Description & Operation: 928S
During idle and low speeds, crankcase gases travel from the oil trap, (at base of oil filler neck), through connecting hose to cylinder valve cover between cylinders No.1 and 2. Gases pass through another oil trap (inside valve cover), into a restrictor (inside elbow on valve cover), through connecting hose to the intake air distributor.
A safety valve, installed in oil filler neck, opens at pressure of 80 to 100 mbar to guide the crankcase gas direct to the air guide housing.
At high speeds, crankcase gases pass through a restrictor (at top of oil filler neck), to mix with fuel tank gases through a connecting hose into the intake air distributor.