Chapter 1 Routine maintenance and servicing

REF•22 Glossary of technical termsAABS (Anti-lock brake system) A system,usually electronically controlled, that sensesincipient wheel lockup during braking andrelieves hydraulic pressure at wheels that areabout to skid.Air bag An inflatable bag hidden in thesteering wheel (driver’s side) or the dash orglovebox (passenger side). In a head-oncollision, the bags inflate, preventing thedriver and front passenger from being thrownforward into the steering wheel or windscreen.Air cleaner A metal or plastic housing,containing a filter element, which removesdust and dirt from the air being drawn into theengine.Air filter element The actual filter in an aircleaner system, usually manufactured frompleated paper and requiring renewal at regularintervals.Air filterAllen key A hexagonal wrench which fits intoa recessed hexagonal hole.Alligator clip A long-nosed spring-loadedmetal clip with meshing teeth. Used to maketemporary electrical connections.Alternator A component in the electricalsystem which converts mechanical energyfrom a drivebelt into electrical energy tocharge the battery and to operate the startingsystem, ignition system and electricalaccessories.Alternator (exploded view)Ampere (amp) A unit of measurement for theflow of electric current. One amp is theamount of current produced by one voltacting through a resistance of one ohm.Anaerobic sealer A substance used toprevent bolts and screws from loosening.Anaerobic means that it does not requireoxygen for activation. The Loctite brand iswidely used.Antifreeze A substance (usually ethyleneglycol) mixed with water, and added to avehicle’s cooling system, to prevent freezingof the coolant in winter. Antifreeze alsocontains chemicals to inhibit corrosion andthe formation of rust and other deposits thatwould tend to clog the radiator and coolantpassages and reduce cooling efficiency.Anti-seize compound A coating thatreduces the risk of seizing on fasteners thatare subjected to high temperatures, such asexhaust manifold bolts and nuts.Asbestos A natural fibrous mineral with greatheat resistance, commonly used in thecomposition of brake friction materials.Asbestos is a health hazard and the dustcreated by brake systems should never beinhaled or ingested.Axle A shaft on which a wheel revolves, orwhich revolves with a wheel. Also, a solidbeam that connects the two wheels at oneend of the vehicle. An axle which alsotransmits power to the wheels is known as alive axle.Axleshaft A single rotating shaft, on eitherside of the differential, which delivers powerfrom the final drive assembly to the drivewheels. Also called a driveshaft or a halfshaft.BAnti-seize compoundAxle assemblyBall bearing An anti-friction bearingconsisting of a hardened inner and outer racewith hardened steel balls between two races.BearingBearing The curved surface on a shaft or in abore, or the part assembled into either, thatpermits relative motion between them withminimum wear and friction.Big-end bearing The bearing in the end ofthe connecting rod that’s attached to thecrankshaft.Bleed nipple A valve on a brake wheelcylinder, caliper or other hydraulic componentthat is opened to purge the hydraulic systemof air. Also called a bleed screw.Brake bleedingBrake bleeding Procedure for removing airfrom lines of a hydraulic brake system.Brake disc The component of a disc brakethat rotates with the wheels.Brake drum The component of a drum brakethat rotates with the wheels.Brake linings The friction material whichcontacts the brake disc or drum to retard thevehicle’s speed. The linings are bonded orriveted to the brake pads or shoes.Brake pads The replaceable friction padsthat pinch the brake disc when the brakes areapplied. Brake pads consist of a frictionmaterial bonded or riveted to a rigid backingplate.Brake shoe The crescent-shaped carrier towhich the brake linings are mounted andwhich forces the lining against the rotatingdrum during braking.Braking systems For more information onbraking systems, consult the HaynesAutomotive Brake Manual.Breaker bar A long socket wrench handleproviding greater leverage.Bulkhead The insulated partition betweenthe engine and the passenger compartment.CCaliper The non-rotating part of a disc-brakeassembly that straddles the disc and carriesthe brake pads. The caliper also contains thehydraulic components that cause the pads topinch the disc when the brakes are applied. Acaliper is also a measuring tool that can be setto measure inside or outside dimensions of anobject.1595 Ford Fiesta Remake