Goulds Pumps 3409 - IOM - Manual (Page 37)

3409 IOM 11/04
37
Problem Item Probable Cause Remedy
Pump
Operates
For a Short
Time, Then
Stops 30 Insufficient NPSHA. See item 17.
31 System head too high. See items 4 & 10.
Pump
Takes
Too Much
Power
32
Head lower than rating; thereby pumping too much
liquid.
Machine impeller’s O.D. to size advised by factory, or reduce speed.
33 Cavitation. See item 17.
34 Mechanical defects. See items 18, 19, 21, and 23.
35 Suction inlet not immersed. See item 20.
36
Liquid heavier (in either viscosity or specific
gravity) than allowed for. Use larger driver. Consult factory for recommended size.
Test liquid for viscosity and specific gravity.
37 Wrong direction of rotation. See item 6.
38 Stuffing box glands too tight.
Release gland pressure. Tighten reasonably. If sealing liquid does
not flow while pump operates, replace packing.
39
Casing distorted by excessive strains from
suction or discharge piping. Check alignment. Examine pump for rubbing between impeller and
casing. Replace damaged parts. Re-pipe pump.
40
Shaft bent due to damage — through shipment, op-
eration, or overhaul.
Check deflection of rotor by turning on bearing journals. Total
indicator run-out should not exceed .002" on shaft and .004"
on impeller wearing surface.
41 Mechanical failure of critical pump parts.
Check wear rings and impeller for damage. Any irregularity in these
parts will cause a drag on shaft.
42 Misalignment. Realign pump and driver.
43 Speed may be too high. Check voltage on motor. Check speed versus pump nameplate rating.
44 Electrical defects.
The voltage and frequency of the electrical current may be lower than
that for which motor was built, or there may be defects in motor. The
motor may not be ventilated properly do to a poor location.
45
Mechanical defects in turbine, engine or other type
of drive exclusive of motor.
If trouble cannot be located consult factory.
5