Glossary “leakage current” Definition:
Small amount of current that flows through insulation when a voltage is present and heats the insulation due to it’s resistance, resulting in a slight power loss.
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leakdown test
Glossary “leakdown test” Definition:
A test using 100 psi air pressure injected in each cylinder via the spark-plug hole or injector port to determine the leakage past the rings, gaskets, or valves.
leaf spring bushing
Glossary “leaf spring bushing” Definition:
Bushings that are used to damped noise and vibration from the road to the frame of the car.
leaf spring center bolt
Glossary “leaf spring center bolt” Definition:
A bolt passed through a hole in the center of each spring leaf for holding the leaves together. The bolt head is used to locate the spring position on the axle housing.
leaf spring hanger
Glossary “leaf spring hanger” Definition:
The vehicle frame-attachment bracket for the front eye of the rear leaf spring that allows the spring to pivot.
leaf spring shackle
Glossary “leaf spring shackle” Definition:
The small arm, or swing attachment for the rear of the leaf spring located between the frame and spring eye. It allows the spring to shorten and lengthen during normal driving conditions.
leaf tip insert
Glossary “leaf tip insert” Definition:
Small, replaceable pads of plastic, rubber, or composition placed between spring leaves near their ends to promote slippage between the leaves during flexing.
leak detector
Glossary “leak detector” Definition:
1). A device using visual or audible signals to indicate a leak. 2). A dye-type fluid that may be injected into a system that will indicate the presence of a leak.
leading link
Glossary “leading link” Definition:
Component of the suspension system that is attached to the chassis behind the wheel and positioned to resist fore-and-aft movement of the wheel.
leading shoe
Glossary “leading shoe” Definition:
1). A brake shoe in a nonservo brake that pivots around a fulcrum in the direction of normal drum rotation. Also known as forward shoe. 2). The first shoe in the direction of drum rotation in a leading trailing brake.
leading trailing brake
Glossary “leading trailing brake” Definition:
A drum brake that develops self-energizing action only on the leading shoe. Brake application force is separate for the leading and the trailing shoes. Also called a partial-servo or a nonservo brake.
leaf spring
Glossary “leaf spring” Definition:
A rear, vehicle suspension spring, featuring one or more flat leaves of spring steel with graduated lengths. It has an “eye” at one end to connect to the vehicle frame and it is connected to the axle with a U-bolt.
lead sled
Glossary “lead sled” Definition:
A car with excessive amounts of lead or body filler over mediocre, sheet-metal work.
lead sulfate
Glossary “lead sulfate” Definition:
A hard, insoluble layer that slowly forms on the plates of a discharging battery that may be reduced only by slow charging.
leaded gasoline
Glossary “leaded gasoline” Definition:
Gasoline to which a small amount of tetraethyl lead is added to improve engine performance and reduce detonation, a practice no longer allowed due to EPA regulations.
lead peroxide
Glossary “lead peroxide” Definition:
The positive plate of an automotive battery normally composed of PbSO4
LCV
Glossary “LCV” Definition:
Load Control Valve
LD50
Glossary “LD50” Definition:
The dose that causes death in 50% of the animals exposed by swallowing a substance. A measure of acute toxicity.
LDDT
Glossary “LDDT” Definition:
Light Duty Diesel Truck
LDR
Glossary “LDR” Definition:
(Porsche) Turbo Pressure Regulation