Continuation of Part I...
And here begins the most interesting, namely the device of the recirculation of crankcase gases, they can be separated from relatively "old" to the progressive "new".
The old device. Everything was just "like a drum", from the crankcase release of a special "tube" (hose) sometimes it was even just a box on the block, which is simply connected with the atmosphere, Yes, they just went into the atmosphere. Then all was absolutely "on the side" on the environment, the vehicles do not have any systems ecology (such as catalysts , etc.). Stood a special "catcher" (sometimes just a maze of small channels, sometimes metal mesh), which delayed oil mist and returns it in the form of oil back into the engine.
It should be noted on the contamination of crankcase gases – in fact it is the unburned air / fuel mixture + "testing", which escaped directly from the combustion chamber, mixed with the "oil mist" which is in the crankcase of internal combustion engines. And all this rattling (very dirty) mixture before (without filter) were just in the hood space, and then the atmosphere. By the way, the driver and passengers all this, too, could breathe, because nothing prevented those gases to pass into the cabin
The first recirculation system. BUT then people started thinking it is not right and need this thing (at least minimally) filter. Therefore, the first carburetor, for example, VAZ 2101 – 2103, the blow-by gases raised the hose up and out to the air filter of the carburetor. The drivers of that era, I remember a round air filter that prevented dust and dirt in the carb, it was all going in a round metal case and closed the lid.
Thus, the blow-by gases, the first was not released in the atmosphere, and back sucks the engine and re-burned. This system of recycling, do not bear any practical or useful sense to the internal combustion engine, made just for the sake of the environment.
Injection of recirculation of the first generation. This is a little different because the system itself is very different from gasoline. Here of the valve cover (or engine) came out of a special nozzle (the sopun), followed by oil separator was installed (usually inside), joined the hose with one hand, which is before the throttle on the other hand crashed into the air supply line (for example, on our VAZ 2110, 2111, 2112, etc.)
In fact all the same, these gases sucks along with the new air drawn into the engine.
The only problem was that the throttle valve is relatively quickly become dirty because this gas mixture carries a little oil mist, so every 50 to 60,000 km it was desirable to clean.
Modern recycling system. Now more advanced, here's the blow-by gases up through special channels, from either the head unit or from the engine block. And through a special valve (e.g. valve recirculation), go to the intake manifold, or flow channel of air. But now the supply is almost always after the throttle
What is the EGR valve blow-by gas?
He appeared only on modern systems, and it is really useful invention.