A100-H 100-H47

Common issues

• Bearing wear (journal and thrust bearings) leading to increased axial/radial play and vibration.
• Compressor wheel fouling due to intake air contamination or oil carry-over, reducing efficiency and air flow.
• Turbine wheel and nozzle ring fouling/erosion from poor combustion, high exhaust gas temperatures, or abrasive particles.
• Oil leakage from bearing housing (compressor or turbine side) indicating seal ring wear or damage.
• Rotor imbalance causing excessive vibration, often due to blade damage, fouling, or bearing issues.
• Cracks in turbine casing or exhaust gas manifold connections due to thermal stress and fatigue.
• Foreign object damage (FOD) to compressor or turbine blades, leading to imbalance and potential catastrophic failure.
• Degradation of charge air cooler efficiency, indirectly impacting turbocharger performance by increasing back pressure.

Inspection checklist

• Visually inspect for any oil leaks around the bearing casing, oil inlet/outlet pipes, and air/gas connections.
• Check for abnormal noise (whining, grinding) or excessive vibration during operation. Use a vibration meter if available.
• Inspect compressor wheel through the intake for fouling, erosion, or blade damage. Check for rubbing marks on the casing.
• Inspect turbine wheel and nozzle ring (via inspection port, if fitted) for fouling, erosion, cracks, or foreign object damage.
• Verify charge air pressure and exhaust gas temperature readings against engine load and manufacturer's specifications.
• Check the condition of the air filter elements; a clogged filter restricts airflow and can cause compressor surging.
• During planned maintenance, measure axial and radial bearing clearances and compare against wear limits.
• Inspect all mounting bolts and connections for tightness and signs of thermal stress or corrosion.
• Check the condition of the cooling water system (if water-cooled) for leaks, proper flow, and temperature.

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 bearing cartridge assembly (journal bearings, thrust bearings, and associated seals)
• Set of labyrinth seal rings (compressor and turbine side)
• O-rings and gaskets for casing, oil, and water connections
• Nozzle ring (if replaceable separately and subject to wear)
• Mounting bolts and nuts (especially for hot sections)
• Oil filter elements (if integrated into the turbocharger's lubrication system)
• Cleaning agents for compressor and turbine washing
• Emergency repair kit for minor leaks (e.g., high-temperature sealant, clamps)

Safety

• High surface temperatures (exhaust casing, turbine housing) posing severe burn risks. Always use appropriate PPE.
• High rotational speeds of the rotor assembly (up to 100,000+ RPM). Catastrophic failure can release high-energy fragments.
• Pressurized air and exhaust gas lines. Ensure systems are depressurized before opening any connections.
• Hot lubricating oil under pressure. Risk of burns and fire if leaks occur.
• High noise levels during operation require hearing protection in the vicinity of the turbocharger.

Class survey

Class surveyors typically verify the turbocharger's maintenance history, including dates of minor and major overhauls, and records of bearing replacements. They will conduct a visual inspection for external oil leaks, cracks on casings, and general cleanliness. Operational checks may include monitoring charge air pressure, exhaust gas temperatures, and listening for abnormal noises. The availability of critical spare parts onboard, particularly bearing cartridges and seal rings, is also a key check. They will ensure that the turbocharger's performance is within acceptable limits for the engine's safe operation and that any safety devices (e.g., overspeed protection, if fitted) are in good order.

Estimated lifetime: 16,000-24,000 hours before major overhaul (replacement of all wear parts, rebalancing of rotor)