Goulds Pumps 3910 11th ed. - IOM - Manual (Page 30)

TROUBLESHOOTING
30
3910-1
1th IOM 5/08
Problem Probable Cause Remedy
No liquid delivered.
Pump not primed.
Check that pump and suction line are full of liquid.
Reprime pump.
Suction line clogged. Remove obstructions.
Impeller clogged with foreign material. Back flush pump to clean impeller.
Foot valve or suction pipe opening not
sufficiently submerged. Consult factory for proper depth.
Use baffle to eliminate vortices.
Suction lift too high. Reduce suction lift.
Pump not producing
rated flow or head.
Air leak thru gasket. Replace gasket.
Air leak thru seal chamber. Replace or readjust mechanical seal.
Impeller partly clogged. Back flush pump to clean impeller.
Worn wear rings. Replace defective part as required.
Insufficient suction head.
Ensure that suction line shutoff valve is fully open
and line is unobstructed.
Increase suction head.
Worn or broken impeller. Inspect and replace if necessary.
Wrong direction of rotation.
Change rotation to concur with direction
indicated by arrow on bearing frame.
Pump starts then stops
pumping.
Improperly primed pump. Reprime pump.
Air or vapor pockets in suction line. Rearrange piping to eliminate air pockets.
Air leak in suction line. Repair (plug) leak.
Bearings run hot.
Improper alignment. Re-align pump and driver.
Improper lubrication. Check lubricant for suitability and quantity.
Insufficient cooling liquid. Check cooling system.
Pump is noisy or
vibrates.
Improper pump/driver alignment. Align shafts.
Partly clogged impeller causing imbalance. Backflush pump to clean impeller.
Broken or bent impeller or shaft. Replace as required.
Impeller out of balance. Balance impeller.
Foundation not rigid.
Assure uniform contact of pump and/or supports
with foundation.
Worn bearings. Replace.
Suction or discharge piping not anchored or properly
supported. Anchor per Hydraulic Institute Standards/
API RP 686 recommendations.
Pump is cavitating. Locate and correct system problem.
Excessive leakage from
stuffing box. Worn mechanical seal parts. Replace mechanical seal.
Overheating mechanical seal. Check lubrication and cooling lines.
Motor requires
excessive power.
Head lower than rating. Pumps too much liquid.
Consult factory.
Install throttle valve.
Cut impeller.
Liquid heavier than expected. Check specific gravity and viscosity.
Rotating parts bind. Check internal wear parts for proper clearances.