NCCER Millwright Practice Exam 2025 - Free Millwright Practice Questions and Study Guide

To confirm that a mechanical seal is functioning correctly, checking for fluid leakage is a critical method. A properly functioning mechanical seal should effectively contain the fluid within the system, preventing leaks. If there is any fluid leakage, it indicates a failure in the seal, which may result from wear, misalignment, or deterioration over time.

While visual inspections for cracks can help identify obvious physical damage, they do not provide a comprehensive assessment of the seal's performance. Assessing vibration levels can offer insights into the overall condition of machinery but does not directly relate to the performance of the mechanical seal itself. Listening for grinding sounds might indicate issues with adjacent components or improper installation, but it does not specifically evaluate the seal's integrity. Therefore, checking for fluid leakage stands out as the most direct and effective method for verifying the operational status of a mechanical seal.