Well-Fed Sprinkler System: Some Zones Work, Pump Loud

Well-fed system with old, loud pump. Some zones work, others don't. Planning pump replacement; asks about priming process.

Pump Noise Indicates Wear

Loud operation suggests bearing or impeller wear. Cavitation (gravelly sound) indicates insufficient water supply—well screen plugging or suction leak.

Critical Checks Before Replacement

• Suction line air leaks: Even a pinhole destroys prime. Inspect all joints from well to pump.
• Well screen/foot valve: May be fouled.
• Zone balance: Do working and non-working zones have similar head counts? If non-working zones have more heads, the pump may not supply enough flow.

Priming New Pump

1. Fill pump casing completely via priming plug.
2. Open discharge valve slightly.
3. Start pump; close discharge once steady flow establishes.
4. Ensure foot valve holds prime when pump stops.

Fix suction leaks first—a new pump won't overcome them.