450 Models
The system consists of a fresh air hose from air cleaner to right cylinder head cover, a breather hose from left cylinder head cover, a 2 mm orifice, and a connection in the idle air distributor.
During idle or low speed operation, vapors are drawn through the orifice, into the idle air distributor tubes, then into the intake manifold. Fresh air to vent the engine comes through the air cleaner and right cylinder head cover hose. During high speed operation, vapors pass through hose into air cleaner and are drawn in to be burned. The idle air distributor is heated by engine coolant to prevent vapors from freezing in cold weather.