A: The pump must be primed and vented. First, open the inlet valve, then use the vent valve to expel all air from the pump casing, ensuring it is completely filled with liquid. Dry running is strictly prohibited, as it will quickly damage the mechanical seal and bearings.

A:​ Troubleshoot in the following order:

Cavitation / Air Ingestion (Most Common):

Check for air leaks​ in the suction line.

Check if the suction lift is too high.

Blockage:

Check for clogging of the inlet strainer, foot valve, or impeller passages​ by debris.

Rotation Direction:

Perform a bump start to verify the motor rotation direction is correct (reverse rotation will result in little to no flow).

A:​ Primary causes include:

Mechanical Issues:

Misalignment​ between the pump and motor shafts.

Worn bearings.

Unbalanced impeller.

Operational Issues:

Cavitation​ (Insufficient NPSH – Net Positive Suction Head).

Air entering the pump or pump running dry (“cavitation”).

Foundation Issues:

Loose foundation bolts.

A:

Bearing Overheating:

Insufficient lubricant (oil/grease).

Emulsified or degraded lubricant.

Bearing failure/damage.

Mechanical Seal Leakage:

Dry running of seal faces (lack of flush fluid).

Interruption of cooling water.

Aging or worn seal components.

Note for Packing Seals:​ A slight, controlled leak is normal for lubrication and cooling. The typical acceptable leak rate is 10-20 drops per minute.

A:​ When the ambient temperature falls below 0°C (32°F), it is essential to completely drain​ all residual water from the pump casing, cooling water jackets, and associated piping after shutdown. This prevents the water from freezing and expanding, which can crack the pump body, impeller, or pipes. This is especially critical for pumps that will be idle for extended periods.