6L6EY18ALW

Common issues

• Common Rail injector nozzle wear, clogging, or leakage leading to poor combustion and high exhaust temperatures.
• High-pressure fuel pump (HPFP) element wear or control valve malfunction, impacting fuel rail pressure stability.
• Exhaust valve burning or seat wear, particularly when operating on HFO due to vanadium and sulfur content.
• Turbocharger bearing wear or fouling of compressor/turbine blades, reducing efficiency and increasing exhaust back pressure.
• Lube oil contamination or degradation, leading to accelerated bearing wear and piston ring sticking.
• Cooling water system blockages, scale formation, or leaks, causing localized overheating or reduced cooling efficiency.
• Fuel oil system filter clogging (especially HFO) due to poor fuel quality or purifier inefficiency.
• Engine Control Unit (ECU) or critical sensor (e.g., fuel rail pressure, exhaust gas temperature) malfunctions.

Inspection checklist

• Check for any visible leaks (fuel, lube oil, cooling water) around the engine, piping, and connections.
• Monitor individual cylinder exhaust gas temperatures and turbocharger inlet/outlet temperatures for abnormalities.
• Verify lube oil pressure and temperature, check oil level, and visually assess oil condition (color, presence of water/sludge).
• Inspect fuel oil filters (primary and secondary) for excessive differential pressure, indicating clogging.
• Listen for abnormal noises from the engine, injectors, turbocharger, or rotating components.
• Check common rail fuel pressure stability and observe injector return line flow for consistency.
• Inspect turbocharger for excessive axial or radial play (if accessible and safe to do so during maintenance).
• Verify cooling water system pressures and temperatures, and check the expansion tank level.
• Test critical alarms and safety shutdowns (e.g., overspeed, low lube oil pressure, high cooling water temperature).
• Inspect engine mounting bolts and vibration dampeners for looseness, cracking, or excessive wear.

Service intervals

Typical wear limits

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

Critical spares

• Common Rail Injector assembly (at least one per cylinder, or a few spares)
• High-pressure fuel pump repair kit or spare elements/control valves
• Full set of Lube Oil and Fuel Oil filters (primary and secondary)
• Turbocharger bearing cartridge or repair kit
• Critical sensors (Lube Oil pressure, Cooling Water temperature, Exhaust Gas temperature, Speed sensor)
• Exhaust valve and seat ring (especially for HFO operation)
• Various O-rings and gaskets for common maintenance tasks (e.g., cylinder head cover, fuel lines)
• Fuel pressure regulating valve (Common Rail system)

Safety

• High-Pressure Fuel System: Common Rail systems operate at extremely high pressures (1000-2000+ bar). Leaks can cause severe injury (e.g., fuel injection into skin). Always depressurize the system before any maintenance.
• Hot Surfaces & Exhaust Gases: Engine surfaces, exhaust manifold, and turbocharger are extremely hot during and after operation. Risk of severe burns. Exhaust gases are toxic and require proper ventilation.
• Rotating Machinery: Ensure all guards are in place for rotating parts (flywheel, fan, coupling). Always secure the engine against accidental start-up using proper lockout/tagout procedures before working on it.
• Electrical Hazards: High voltage from the generator and control system wiring. Follow strict electrical safety procedures and ensure power is isolated before working on electrical components.
• Fuel Handling (HFO): Hot HFO can cause severe burns. Proper Personal Protective Equipment (PPE) and spill containment procedures are essential during HFO transfer and maintenance.

Class survey

Class surveyors typically focus on: 1. Documentation Review: Thorough check of engine logbooks, maintenance records, lube oil analysis reports, spare parts certificates, and previous survey reports. 2. Operational Test: Witnessing engine start-up, stable running at various loads (if possible), and verification of critical parameters (pressures, temperatures, fuel rail pressure). 3. Safety Devices: Testing of overspeed trip, low lube oil pressure shutdown, high cooling water temperature shutdown, and other critical alarms. 4. Visual Inspection: Checking for fuel, lube oil, and cooling water leaks. Inspection of engine foundations, mounting bolts, vibration dampeners, and general cleanliness. 5. Crankshaft Deflection: May be requested if the engine has significant running hours or if there are concerns about bearing wear. 6. Fuel System Integrity: Inspection of HFO/MGO changeover arrangements, fuel lines, purifiers, and filters. Verification of proper insulation on hot HFO lines. 7. Exhaust System: Inspection of exhaust manifold, bellows, and turbocharger for leaks or damage. 8. Emergency Stop: Verification of local and remote emergency stop functions.

Estimated lifetime: 60,000 - 80,000 hours (before major crankshaft-out overhaul)