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Description & Operation

Blow-by gases leave crankcase through a cast riser bore and then enter ventilation dome in the oil filler neck. The ventilation dome acts as an oil trap for gases. From the trap, gases are routed to engine intake through a flow valve and connecting hoses for combustion.

Any trapped fresh oil passes through a drain tube and into the oil pan. The flow valve prevents blockage due to freezing by very low ambient temperature.

Fig 1: Crankcase Ventilation System
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