How Are Crankcase Pressure And Blowby Related?

The engine is the beating heart of your truck, and significant engine problems can lead to costly repairs, downtime, and lost profits. Unfortunately, many issues may seem relatively minor at first, but they can quickly progress into critical failures. If you own and operate your own truck, it's crucial to recognize these problems before they lead to long-term damage.

High crankcase pressure is one situation that can lead to such problems. Increased pressure inside your engine's crankcase can push oil into areas where it doesn't belong, leading to oil consumption. Avoiding problems with your truck means recognizing why this situation occurs, how you can recognize the symptoms, and what you can do to prevent it.

Understanding Crankcase Pressure and Blowby

Blowby is a common condition where combustion fuel (diesel and oxygen) creates enough pressure to slip by the piston rings in your engine's cylinders. This situation can create increased crankcase pressure, resulting in oil consumption. Some amount of blowby occurs in any engine during the warm-up process, but this should mostly disappear as your truck reaches its optimal operating temperature.

Modern diesel engines include crankcase pressure sensors that can measure and compensate for changes in pressure, keeping your engine running smoothly. These sensors will also alert you to excessive crankcase pressures with a check engine light. This warning can often indicate a problem with blowby in your truck's engine.

Recognizing the Symptoms of Excessive Blowby

If you don't have a check engine light illuminated in your truck, you can still recognize some of the symptoms of increased crankcase pressure or excessive blowby. Early symptoms typically include oil losses without any visible leaks. As the oil leaks past the piston rings, it burns off and seemingly vanishes without a trace. You may also notice an increase in black smoke from your exhaust stack.

Oil consumption is generally a problem, regardless of why it occurs. If your truck is burning oil, you can expect increased soot deposits to form in the crankcase and inside the cylinders. This particulate matter can cause numerous problems, including wearing out the piston rings, leading to more blowby, further pressure increases, and more engine wear.

Dealing With Engine Blowby Issues

Always treat any significant engine consumption on your truck as a red flag. Running a truck with excessive crankcase pressure, oil consumption, or blowby issues can lead to costly internal damage. Although older engines will burn more oil as internal parts wear down, you should still schedule a visit with a diesel mechanic if you notice any substantial change in your oil usage.

For more information, reach out to a local diesel repair service, such as Elite Automotive.