Exhaust Emissions System - Crankcase Ventilation: Description: 928

Blow-by gases are routed from the crankcase to an oil separator where any excess oil in the gases can settle and flow back to the pan. From oil separator, the blow-by gases continue to the lower section of the air cleaner. A preheating line runs across part of the vent hose. This helps keep the blow-by gases at a temperature which is more suitable for combustion once they are taken into the combustion chamber. A flame guard is also installed in the inlet adapter of the air cleaner (lower portion) to prevent backfire flame from reaching the crankcase.