Centrifugal Pump Not Pumping

Centrifugal Pump Won’t Pump — Industrial Troubleshooting Field Guide

When a centrifugal pump is running but flow is low, pressure is weak, or no liquid is moving at all, the problem is not always the pump itself.

The Shepherd Manuals Centrifugal Pump Won’t Pump — Industrial Troubleshooting Field Guide is a focused 22-page quick-reference PDF for industrial mechanics, millwrights, maintenance technicians, reliability personnel, apprentices, and instructors.

This guide is built around a common plant-floor problem:

“The motor is running, but the pump won’t pump.”

Instead of replacing parts without a diagnosis, this guide helps the technician work through the system logically and identify whether the problem is caused by the suction side, loss of prime, air leakage, rotation, speed, the discharge system, or the internal condition of the pump.

Topics Include

• How centrifugal pumps produce flow
• Pump not primed
• Loss of prime
• Suction-side restrictions
• Plugged strainers
• Partially closed valves
• Collapsed suction hose
• Excessive suction lift
• Suction air leaks
• Wrong pump rotation
• Incorrect pump speed
• Motor running but no flow
• Low flow
• Low discharge pressure
• Cavitation
• NPSH-related problems
• Impeller blockage
• Impeller wear or damage
• Excessive wear-ring clearance
• Internal recirculation
• Mechanical seal problems
• Bearing problems
• Shaft and coupling issues
• Alignment problems
• Pump loses prime after shutdown
• Troubleshooting by timing and symptom

Full-Page Troubleshooting Flowchart

The guide includes a large, easy-to-follow troubleshooting flowchart that walks the technician through:

PUMP RUNNING → PRIME → SUCTION → AIR LEAKS → ROTATION → SPEED → DISCHARGE → INTERNAL PUMP CONDITION

The goal is to help the technician find the actual cause before unnecessary pump removal or component replacement.

Practical Field Tools Included

• Symptom — Cause — Action tables
• Field inspection checklist
• Pump measurement record sheet
• Corrective-action guidance
• Real-world case studies
• Guidance on when the pump should be stopped immediately

Built for Real Maintenance Work

This is not a general pump-theory textbook. It is a focused troubleshooting reference designed for the plant floor.

Use it when dealing with:

• No flow
• Low flow
• Low pressure
• Repeated loss of prime
• Cavitation
• Suction problems
• Pump noise
• Poor performance after maintenance

The troubleshooting method follows:

SYMPTOM → VERIFY PRIME → CHECK SUCTION → VERIFY ROTATION/SPEED → CHECK DISCHARGE → INSPECT INTERNAL CONDITION

Format: PDF Digital Download

Length: 22 pages

Suggested Price: $9.99

Publisher: Shepherd Manuals

Practical. Technical. Trusted.

Find the cause. Take the correct action. Restore flow.