DEFINITION OF TERMS-CONTINUED
BBDC. Before bottom dead center.
Bond. To bind together.
Bore. The diameter of an engine cylinder hole.
BDC. Bottom dead center; the position of the piston
Also, the diameter of any hole; as, for example, the hole
when it reaches the lower limit of travel In the cylinder.
into which a bushing is fitted.
Bead. The circular wire-reinforced section of a tire that
Boss. An extension or strengthened section, such as the
Joins with the wheel rim.
projections within a piston which supports the piston pin.
Bearing. A part In which a Journal pivot, or pin, turns or
Bottled Gas. A gas that remains a liquid when confined
revolves. A part on or In which another part slides.
In a tank under pressure.
Bendix Drive. A type of drive used in a starter that
Bound Electrons. Electrons located in the Inner orbits
provides automatic coupling with the engine flywheel for
around the nucleus of an atom.
cranking and automatic uncoupling when the engine
Bourdon Tube. A hollow circular-shaped tube used as
the pressure-sensing element in some gages.
Bevel Gear. One of a pair of meshing gears whose
working surfaces are inclined to the centerlines of the
Brake Anchor. A steel pin-shaped stud, rigidly mounted
driving and driven shafts.
to the backing plate, upon which the brakeshoe either is
attached or rests against.
Bezel. A device used to attach a glass face to an
Brake Backing Plate. A rigid steel plate upon which
certain brake components are attached.
Blackout Lights. A lamp Installed on a vehicle for use
during blackouts, which can be seen from the air only at
Brake Band. A flexible band, usually of metal with an
very close range.
Inner lining of brake fabric, that is tightened on a drum to
slow or stop drum rotation.
Block. See Cylinder Block.
Brake, Disk-Type. A braking network consisting of a
Blowby. Leakage of the compressed fuel-air mixture or
rotating disk that is restrained during application by
burned gases from combustion, passing piston and
stationary brake pads mounted on both sides of the disk.
rings, and into the crankcase.
Brakedrum. A metal drum mounted on a car wheel or
Blower. A mechanical device for compressing and
other rotating members; brakeshoes or brake band,
delivering air to engine at higher than atmospheric
mechanically forced against it, cause it to slow or stop.
Brake Fade. A reduction in the coefficient of friction
The assembly of sheet metal sections,
between retarding members as a result of excessive
framework, doors, windows, etc, which provides an
enclosure for passengers or carriage space for freight.
Brake Fluid. A compounded fluid used in hydraulic
Bogie. A suspension unit consisting of tandem axles
braking system; it transmits hydraulic force from the
jointed by a single cross support (trunnion axle) that also
brake master cylinder to the wheel cylinder.
acts as a vertical pivot for the entire unit.
Brake Horsepower. The power actually delivered by the
Boiling Point. The temperature at which a liquid boils.
engine that is available for driving the vehicle.
Change 1 A-3