190E 2.3-16
The system consists of an oil separator located in the valve cover, idle speed air distributor, idle speed air line, coolant lines and connecting hoses.
When the engine is operating under high intake manifold vacuum, blow-by gases flow out of the valve cover, through the by-pass bore in the idle speed air distributor, and into the intake manifold idle speed air passage. A small amount of filtered air is drawn into system through the by-pass hole.
When the engine is operating at low or no intake manifold vacuum, blow-by gases flow into the air cleaner where they are mixed with filtered air before burning.
To ensure against vent line freezing, coolant is routed to vent line from cylinder head. Coolant returns to water pump through coolant return line. See Fig 1 .