What causes the fire in the scavenging spaces? How to prevent and fight such fires?
Fires in the scavenging spaces cause by
- Ignition of carbon deposits in scavenge air by means of prolonged blow by
- Slow combustion in the cylinder due to incorrect atomization
- Blow-back through scavenge air ports due to incorrectly adjusted exhaust cam disc or back pressure
Signs of Scavenge Fire
- Increased in exhaust temperature of the affected cylinder
- Turbocharger may surge
- Smoke from the turbocharger's air inlet filter
- Hotter scavenging air box casing.
Actions to be taken
- Reduce speed to slow and ask bridge for permission to step
- Stop the auxiliary blower it fitted
- Stop the fuel oil supply.
- Put the scavenging spaces fire extinguishing system into a function. 5 After extinguishing the fire, remove dry deposit and sludge from all the scavenge air boxes.
- Clean and inspect respective piston rod and cylinder liner, their surfaces alignment if affected.
Preventive actions
- Regular cleaning and inspection of scavenging spaces
- Keep fuel injectors and fuel pumps in good operational order
- Check the fuel supply and valves opening timing regularly