Question 24 AEL01 - Assistant Engineer - Limited

The Correct Answer is C **Why option C ("Lube oil pressure") is correct:** Lube oil pressure is the most critical parameter to check immediately upon starting any diesel engine. The lubricating oil forms a protective film between moving parts (like bearings, pistons, and camshafts). If the engine starts but oil pressure fails to build up within seconds (typically 3-5 seconds, depending on the engine), immediate and catastrophic metal-to-metal contact, resulting in severe damage (seizing or bearing failure), will occur very rapidly. Therefore, the operator's primary focus after ignition must be confirming adequate lube oil pressure. **Why the other options are incorrect:** * **A) Exhaust temperature:** While important for monitoring combustion efficiency and load, exhaust temperature takes time to stabilize and rise significantly (especially when the engine is unloaded). Checking it immediately upon start-up is less time-critical than ensuring lubrication. * **B) Lube oil level:** The level should ideally be checked *before* starting the engine (pre-start inspection). Once the engine is running, the oil is circulated, making an immediate and accurate level reading difficult or misleading. The immediate danger lies in lack of pressure, not just level. * **D) Water level in the expansion tank:** Cooling water level is crucial, but overheating (due to low water level) takes minutes to hours to cause significant damage. A catastrophic failure due to lack of lubrication (pressure) occurs in seconds. Therefore, cooling system checks are secondary to lubrication pressure upon immediate start-up.