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Scavenge space fire

Factors:
combustible material: cylinder lube oil mixed with fuel carried to scavenge spaces,
heat source- heat in scavenge space .
oxygen- scavenge air and ignition source- blow past from piston rings.
Indications: slight reduction in engine speed intially due to the reduction in engine power. high exhaust temperatures in certain cylinders, irregular speed of t/s. smoky exhaust, discharge of soot smuts or carbon particles. very hot spots around scange trun areas,  scavange high temperature alarm,
Actions in case of scavenge fire:
 objective is first to contain and then minimise the damage to engine.
1. engine must be put to dead slow ahead and fuel must be taken off from tha affected cylinder
2. lubrication to the affected cylinder must be increased to prevent piston seizure.
3. scavenge space drains must be shut down to prevent discharge of sparks and burning oil.

If scavenge fire is major in nature use steam extinguishing media.

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