Engine blow-by is a result of exhaust valves in an engine not sealing correctly and some of the high-pressure air/fuel mixture leaking past them, leading to the gases from the engine’s crankcase or oil pan seeping out. The gas goes through your car’s ventilation system and then into the cabin, which is not only unsafe for your health but also can cause unpleasant smells and noise that affects performance.
This can be caused by inadequate compression seal between piston rings and cylinder walls due to improper assembly or too much carbon buildup on those surfaces. As you might imagine, this affects everything from performance to fuel economy. Gasoline fumes may have profound health implications such as respiratory problems like asthma or chronic obstructive pulmonary disorder (COPD).
Fortunately, there are ways to prevent it!
How does Engine Blow-By happen?
The inner workings of engines can be complex, and a lot of gas gets released into the engine as it runs. These gases affect the integrity of the engine if left unchecked. As a result, the engine needs regular maintenance with an oil change every 10-20 thousand miles.
The biggest misconception about cars is that all exhaust comes out through the tailpipe. This misconception can lead to engine blow-by – a situation that happens when the pressure in an engine’s combustion chamber exceeds atmospheric pressure and forces excess air into oil passages or coolant lines. This often results in costly repairs like broken head gaskets or blown turbochargers because it increases wear on critical components.
Typically, engine blow-by may occur when the seals of an engine are not functioning as they should. Sometimes, it might happen when the cylinder walls are not perfect, resulting in some degree of leakage between cylinders through which air can move around inside your car. When this happens, it usually results in noisy operation at lower speeds or even more severe misfiring issues.
Engine blow-by gas contains unburned fuel and other harmful emissions such as nitrogen dioxide (NO2), carbon monoxide (CO), and hydrocarbons (HC). These gases are detrimental to the environment and are toxic to humans.
Keep in mind that these gases smell terrible, so be aware of any funny smells while driving. It could be an indicator of something more serious.
Besides, the leaked air can contaminate oil seals if it is allowed into an automotive transmission system. This could lead to catastrophic mechanical failure in your vehicle. Blow-by leads typically to a growling engine – more or less like a sports car. If your car is not tuned to produce such sounds, consult the mechanic.
Also, it can cause an oil leak, corrosion to metal surfaces, and make it difficult for your car to maintain adequate levels of compression, resulting in reduced fuel economy or power production.
Preventing Engine Blow-By
Undoubtedly, engine blow-by can cause serious damages to your car. It is vital to be vigilant – regularly check your vehicle for leakages to avoid more issues.
Regular maintenance can help minimise the effects of blow-by by keeping an airtight seal between two parts. The first and most crucial thing to do is change the coolant or the engine oil after every 10 thousand miles on average.
During the winter months, consider top-ups on the antifreeze solution. Above all, you should select high-quality oils, lubricants, and antifreeze.