Technician A says bronze valve guides wear better than iron ones. Technician B says to use SAE 90 oil as a lubricant when machining bronze. Who is right?

Question

Quizplus · Accepted Answer

Bronze is a softer metal than iron, so it will wear more quickly than iron. SAE 90 oil is a heavy oil that is not suitable for lubricating bronze. A lighter oil, such as SAE 30, should be used.

Technician a Says Bronze Valve Guides Wear Better Than Iron