FixVault

Crankcase Ventilation Systems: Operation

Air enters system through a vented oil filler cap into engine crankcase where fumes are picked up and carried through ventilator valve and into intake manifold.

Ventilator valve regulates flow of fumes to intake manifold depending on intake manifold vacuum. Upon reaching intake manifold, fumes are mixed with the fuel mixture and burned in combustion chambers.

Fig 1: 1964-65 "OPEN" VENTILATION 6 CYL. 1-BBL. CARB.
G09340547Courtesy of GENERAL MOTORS COMPANY
Fig 2: TAKE-APART TYPE VENTILATION VALVE
G09340548Courtesy of GENERAL MOTORS COMPANY
Fig 3: 1963-67 "OPEN" CRANKCASE VENTILATION THREE 2-BBL. CARBS.
G09340549Courtesy of GENERAL MOTORS COMPANY