low temperatures that plugs the diesel fuel line or filter element preventing fuel flow.
Waxing: Separation of wax in diesel fuel at low temperatures.
Waxstat: A thermostat operated by wax. As wax changes state from solid to liquid, its volume changes.
Webbing: Description of the material used for seat belt straps.
Wedges: A method of increasing force by use of a taper or inclined plane.
Weight Transfer: The shift of a vehicle's weight towards the front when braking and towards the rear during rapid acceleration.
Welch Plug: A dished steel disc used as a core plug in engines and cylinder heads.
Wet Clutch: A friction clutch that runs in an oil bath.
Wet Liner: Not strictly a liner as it does not line a cylinder, but is the cylinder of a water cooled engine that fits into the cylinder block in contact with the coolant.
Wet Sump (Oil Pan): An engine lubrication system where the reservoir of lubricating oil is held in a sump below the engine. As distinct from a dry sump where the reservoir of lubricating oil is kept in a separate tank.
Wheel Alignment: The relative angle of the road wheels to the true longitudinal axis of the vehicle. The toe angle is the degree of variation needed to bring the wheels into true rolling motion when the vehicle is travelling. Also known as 'toe'.
Wheel Base: The dimension from the centre of the front axle to the centre of the rear axle(s).
Wheel Bearing: Roller or ball bearing used to support a drive shaft or a wheel on a stub axle.
Wheel Cylinder: A brake hydraulic cylinder in a drum brake. It is fitted to the back plate on the wheel axle assembly.
Wheel Hub: The centre assembly of a wheel containing the wheel bearings.
Wheel Nave: Connects the rim to the wheel hub.
Wheel Offset: The distance from the wheel nave to the centre line of the wheel. Used to accommodate the brake assembly and bring the centre line of the wheel into close alignment with the centre line of the steering swivel and wheel hub.
Wheel Plane: The plane (flat area) through the wheel at right angles to the axle.
Wheel Rim: Part of wheel that holds the tyre.
Wheel Slip (spin): Loss of friction between a tyre and the road surface allowing the wheel to spin faster than the speed of the vehicle.
Wheel Track: The dimension between the centers of the road wheels on one axle. Also known as tread.
Wheel slip (Spin): Loss of friction between a tyre and the road surface allowing the wheel to spin faster than the speed of the vehicle.
Whip (Whirl): The throw out of a rotating shaft. In relation to drive shafts whip can create unpleasant harmonics and vibrations.
White metal: Tin based alloy used as a coating for plain steel bearings.:
Whitworth: Standard size of thread. Old British standard.
Winding: Coil of wire used to create magnetism.
Windings: Coils of wire used to create magnetism when a current flows through them.
Wiring Harness (Loom): The bundle of cables that are bound together to form the electrical distribution system for a vehicle or system.
Woodruff Key: A locating device that sits in slots on a shaft and pulley or gear wheel. Also known as a half-round key or in some cases just key!
Work: Performed when energy is used. The SI unit is the '
Worm Gear: Gear set with a screw pinion driving a wheel with meshing circumferential teeth.
WOT: Wide Open Throttle. Switch or sensor.