What is crank case ventilation?

Crankcase ventilation is a system in internal combustion engines that allows for the removal of gases that accumulate in the crankcase during operation. These gases, primarily consisting of blow-by gases from the combustion process, can contain harmful pollutants and moisture. The ventilation system typically uses a PCV (Positive Crankcase Ventilation) valve to redirect these gases back into the intake manifold for re-combustion, which helps reduce emissions and maintain engine efficiency. Proper crankcase ventilation is essential for engine longevity and performance.