Question 10 OSE01 - Chief Engineer - OSV

The Correct Answer is D **Explanation for Option D (Correct Answer):** The air starter motor requires lubrication, which is typically provided by an in-line lubricator (mist generator) that injects a small, controlled amount of oil into the compressed air supply line. This lubricated air powers the starter, and the air/oil mixture exits via the exhaust port. If the **in-line lubricator needle valve degree of opening is excessive**, it allows too much lubricating oil to enter the air stream. This excess oil manifests as an observable, excessive amount of oil mist exiting the air starter exhaust port, thus accounting for the reported condition. **Explanation for Incorrect Options:** **A) The in-line lubricator siphon tube is excessively restricted:** The siphon tube draws oil from the reservoir. If it were restricted, it would reduce the amount of oil entering the airstream, resulting in *insufficient* lubrication and *less* oil mist exiting the exhaust, not an excessive amount. **B) Excessive oil within the engine's cylinders is being pumped:** The air starter exhaust is physically separate from the main engine cylinders and combustion spaces. Oil within the cylinders might cause issues like hydro lock or blue smoke from the main engine exhaust once running, but it would not contaminate or pressurize the air starter exhaust port with excess oil mist. **C) The in-line lubricator needle valve degree of opening is insufficient:** Similar to restriction (Option A), an insufficient opening would restrict the flow of oil into the compressed air. This would lead to *insufficient* lubrication and a *reduced* amount of oil mist exiting the exhaust, contrary to the condition described (excessive oil mist).