What is vacuum?

vacuum vent valve

Glossary “vacuum vent valve” Definition:
Controls the induction of fresh air into a vacuum system to prevent chemical decay of the vacuum diaphragm that can occur on contact with fuel. The valve should be mounted with ports pointed downward for fuel drainback.

vacuum suction cup

Glossary “vacuum suction cup” Definition:
Tool that uses a remote power source (separate vacuum pump or air compressor airflow) to produce a negative pressure (vacuum) in the spray gun cup. It also refers to a tool that is used pull out larger dent than can be done with just a suction cup.

vacuum regulator valve

Glossary “vacuum regulator valve” Definition:
Vacuum regulator which provides a constant output signal when the input level is greater than a preset level. At a lower input vacuum the output equals the input. Some systems use 3-port or 4-port valves to control the vacuum advance to the distributor.