Griswold 811 - Troubleshooting

GRISWOLD PUMP COMPANY Pump Operation Page 20
Installation, Operation and Maintenance Manual
Griswold Model 811
Griswold Pump Company Pump Operation Page 22
Troubleshooting
If problems are encountered during start-up or pump operation, refer to the folowing table for
likely causes:
Problem Likely Cause Remedy
Pump not primed Re-prime pump, check that suction
line is full of liquid
Suction line obstructed Remove obstruction
Impeller clogged Remove obstruction
Wrong direction of rotation
Note - Possible severe damage!
Check rotation, change if necessary
Foot valve or suction pipe has
inadequate submergence
Check suction source for vortexing,
correct as necessary
No liquid delivered
Suction lift too high Review/revise level on suction
Air leak through gasket Replace gasket, tighten connections
Air leak through stuffing box
Inspect packing/mechanical seal,
add pressurized flush if necessary
Impeller partially clogged Remove obstruction
Excessive impeller clearance Adjust impeller clearance
Inadequate suction head Review/revise design
Pump does not produce rated flow or
head
Worn or damaged impeller Inspect/replace as necessary
Pump improperly primed Re-prime pump
Air or vapor in suction line
Review/revise suction piping to
eliminate air pockets
Pump starts then stops pumping
Air leak in suction line Check gaskets, repair leak
Improper alignment Re-align pump and driver
Improper lubrication
Check lubricant for applicability and
level/quantity
Bearings run hot
Bearing cooling not working Check cooling water line(s)
Improper alignment Re-align pump and driver
Partial impeller clog/imbalance Remove obstruction
Broken or bent impeller or shaft Replace as necessary
Foundation not rigid
Tighten hold-down bolts of base,
pump and motor. Recheck
alignment.
Worn bearings Replace as necessary
Suction and/or discharge piping not
anchored correctly
Review design, modify as necessary
Pump is noisy or vibrates
Pump cavitation
Review suction system, correct
problem(s)
Packing gland improperly adjusted Tighten gland nuts
Stuffing box not packed properly Check, re-pack as necessary
Shaft sleeve scored, ridged Replace as necessary
Excessive stuffing box leakage
Worn mechanical seal Replace as necessary
Actual head lower than design
Throttle discharge valve slightly,
trim impeller. Review design
Liquid heavier than expected Review design
Stuffing box packing too tight Re-pack pump
Excessive power required
Rotating parts binding Check pump internals