FT FT-14

Common issues

• Bearing wear and failure (journal and thrust bearings) due to contaminated lube oil, insufficient oil pressure, or prolonged operation at high vibration levels.
• Compressor fouling (salt, dust, oil mist) leading to reduced air delivery, surging, increased exhaust gas temperature, and decreased engine efficiency.
• Turbine fouling (carbon deposits from unburnt fuel) causing reduced turbine efficiency, increased back pressure, and potential imbalance.
• Rotor imbalance and vibration, often caused by blade damage (erosion, foreign object impact), uneven fouling, or bearing deterioration, leading to accelerated wear.
• Exhaust gas leakage from casing joints, sealing rings, or expansion bellows, resulting in power loss and potential fire hazard.
• Oil leakage from bearing housing seals (labyrinth seals) into the compressor or turbine side, indicating seal wear or improper drainage.
• Cracks in turbine casing or nozzle ring due to thermal stress cycling, especially with frequent load changes or rapid cooling.

Inspection checklist

• Operational check for abnormal noise (whining, grinding) or excessive vibration. Use a vibration meter if available.
• Verify lubricating oil pressure and temperature at turbocharger inlet/outlet. Ensure oil flow is adequate and within specified limits.
• Inspect compressor and turbine blades for fouling, erosion, or damage through inspection ports (if fitted) or during shutdown. Note any signs of rubbing.
• Check exhaust gas and air inlet/outlet ducts for leaks (visual, soap test for air leaks, thermal imaging for exhaust leaks).
• Monitor bearing temperatures (if sensors are installed) and compare with normal operating ranges. Look for sudden spikes or sustained high temperatures.
• Inspect the condition of the air filter and silencer. Ensure no blockages or damage that could lead to foreign object ingress.
• Check axial and radial clearances of the rotor (during shutdown, as per manufacturer's procedure) to assess bearing wear.
• Examine the turbocharger casing, especially the hot parts (turbine housing), for cracks, distortion, or signs of overheating.
• Verify the proper functioning of the turbocharger drain lines from the bearing housing to the engine sump or drain tank.

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 (or individual journal and thrust bearings)
• Oil sealing rings (labyrinth seals) for compressor and turbine sides
• Gasket and O-ring set for casing joints, oil lines, and air/gas ducts
• Nozzle ring segments or complete nozzle ring (if applicable to design)
• Diffuser (if prone to damage or erosion)
• High-speed balancing kit (if major overhauls are performed onboard, though less common now)
• Lubricating oil filter elements (if specific to turbocharger system)

Safety

• Hot surfaces: The turbine casing and exhaust gas piping operate at extremely high temperatures. Risk of severe burns. Ensure proper lagging and warning signs.
• High-speed rotating parts: The rotor operates at tens of thousands of RPM. Risk of severe injury if opened or accessed while running. Always ensure engine shutdown and rotor stopped before any inspection or maintenance.
• Potential for rotor burst: While rare, catastrophic failure of the rotor due to extreme imbalance or material fatigue can release high-velocity fragments. Regular maintenance and adherence to wear limits are crucial.
• Pressurized systems: Air and exhaust gas ducts can be under pressure. Ensure depressurization before opening any covers or connections.
• Asbestos-containing materials: Older units may contain asbestos in gaskets or insulation. Always verify material safety data sheets and use appropriate PPE if handling such materials.

Class survey

A class surveyor will typically verify the following: 1. Review of maintenance records, logbook entries, and service reports for compliance with planned maintenance system. 2. Visual inspection for any oil, air, or exhaust gas leaks from the turbocharger and its associated piping. 3. Assessment of turbocharger operational parameters (bearing temperatures, lube oil pressure, exhaust gas temperatures) against normal values. 4. Check for abnormal noise or vibration during engine operation. 5. Inspection of safety devices, such as overspeed trip mechanisms and alarm settings. 6. Verification of casing integrity, insulation, and lagging condition. 7. If opened for overhaul, inspection of rotor, bearings, nozzle ring, and diffuser for wear and damage. 8. Confirmation of compliance with relevant SOLAS and MARPOL regulations, especially regarding exhaust gas temperature monitoring and emissions control if applicable.

Estimated lifetime: 16,000 to 24,000 hours before major overhaul/replacement of critical components, depending heavily on operating conditions, fuel quality, and maintenance regime. Some units can exceed 30,000 hours with diligent care.