Engineering · Diesel — Safety
A crankcase explosion in a large diesel is most likely caused by:
- ALow cooling-water temperature
- BAn oil mist ignited by a hot spot such as an overheated bearing✓ Correct
- CExcess scavenge air pressure
- DHigh fuel cetane number
Explanation
A hot spot (e.g., a running bearing) vaporizes lube oil into a flammable mist; ignition causes a primary explosion. This is why crankcase oil-mist detectors and relief doors are fitted.
Authority: Diesel Engines (USCG engineering topic)
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