If the crankcase ventilation system is clogged with dirt, the engine literally begins to “blow”. Gases break the drive unit and try to escape through the dipstick, oil filler neck, or through various seals and seals. If the crankshaft oil seal is squeezed out in this manner, oil will begin to splatter through this “hole” causing serious problems. As for the probe, it can also be squeezed out.
If we talk about the designs of ventilation systems, then many have been invented. It can be a conventional venting system or a complex PCV (Positive Crankcase Ventilation) system, ie a forced ventilation system. It can have two circuits, a pressure reducing valve and a pump. In short, before buying a used car, it would be nice to study this nuance to know where to look.
Since the valve breaks most often, you need to know how to check its performance quickly. It is easiest to unscrew the oil filler cap while the engine is running. Then we put our hand on it. If you feel the pressure of outgoing vapors, the valve is not working. But there is a nuance. There will still be some pressure on the BMW N42 and N46 engines, so in the case of the “Germans” this method does not help much.
There is also an opinion that in a serviceable engine the cover sticks to the neck. This is true, but not always. If it sucks too hard, the valve could get stuck in the open position or the diaphragm ruptured.
There are more radical ways to check. It is necessary to disassemble and shake the valve. If nothing rattles, it’s stuck. However, it is best to remove the ventilation pipes yourself, as this is not difficult, and inspect their “inside”. If dirt and deposits are visible then most likely the valve is also clogged and not working. In this case, this is an armed concrete argument to demand a discount from the seller. And ideally you should measure the compression after cleaning and rinsing. If it does not correspond to the norm, there is slag in the system, and such an engine will soon “die”.
If the crankcase ventilation system is clogged with dirt, the engine literally begins to “blow”. Gases break the drive unit and try to escape through the dipstick, oil filler neck, or through various seals and seals. If the crankshaft seal is squeezed in this way, oil will begin to splatter through this “hole” causing serious problems. As for the probe, it can also be squeezed out.
If we talk about the designs of ventilation systems, then many have been invented. It can be a conventional venting system or a complex PCV (Positive Crankcase Ventilation) system, ie a forced ventilation system. It can have two circuits, a pressure reducing valve and a pump. In short, before buying a used car, it would be nice to study this nuance to know where to look.
Since the valve breaks most often, you need to know how to check its performance quickly. It is easiest to unscrew the oil filler cap while the engine is running. Then we put our hand on it. If you feel the pressure of outgoing vapors, the valve is not working. But there is a nuance. There will still be some pressure on the BMW N42 and N46 engines, so in the case of the “Germans” this method does not help much.
There is also an opinion that in a serviceable engine the cover sticks to the neck. This is true, but not always. If it sucks too hard, the valve could get stuck in the open position or the diaphragm ruptured.
There are more radical ways to check. It is necessary to disassemble and shake the valve. If nothing rattles, it’s stuck. However, it is best to remove the ventilation pipes yourself, as this is not difficult, and inspect their “inside”. If dirt and deposits are visible then most likely the valve is also clogged and not working. In this case, this is an armed concrete argument to demand a discount from the seller. And ideally you should measure the compression after cleaning and rinsing. If it does not meet the standard, there is slag in the system, and such an engine will soon “die”.
Source: Avto Vzglyad
I’m Sandra Torres, a passionate journalist and content creator. My specialty lies in covering the latest gadgets, trends and tech news for Div Bracket. With over 5 years of experience as a professional writer, I have built up an impressive portfolio of published works that showcase my expertise in this field.