SYMPTONS OF INTERNAL GEAR PUMP FAILURE AND ITEMS TO CHECK

HYDRAULIC
SYMPTON: Pump turns, but no flow
Possible System Issue	Possible Pump Issue	Possible Drive Issue
• NPSHa not sufficient • Air leaks into pump • Pump has run dry • Suction valve not open • Discharge valve not open • Clogged strainer • Supply tank empty	• Incorrect rotation • Incorrect head placement • Wrong clearance setting for application • Worn pump internals • Incorrect speed (lower speed)	n/a
SYMPTON: Low capacity
Possible System Issue	Possible Pump Issue	Possible Drive Issue
• NPSHa not sufficient • Air leaks into pump • Pump has run dry • Liquid temperature higher than expected • Pump running too fast for application • Abrasives present / parts not hardened • Suction valve partially open • Clogged strainer	• Incorrect head placement • Wrong clearance setting for application • Worn pump internals • Relief valve improperly set • Incorrect speed (lower speed)	• Drive incorrectly sized for horsepower requirement
SYMPTON: Pump will not develop sufficient pressure
Possible System Issue	Possible Pump Issue	Possible Drive Issue
• Air leaks into pump • Pump has run dry • Liquid temperature higher than expected • Suction valve partially open • Clogged strainer	• Incorrect head placement • Wrong clearance setting for application • Worn pump internals • Relief valve improperly set	• Drive incorrectly sized for horsepower requirement