🔍 Key Concepts

• Relationship between engine load and cylinder lubrication rate on large low-speed diesels • Difference between steady sea speed operation and maneuvering (frequent RPM/load changes) • Why over-lubrication and under-lubrication are both harmful

💭 Think About

• Think about what happens to cylinder temperature and pressure when the engine is running at very low load versus normal sea speed. How would that affect the need for lubricating oil? • When the engine is running at a constant RPM and load for long periods, does the lube oil rate usually need continuous frequent adjustment, or is it set and monitored? • During maneuvering, is the engine generally under higher or lower average load than at normal sea speed, and how might that influence lubrication needs?

✅ Before You Answer

• Decide whether lube oil rate should mainly follow RPM, load, or stay constant regardless of operating condition. • Ask yourself if cylinder lubrication systems on large low-speed engines are designed to reduce oil feed at low load to avoid bore polishing and cold corrosion. • Compare the likely average cylinder oil demand at sea (steady load) versus maneuvering (frequent low-load, speed changes) before picking the best option.