Glossary “pressure tank spray gun” Definition:
Similar to the pressurized pot, except it uses a much larger storage container for paint material.

Glossary “pressure test” Definition:
Procedure for testing the entire cooling system for leaks. Or, a test to tell if the A/T is experiencing internal leakage or requires adjustment to the linkage or vacuum modulator. May also refer to the pressure applied to an evaporative emission system to check for leaks. This would be used to perform an evaporative system integrity test.

Glossary “pressure tester” Definition:
Device used to pressure test the cooling system and pressure cap. Can also refer to any piece of equipment that is used to externally apply a pressure to a system, for the purpose of testing its integrity.

Glossary “pressure relief valve” Definition:
1). A valve held closed by a spring or other means, which automatically relieves pressure in excess of its setting. 2). Carburetor fuel bowl vent operated by vapor pressure from evaporated fuel. 3). AIR system valve that functions to relieve pump-output pressure that exceeds a predetermined amount. 4). Valve in an engine oil pump having a calibrated spring working against a moveable plunger or ball to regulate maximum oil pressure.

Glossary “pressure switch” Definition:
Electrical switch that is actuated by a predetermined low or high pressure.

Glossary “pressure regulator” Definition:
1). Device that operates to prevent excess pressure buildup in a system. 2). A valve in some automatic transmissions that opens to release oil from a line when the oil pressure reaches a specific maximum limit.

Glossary “pressure release grill” Definition:
An air vent that prevents pressure from building up inside the car; while the air-conditioning system is operating, or the door is closed rapidly.

Glossary “pressure relief groove” Definition:
Small groove cut in the piston-ring land between the grooves for the compression and oil rings to equalize combustion pressures between them.

Glossary “pressure reduction” Definition:
Drop of pressure due to a restriction or metering device.

Glossary “pressure line” Definition:
1). Term that generally refers to the discharge line of an air-conditioning system. 2). Term that may apply to brake or power-steering hoses.

Glossary “pressure multiplier” Definition:
It usually applies welder arm pressure.

Glossary “pressure plate” Definition:
Part of a manual clutch that is mounted on and rotates with the flywheel and exerts pressure against the friction disk. Also found in A/T clutch packs, used to apply force to the fiction clutches.

Glossary “pressure plate assembly” Definition:
An assembly of various parts that operate to “press” the clutch disc against the flywheel, engaging power flow to the input shaft, or “release” the disc, disengaging power flow.

Glossary “pressure priming” Definition:
Method of priming the lubrication system with oil from a pressure tank.

Glossary “pressure gauge” Definition:
Device that reads in pounds per square inch or kilograms per square centimeter.

Glossary “pressure hold” Definition:
Condition in an ABS control module in which no more braking pressure is applied to a brake circuit, because the module senses a wheel lock-up condition.

Glossary “pressure hose” Definition:
Special reinforced high-pressure hose through which pressurized fluid flows.

Glossary “pressure differential” Definition:
The difference between two pressures or two surfaces or in two separate areas. The pressure can be either pneumatic ( air ) or hydraulic ( fluid )

Glossary “pressure differential valve” Definition:
Valve used in a dual-brake system to turn on a dash warning light if the pressure drops in either part of the system.

Glossary “pressure drop” Definition:
The loss of pressure due to a restriction, or the pressure required by a component to perform its designed task or function.