Goulds Pumps 3700 - IOM - Manual (Page 104)

Troubleshooting
Troubleshooting
Operation troubleshooting
Symptom Cause Remedy
The pump is not delivering The pump is not primed. Re-prime the pump and check that the pump and
liquid. suction line are full of liquid.
The suction line is clogged. Remove the obstructions.
The impeller is clogged. Back-flush the pump in order to clean the impeller.
The shaft is rotating in the wrong direction. Change the rotation. The rotation must match the
arrow on the bearing housing or pump casing.
The foot valve or suction pipe opening is not Consult an ITT representative for the proper sub-
submerged enough. mersion depth. Use a baffle in order to eliminate
vortices.
The suction lift is too high. Shorten the suction pipe.
The pump is not producing The gasket or O-ring has an air leak. Replace the gasket or O-ring.
the rated flow or head. The stuffing box has an air leak. Replace or readjust the mechanical seal.
The impeller is partly clogged. Back-flush the pump in order to clean the impeller.
The clearance between the impeller and the Adjust the impeller clearance.
pump casing is excessive.
The suction head is not sufficient.
Make sure that the suction-line shutoff valve is
fully open and that the line is unobstructed.
The impeller is worn or broken. Inspect and replace the impeller if necessary.
The pump starts and then The pump is not primed. Re-prime the pump and check that the pump and
stops pumping. suction line are full of liquid.
The suction line has air or vapor pockets. Rearrange the piping in order to eliminate air
pockets.
The suction line has an air leak. Repair the leak.
The bearings are running The pump and driver are not aligned properly. Realign the pump and driver.
hot.
There is not sufficient lubrication. Check the lubricant for suitability and level.
The lubrication was not cooled properly. Check the cooling system.
The pump is noisy or vi- The pump and driver are not aligned properly. Realign the pump and driver.
brates.
The impeller is partly clogged. Back-flush the pump in order to clean the impeller.
The impeller or shaft is broken or bent. Replace the impeller or shaft as necessary.
The foundation is not rigid. Tighten the hold-down bolts of the pump and
motor. Make sure the baseplate is properly
grouted without voids or air pockets.
The bearings are worn. Replace the bearings.
The suction or discharge piping is not an- Anchor the suction or discharge piping as neces-
chored or properly supported. sary according to recommendations in the Hy-
draulic Institute Standards Manual.
The pump is cavitating. Locate and correct the system problem.
The mechanical seal is leak- The packing gland is not adjusted properly. Tighten the gland nuts.
ing excessively.
The stuffing box is not packed properly. Check the packing and repack the box.
The mechanical seal parts are worn. Replace the worn parts.
The mechanical seal is overheating. Check the lubrication and cooling lines.
The shaft sleeve is scored. Machine or replace the shaft sleeve as necessary.
The motor requires exces- The discharge head has dropped below the Install a throttle valve. If this does not help, then
sive power. rated point and is pumping too much liquid. trim the impeller diameter. If this does not help,
then contact your ITT representative.
The liquid is heavier than expected. Check the specific gravity and viscosity.
The stuffing-box packing is too tight. Readjust the packing. If the packing is worn, then
replace the packing.
Rotating parts are rubbing against each other. Check the parts that are wearing for proper
clearances.
The impeller clearance is too tight. Adjust the impeller clearance.
102 Model 3700, API Type OH2 / ISO 13709 1st and 2nd Ed. / API 610 8/9/10/11th Ed. Installation, Operation, and Maintenance
Manual