Which of the following statements is true about "blowby"?

The statement that properly installed piston rings prevent blowby is accurate. Blowby refers to the phenomenon where combustion gases escape past the piston rings and enter the crankcase during the combustion process. This typically occurs when the piston rings are not making effective contact with the cylinder walls or are otherwise damaged, allowing gases to seep through. When the piston rings are installed correctly and in good condition, they create a tight seal against the cylinder walls, effectively containing the combustion gases within the combustion chamber. This sealing action is crucial for maintaining optimal engine performance, fuel efficiency, and reducing emissions.

The effectiveness of the piston rings in preventing blowby is an important aspect of engine design and function, as excessive blowby can lead to a variety of issues, including decreased engine power, increased oil contamination, and increased wear on engine components. Hence, having properly installed piston rings is essential for the overall health and efficiency of the engine.