LN

Inspect mechanical seal faces for wear patterns and verify cooling/barrier fluid levels (where applicable). Check for weeping at the seal chamber under operating pressure. Listen for seal-related noise (grinding, squealing) indicating imminent failure.

Monitor bearing temperature trends using infrared thermography. Check grease consistency and color (oxidation indicates overheating). Verify bearing preload and axial movement. Listen for abnormal noise (grinding, rumbling) indicating cage wear or spalling.

Measure clearance between impeller and casing wear rings using feeler gauges. Check for visible scoring or erosion patterns on impeller and casing surfaces. Monitor discharge pressure decline and capacity loss indicating internal bypass.

For VP (vacuum priming): verify ejector vacuum generation (typically 0.7-0.8 bar). For EP (electric priming): test motor operation and check priming pump discharge. Monitor initial prime time; exceeding 30-minute dry-run specification indicates air leak or priming pump degradation.

Check suction line pressure (NPSH available vs. required). Clean/inspect suction strainers for marine growth, scale, or debris accumulation. Listen for cavitation noise ('marbles in pump'). Inspect impeller for pitting or erosion patterns typical of cavitation damage.