L27/38

Common issues

• Excessive cylinder liner wear and piston ring breakage due to poor lubrication, fuel quality, or extended service intervals.
• Fuel injector nozzle fouling or failure leading to poor combustion, increased exhaust temperature, and potential engine damage.
• Bearing wear (main, connecting rod, camshaft) indicated by increased lube oil consumption, metal particles in oil, or abnormal noise.
• Turbocharger fouling or bearing failure, resulting in reduced engine power, high exhaust temperatures, and black smoke.
• Corrosion in cooling water systems (jacket water, charge air cooler) leading to reduced heat transfer efficiency and potential leaks.
• Malfunctions of engine control system sensors (e.g., temperature, pressure, speed) or actuators due to vibration, moisture ingress, or aging.
• Exhaust valve burning or seat wear, causing loss of compression and reduced engine efficiency.
• Vibration-induced fatigue cracks in piping, brackets, or structural components.

Inspection checklist

• Visual inspection for fuel, lube oil, and cooling water leakages around the engine, piping, and connections.
• Check engine room cleanliness, bilge condition, and presence of oil/water emulsions.
• Verify operational parameters (temperatures, pressures, speeds) against manufacturer's specifications and logbook entries.
• Inspect turbocharger for signs of fouling, oil leaks, or abnormal noise; check air filter condition.
• Test emergency shutdown systems (local and remote) and overspeed trip device functionality.
• Examine fuel injection system for leaks, proper atomization (if possible), and condition of high-pressure pipes.
• Check condition of exhaust gas manifold and bellows for cracks, leaks, or insulation damage.
• Inspect engine mounting bolts and chocks for tightness and signs of movement.
• Verify functionality of all safety alarms and monitoring systems.
• Conduct crankcase inspection (if accessible and safe) for abnormal conditions, water presence, or bearing debris.

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Complete set of fuel injector nozzles and/or complete injectors.
• Full set of piston rings for at least one cylinder.
• Assorted O-rings, gaskets, and seals for common maintenance tasks (e.g., cylinder head, fuel pump).
• Fuel oil filters (primary and secondary) and lube oil filters.
• Main and connecting rod bearing shells (at least one set for emergency replacement).
• Engine control system sensors (e.g., speed, temperature, pressure) and relevant fuses.
• Exhaust valve and seat ring (at least one set).
• High-pressure fuel pipe for at least one cylinder.

Safety

• Risk of crankcase explosion due to overheating bearings or piston seizure, requiring functional oil mist detectors and crankcase relief valves.
• High-pressure fuel oil leaks (spray fires) from injection lines or pumps, demanding proper shielding and regular inspection.
• Hot surfaces (exhaust manifold, turbocharger) posing burn hazards; ensure insulation is intact.
• Rotating machinery (flywheel, shaft couplings) requiring robust guarding to prevent entanglement.
• Potential for overspeed due to governor malfunction or fuel system issues, necessitating a reliable overspeed trip device.

Class survey

Class surveyors will typically review engine logbooks, maintenance records, and previous survey reports. They will conduct visual inspections for general condition, cleanliness, leakages, and securing arrangements. Operational tests include emergency stop, overspeed trip, and alarm functionality. Depending on the survey cycle (e.g., special survey), they may require opening of cylinder heads, crankcase inspection, bearing clearances measurement, and verification of safety devices (e.g., pressure relief valves, flame traps). Fuel oil and lubricating oil systems integrity, cooling water system condition, and exhaust gas system integrity are also key focus areas. Bridge control and local control functionality will be checked.