Question 89Motor Plants - 1st Asst/Chief

70% to pass

You are onboard a vessel with a slow-speed crosshead type engine. The fuel just received has a significantly lower sulfur content than the previous bunkers. Which of the following would be a concern due to the reduced sulfur content?

AFuel injection temperature
BBase number of the cylinder oil
CFuel supply system pressure
DPurifier gravity disk size
AI Explanation

The correct answer is B) Base number of the cylinder oil. The reduced sulfur content in the fuel can lead to a decrease in the base number (BN) of the cylinder oil. Cylinder oils are formulated with detergent and dispersant additives, including alkaline compounds, to neutralize the acidic byproducts of combustion. With lower sulfur fuel, there is less acid formation, requiring a lower BN cylinder oil to prevent excessive alkali buildup in the engine. The other options are not directly affected by the change in fuel sulfur content.

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