Good sealing rings are essential to the health, well-being, and longevity of your engine and that’s true whether we’re talking about a full tilt race engine or the little buzzing mill in the front of your daily commuter. In this video, pal o’ BangShift and Mahle Training Team Leader Bill McKnight explains the basic differences between the ring packages regularly found in passenger car gasoline engines and those found in diesel engines. Between variations in the way that the fuels work and burn, the vastly different compression ratios that the engines see, and the wide gulf in longevity expectations there are some interesting things that separate the two.
Obviously big diesel engines in trucks are designed to go 500,000-1,000,000 miles before being torn apart and rebuilt. Yes, passenger cars can do that but most will not, so right off the bat there are cost and other concerns with those expectations. There’s obviously material concerns and other factors that go into deciding what the rings will be made of, how they will be shaped, and how many lands are used. That’s actually one of the things that most gas and diesel engines share and that is the fact that typically they are both three ring designs with a top ring, a middle oil control ring, and a final “scraper” ring that does the work on the bottom.
The hows and whys that companies like Mahle understand and execute are interesting to learn about. Rings need to seal but no provide too much friction, they need to wear but not before the rest of the components, and they have to work in what is pretty much the harshest place in the engine. Not easy stuff! This video does a great deal to shed some light onto diesel rings and what makes them tick.
