What Causes Diesel Engine Exhaust Pipe to Spray Engine Oil?
2 Answers
The reasons for a diesel engine exhaust pipe spraying engine oil: 1. Natural wear of the power system, excessive clearance between the piston rings and cylinder liner; 2. Excessive engine oil leading to high pressure in the engine compartment; 3. Failure of the piston pin and cylinder liner; 4. Severe wear or poor sealing between the valve stem and valve guide. A diesel engine is an engine that burns diesel to obtain energy release. Its working process shares many similarities with a gasoline engine, with each working cycle also going through four strokes: intake, compression, power, and exhaust. Diesel engines use compressed air to increase air temperature, making it exceed the auto-ignition point of diesel. At this point, diesel is injected, atomized, and mixes with air while igniting and burning on its own.
When I'm doing long-haul transportation, I often use diesel trucks. It's quite common to see oil spraying from the exhaust pipe, mostly caused by worn piston rings allowing oil to sneak into the combustion chamber and burn, resulting in blue smoke. Oil leaks up from the crankcase due to reasons like poor driving habits and infrequent maintenance, such as prolonged high-load operation wearing out components. This is also accompanied by increased fuel consumption and reduced power, and over time the engine may fail prematurely. My experience is that once you notice blue smoke or oil traces, immediately stop to check the dipstick level, and replace the piston rings and seal kit if necessary, otherwise the risk of breaking down on the road is high. Regular oil changes and using high-quality filters in daily maintenance can reduce such issues. Early repairs aren't costly, but delaying them can make the repair bill half the price of a new truck.
