M/E Scavenge space inspections

Technical Management Main Engine
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The inspection of the M/E condition through scavenge ports should be carried out frequently. The early detection of wear mechanisms (corrosive, abrasive and adhesive wear) and the determination of the root cause will prevent costly and catastrophic damages that may put the safety of the vessel at stake.

Equipment to be used during the inspection:

  • Feeler Gauge
  • Flashlight
  • Vernier Gauge for CL grooves measurement
  • Small Camera able to fit inside liner scavenge ports
    -Pencil, marker/chalk
    -Mallet with preferably wooden handle or bronze bar
    -Screwdriver for non-return flaps of air intake
    -Mirror with telescopic handle
    -Clean Rags

A recommended procedure is the following:

  • Carry out the inspection with the scavenge space “dirty” before cleaning and with the main lube oil pumps running.
  • Measure the clearance of piston rings from grooves using a feeler gauge and compare with makers measurements
  • Measure the CL grooves using a Vernier gauge (where accessible) and compare with maker values).
  • Use a mallet or bronze bar to check the piston ring movements.
  • Use a screwdriver to check the non-return valves.
  • Evaluate the carbon deposits on the piston crown top and ring lands.
  • Evaluate the condition of the piston ring running surfaces visually and check for signs of seizures, cracks, missing/broken parts, over or under lubrication. It is recommended to clean one scavenge port by a rag and leave the other ports in their current condition (lubricated). In this way you can evaluate the under or over lubrication. Take close-up photos.
  • Measure the cermet coating thickness on the piston ring surface (where applicable) using an elcometer. The piston ring surface has to be cleaned before the elcometer measurements. Compare the cermet coating measurements with the maker values.
  • Check for traces of water, fuel or lube oil leakages on the piston crown top.
    -Check the condition of the piston skirt and for system oil leakages from the piston crown studs.
  • When the piston is at the bottom dead center check the condition of the cylinder liner surface (wave cut marks, seizures, polishing, corrosion).

Use the forms provided in the manual for reporting and always add in your report a representative set of clear photos for each unit. Upon completion, it is recommended to clean the M/E scavenge space and unclog the scavenge drain pipes.

I am attaching a photographic guidance for accurate reporting.

ME Scavenge space inpsection report.pdf (743.9 KB)

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