Why is a ventilation device installed in the engine crankcase?
2 Answers
Engine crankcase ventilation device is installed to extend the service life of the engine oil, reduce component wear, prevent oil leakage, recover unburned gases in the crankcase, and reduce exhaust pollution. Therefore, the crankcase needs to be ventilated, hence the installation of a ventilation device. The method of engine crankcase ventilation utilizes the vacuum effect of the engine intake pipe to draw out the gases from the crankcase and then introduces fresh air. The most widely used method is the closed forced ventilation system, which involves installing a one-way valve at the crankcase air inlet. This valve only allows outside air to enter the crankcase and prevents gases inside the crankcase from being discharged into the atmosphere, keeping the crankcase in a fully enclosed state.
Actually, I've driven quite a few cars and found that setting up a crankcase ventilation system is really crucial. I remember my old car from earlier years always leaked engine oil. The mechanic mentioned during repairs that when the engine runs, combustion gases can slip past the piston rings into the crankcase—this is called blow-by, which causes internal pressure to skyrocket. Without ventilation, the oil seals can't handle it and start leaking, and the engine oil gets contaminated into a sludge-like state, corroding components. The ventilation system sucks these gases back into the intake system to be burned again, controlling pressure while reducing emissions—how eco-friendly! This significantly extends engine life. I used to neglect maintenance and only understood after several repairs. Regular checks can prevent many car issues, saving a lot on repair costs and making daily driving much more reassuring.
