What Causes Oil Leakage at the Exhaust Manifold Interface?
2 Answers
Engine oil leakage at the exhaust manifold interface can be attributed to the following reasons: Reason 1: Prolonged engine idling; clogged or deformed crankcase ventilation system. Reason 2: Blockage, leakage, or deformation of the turbocharger's oil inlet and return pipes; coking of lubricating oil in the turbocharger's intermediate housing. Reason 3: Cylinder wear leading to piston ring blow-by; excessive flow resistance in the exhaust system. Reason 4: Poor sealing of exhaust valves or aging of oil seals. Reason 5: Engine oil burning. If the car exhibits severe oil burning, it is necessary to check the engine oil dipstick to see if the oil level has decreased. A lower oil level indicates engine oil burning.
My car has been running for over a decade, and I've encountered oil leakage at the exhaust manifold interface a few times. The main reason is the aging of the sealing gasket. Those gaskets can't withstand high temperatures and vibrations, and once they wear out, oil starts leaking. Another common issue is loose screws, which weren't tightened properly during assembly, leading to gaps and oil seepage. It could also be due to cracks or deformation in the cylinder head, allowing oil to escape from there. When I notice this problem, I usually check the gasket first. Replacing it costs around a hundred bucks. If not fixed in time, it can easily cause a fire, especially on highways where exhaust temperatures are high. For regular maintenance, I recommend periodically checking the tightness of the exhaust system screws and taking a quick look at the gasket condition during oil changes to prevent major issues.
