Delavan M125 - Manual (Page 6)

1228 Chestnut Avenue • Minneapolis, MN 55403 Delavan Ag Pumps
Document HD Magnum Install 3.15.06
HD Magnum Series
6
Troubleshooting Guide
Problem Causes and Remedies
Pump Doesn’t Deliver Flow Suction strainer is clogged
• Clean strainer
Loss of prime
• Make sure pump is below the liquid level
• Install anti-vortex fitting in tank
• Open vent line from the top-most plug on the pump volute to
bleed off air
• Check suction line for leaks
Collapsed suction hose
• Replace with wire reinforced hose
• Use larger diameter hose
Impeller clogged
• Remove volute casing and check for foreign material
Leakage Between Centrifugal Pump Pump seal is leaking
and Hydraulic Motor • Disassemble volute and impeller and replace seal
Hydraulic motor seal is leaking
• Remove from centrifugal pump and replace seal on the motor
Lack of Pressure from Centrifugal Pump Insufficient Motor Speed
• Adjust hydraulic flow control
Make sure pump is fully primed
• See “Loss of prime” above
Check for clogged strainers
Excessive restriction on inlet hoses
• Use larger size hose, ball valves and strainers
Bypass screw is turned out too far (open center systems)
• Re-adjust bypass screw setting by turning it in
Cannot Reduce Spraying Pressure Excessive motor speed
to Desired Range • Adjust hydraulic oil flow to motor, using flow control
Motor on open center systems is too small
• Check selection guide for correct motor
Hydraulic Fluid Becomes Too Hot Check hydraulic fluid levels
Check hydraulic filters and replace if clogged
Incorrect motor application
• Check selection guide for correct motor application
Check hydraulic hose sizes
• Hoses should be at least 1/2”
• Use 3/4” for hose runs over 15 ft. or flow
rates higher than 15 GPM
Check temperature with gauge
• Make sure temperature is 160° or less
Hydraulic Motor Operates Erratically Liquid pressure varies
• Check for air leaks in inlet of pump
• Check for proper fluid levels in tractor
• Check for hydraulic motor wear
• Make sure tractor hydraulic system has clean filters