Glossary “base ignition timing” Definition:
The number of degrees BTDC the ignition is fired without advance of any kind.
b
base coat
Glossary “base coat” Definition:
The initial layer of paint.
base coat patch
Glossary “base coat patch” Definition:
Small area on the vehicle’s surface without clearcoat that enables the painter to check for color match with tri-coat colors.
base current
Glossary “base current” Definition:
The amount of current that flows through the base-emitter section of a transistor.
base engine timing
Glossary “base engine timing” Definition:
Spark advance in degrees BTDC that provides the best combustion and power at very low RPM for starting.
barrier creams
Glossary “barrier creams” Definition:
Rubbed on the skins prior to working in a greasy environment, protects the skins and aids in clean-up.
barrier hose
Glossary “barrier hose” Definition:
A hose constructed with a special liner to prevent refrigerant leakage through its walls. Most air-conditioning systems in vehicles manufactured after 1988 have barrier-type hoses.
BART
Glossary “BART” Definition:
Best Available Retrofit Technology (emissions related)
base
Glossary “base” Definition:
1). The name for the section of a transistor that controls the current flow through the transistor. 2). The unique number of values in a numbering system; decimal has 10, binary has 2, hexadecimal has 16. 3). The opposite of an acid.
base 10
Glossary “base 10” Definition:
A base unit in the metric system. All metric units are increased or decreased in units of 10. One meter, for example, has 10 decimeters, 100 centimeters, or 1,000 millimeters.
base circle
Glossary “base circle” Definition:
The low portion of each cam on the camshaft, concentric with the journal, which is not part of the lobe.
barrel sanding block
Glossary “barrel sanding block” Definition:
Small, handheld sanding blocks of round construction that are ideal for small, isolated defect removal.
barrel shape
Glossary “barrel shape” Definition:
Brake drum having a frictional surface that is larger in the center than at the open end or the rear of the drum.
barrier
Glossary “barrier” Definition:
1). A term given to something that stands in the way, separates, keeps apart, or restricts. 2). A term for a diode or transistor junction. 3). An obstruction. 4). A refrigerant hose that uses a special lining (barrier) to prevent the loss of refrigerant throuigh through the hose material.
barrel faced ring
Glossary “barrel faced ring” Definition:
A compression piston ring with a rounded contact face.
barrel finish
Glossary “barrel finish” Definition:
The rounded surface on a piston skirt.
BARO V
Glossary “BARO V” Definition:
Barometeric Pressure Signal Voltage Displayed in Volts.
barometer
Glossary “barometer” Definition:
An instrument used for measuring barometric pressure.
barometric pressure (BARO)
Glossary “barometric pressure (BARO)” Definition:
The pressure exerted by the weight of the earth’s atmosphere, equal to one bar, 99.97 kPa, or 14.5 psi at sea level. Barometric pressure changes with the weather and with altitude. Since it affects the density of the air entering the engine and ultimately the air/fuel ratio, some computerized emissions-control systems use a barometric pressure sensor so that the spark advance and (EGR) valve flow can be regulated to control emissions more precisely.
barometric pressure sensor
Glossary “barometric pressure sensor” Definition:
Senses barometric pressure and sends an electrical signal to the for optimum engine control.