Product Manual

Owner’s Manual for Dry-Prime Diesel Trash Pumps 59
Troubleshooting
Section 5 Troubleshooting
Pump Troubleshooting Guide
Symptom Possible Cause
No discharge 1,2,3,4,5,7,8,9,10,17,18,19,20,37
Reduced capacity 2,3,4,5,7,8,9,10,11,17,19,20,21,38,39,40,47
Reduced pressure 5,7,8,11,13,18,19,38,39,40,47
Loss of prime 2,3,4,7,10,11,20,21,22,23
Power consumption excessive, engine runs hot 6,12,13,17,18,19,24,33,34,35,36,37,38,41,42,43,44
Vibration and noise
2,4,9,10,14,15,17,26,27,28,29,30,31,32,33,34,35,36,
39,40,41,42,43,44,48
Seal: excessive leakage, short life, seal housing
overheating
22,23,25,33,34,35,36,41,44,45,46
Bearings: overheating, short life, noise 26,27,28,29,30,31,32,33,34,35,36,41,42,43,44
Pump overheating, seizes 1,8,9,14,33,34,35,36,41,42,43,44
Corrosion, erosion, pitting, oxidation or other loss of
material
7,8,11,14,15,16
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Pump not primed
Suction line not filled
Air pocket in suction line
Suction inlet or foot valve obstructed,
insufficiently submerged, or too small
System head higher than pump
design head
System head lower than pump
design head
Insufficient Net Positive Suction
Head (NPSH)
Parallel pump application is incorrect
Suction pressure to vapor pressure
below minimum
Suction lift too high
Excess vapor in pumpage
Specific gravity of pumpage housing
different than design
Viscosity of pumpage different than
design
Operation at below rated capacity
Cavitation
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
Electrolysis
Impeller obstructed
Rotation direction wrong
Low speed
Air leak into suction line
Air leak through mechanical seal
Seal fluid contaminated, hot or
insufficient
Seal fluid system not vented
High speed
Mechanical seal insufficient
Bearing housing excessively
cooled
Low oil pressure (oil lube bear-
ings)
Improper or poor lubrication
Lubrication defective
Dirt in lubrication/bearings
Moisture in lubricant/bearing
housing
Lubricant excess
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
Pipe strain
Temperature growth
Misalignment
Coupling improperly installed
Impeller installed backwards
Worn wear rings
Impeller damage
Improper balance (after repair)
Bent shaft
Excessive thrust
Rotational element dragging
Worn or incorrectly installed
bearings
Mechanical seal not properly
set, O-rings damaged or
hardened
Shaft scored at seal
Volute O-ring
Foundation not rigid or settled