Do horizontally opposed engines burn oil?
2 Answers
Horizontally opposed engines may experience oil burning after accumulating high mileage. In this type of engine, the cylinders are horizontally arranged and the pistons move horizontally. Due to gravity's effect on the horizontally opposed pistons, the lower cylinder walls tend to wear more severely, leading to uneven wear issues in some horizontally opposed engines. When cylinder wall wear becomes significant, it can result in oil burning. Oil burning refers to engine oil entering the combustion chamber and burning along with the fuel. When a car starts burning oil, symptoms may include increased carbon deposits, unstable idle, weak acceleration, and higher fuel consumption. If oil burning occurs, it's essential to have the vehicle inspected by professionals at a repair shop or 4S dealership to prevent potential engine damage.
I have quite a bit of experience with horizontally opposed engines, like those in Subarus. Because the cylinders are arranged parallel to the ground, gravity tends to make oil accumulate at the bottom. Over time, if the piston rings wear out or don't seal properly, it increases the risk of oil burning. My old car often had this issue, requiring regular top-ups. But this isn't the case for all cars; newer models have seen significant improvements. Choosing the right synthetic oil viscosity (such as 5W-30) and checking oil levels every 5,000 km can greatly mitigate the problem. A slight oil burn is normal, but blue smoke is dangerous—it affects performance and shortens engine life. Overall, horizontally opposed engines have many advantages, like stable handling, as long as maintenance is kept up. The key is not to ignore small issues; catching them early saves money and ensures safety.
