Scavenge Fire
Fire in the scavenge air space of a two-stroke crosshead engine, ignited by leaking fuel + carbon deposits + scavenge air.
In practice
Detected by the oil-mist detector and rising scavenge-receiver temperature. The OOW reduces engine load to dead slow, isolates affected cylinder, and starts cylinder-oil flush. Late detection causes piston-rod corrosion and crankcase contamination.
Regulatory detail & full definition
Symptoms: rising scavenge-air temperature on one cylinder, surging exhaust temperature, possibly reduced engine speed. Procedure: slow down, stop fuel to the affected cylinder, open scavenge fire-extinguishing connection (steam smothering), monitor temperature. Major fires can warp the cylinder liner. Prevented by good piston-ring seating and routine scavenge-space inspection.
Related
Source: Industry usage; MAN B&W Operating Manual safety guidance
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