{"id":38405,"date":"2024-02-27T10:00:00","date_gmt":"2024-02-27T09:00:00","guid":{"rendered":"https:\/\/hifi-filter.com\/comprendre-le-systeme-de-ventilation-du-carter-moteur\/"},"modified":"2024-02-27T10:39:19","modified_gmt":"2024-02-27T09:39:19","slug":"understanding-the-crankcase-ventilation-system","status":"publish","type":"post","link":"https:\/\/hifi-filter.com\/en\/understanding-the-crankcase-ventilation-system\/","title":{"rendered":"Understanding the crankcase ventilation system"},"content":{"rendered":"
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On your vehicles, the crankcase ventilation system is essential for preserving the engine and its lubrication system.<\/strong> Why is this? By regulating the pressure in the crankcase, it prevents excessive engine wear and oil leaks, ensuring optimum performance. In the face of today’s environmental challenges, the importance of this system cannot be underestimated. It captures noxious gases charged with oil mist, preserving our atmosphere and our health. What’s more, by reinjecting the collected oil into the lubrication system, it reduces engine oil consumption. To fully understand this system, let’s go back to basics: the four-stroke engine. <\/div>\r\n<\/div>\r\n\r\n\n\n
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A closer look at how the combustion engine works<\/h2>
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A 4-stroke engine operates in four distinct phases: 1. intake, 2. compression, 3. expansion and 4. exhaust.<\/div>\n <\/div>\n<\/div>\n\n
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During intake, the piston creates a vacuum in the cylinder, allowing air to enter via an intake valve. During compression, the piston moves upwards, compressing the air while an injector introduces fuel. The resulting explosion of the air-fuel mixture pushes the piston down, generating a rotary motion that is transmitted to the vehicle’s wheels. When in operation, the burnt gases are expelled via a valve and discharged through the exhaust system.\r\nAt the same time, the lubrication system reduces friction between parts by lubricating them with engine oil, stored in the crankcase.\r\n\r\n\u26a0\ufe0fDuring engine operation, various phenomena occur in the oil sump, in particular the formation of blow-by and oil vapours, which can cause engine malfunctions.<\/strong> <\/div>\r\n<\/div>\r\n\r\n\n\n
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Blow-by: definition, origin and composition<\/h2>
In an engine, blow-by is a leak of combustion gases from the cylinders into the oil sump.<\/strong> This leak is the result of a poor seal between the piston and the cylinder, mainly due to ring wear. Over time, the friction between pistons and cylinders wears down the rings, making them less effective at retaining combustion gases.\r\n\r\nMade up of combustion gases, blow-by is a threat to the engine and the environment. It contains pollutants such as unburnt fuel, nitrogen oxides, carbon oxides, water vapour, sulphur oxide and particles from component wear.<\/div>\r\n <\/div>\r\n
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Oil mist in the crankcase<\/h2>
When the engine is running, the oil is heated to high temperatures, causing it to evaporate and form an oil mist inside the crankcase.<\/strong> Mixed with blow-by, this new vapour-gas mixture poses a threat to the engine.<\/div>\r\n <\/div>\r\n
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What are the risks for the engine?<\/h2>
The main risks associated with the combustion gas-oil vapour mixture are :\r\n