Upon conducting a machinery space round on a slow-speed main propulsion diesel, you detect a significant amount of oil discharge when blowing down the scavenging air receiver drains. What should you do?

Correct Answer: Option C — Notify the watch or duty engineer immediately.

Sudden or abnormal quantities of oil discharging from scavenging air receiver drains signal severe piston ring distress, cylinder over-lubrication, or scavenge fires. Immediate watch engineer notification is mandatory to prevent machinery damage.