What Is Blow-by On A Diesel Engine And Its Causes?

Diesel car owners frequently struggle with the serious build-up of carbon deposits and engine contamination from time to time. The reason why the engine of your vehicle behaves in such a manner is the blow-by on a diesel engine. Now you must be wondering what is blow-by on a diesel engine, right? Well, it is not an ordinary problem, but a drastic one that can straightaway diminish the performance of the vehicle’s engine. Certain causes are responsible for this behavior of your car engine.

So, let’s understand why diesel engine acts that way and what does blow-by gas mean:

What Is Blow-by On A Diesel Engine? Causes And Solutions

A serious issue affects the working of an engine when cylinder wall and a piston have a flawed seal, allowing the air-fuel mixture to leak into the engine’s crankcase. This is what we call as blow-by gas in a diesel engine. The possible causes of this could be low performance, lesser torque and power, and even more oil consumption. It is always advised to go for some effective maintenance tips by experts for more understanding. Now, let’s see what causes it and how does it affect the vehicle.

1.Worn Pistons

One of the reasons that can solve the answer to your question what is blow-by on a diesel engine and what causes it is the worn pistons. Unlike the cylinder walls that magnifies on wear and tear, pistons tend to become smaller. Aluminum being soft metal easily allows accumulation in the combustion chamber and creates grooves in the piston. And, this means fuel-air mixture will accumulate in the crankcase.

WHAT IS BLOW-BY ON A DIESEL ENGINE
Over time of use, worn pistons cause blow-by in engine (Photo Source: fragxpo)

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2. Damaged Cylinder Walls

Another possible reason that can lead to blow-by on a diesel engine is the damaged cylinder walls. With the continuous usage, the vehicle and its components are depleted. This includes cylinder walls as well. The continuous piston and scraping of the piston ring lead to damaged cylinder walls. This creates a gap in the cylinder, making it bigger, which further leads to easy passage of the compressed gases into the piston. We hope that these points help you to understand what is diesel blow-by easier. Worn out cylinders can never perform the way it should. So, it is always recommended to keep an eye on the cylinder.

3. Smashed Piston Rings

The third reason could be those smashes piston rings. When looking for an answer for ‘what does blow by mean on a diesel,’ this is an important point to mention. Smashed or damaged piston rings can lead to blow-by on a diesel engine. Relentless grinding of rings back and forth in the cylinder damages it, eventually. One can expect the sealing abilities of the piston ring to fail drastically with time. This certainly leads to gases easily sneaking around the back of the ring, thus simply leads to blow-by on a diesel engine.

WHAT IS BLOW-BY ON A DIESEL ENGINE
Smashed pistol rings are the culprits of blow-by (Photo Source: innovationanddiscoveries)

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The Crux

We believe that you might have got an answer to what is blow-by on a diesel engine and what causes it. So, it is recommended to keep an eye on the piston, piston rings, and even the cylinder to ensure that your vehicle is functioning properly.

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