MDE Unit 11 Q7

Onboard assessment of lubricating oil condition in a large medium-speed diesel engine is crucial for maintaining engine health and preventing costly breakdowns. Here are the primary methods:

Visual Inspection

• Oil level: Check if the oil level is within the specified range.
• Oil color: Observe the oil’s color for any unusual changes (e.g., darkening, milky appearance).
• Oil consistency: Check for abnormal thickness or thinness.
• Foam or bubbles: Excessive foaming or bubbles can indicate aeration or water contamination.
• Metal particles: Inspect the oil for visible metal particles, which may indicate excessive wear.

Oil Sampling and Analysis

• Regular sampling: Collect oil samples from various points in the lubrication system for analysis.
• Laboratory analysis: Send samples to a shore-based laboratory for detailed analysis.
• Onboard testing: While less comprehensive, some onboard tests can provide preliminary indications:
  • Viscosity: Check the oil’s viscosity using a viscometer.
  • Water content: Use a water-finding paste to detect water contamination.
  • Sediment and water: Centrifuge a sample to separate sediment and water.

Monitoring Engine Parameters

• Oil pressure: Monitor oil pressure to ensure adequate lubrication.
• Oil temperature: Check oil temperature to avoid overheating.
• Engine performance: Observe engine performance for any indications of oil-related issues (e.g., increased noise, vibration, smoke).

Additional Checks

• Filter condition: Inspect the oil filter for signs of contamination or blockage.
• Oil purifier performance: Monitor the performance of the oil purifier and its discharge.
• Sensor data: Utilize engine sensors and monitoring systems to gather data on oil-related parameters.

By combining these methods, engineers can effectively assess the condition of the lubricating oil and take corrective actions as needed to prevent engine damage.