Cavitation – Hale 80FC User Manual
Page 75

75
Pump Ends
p/n: 029-0020-61-0
T r ou b les h oo tin g
❑
Engine Speeds Too
HIGH for Required
Capacity or Pres-
sure - continued.
Pump is approaching
“Cavitation.”
• Gate the discharge valves to allow pressure to increase. This
reduces the flow.
• Reduce the throttle opening to the original pressure setting.
• See “Appendix F: Cavitation” on page 145.
Worn pump impeller(s)
or clearance rings.
• Repair and/or replace as needed. See Section 6 “Repair” on page
77.
Impeller blockage.
• A blocked impeller can prevent loss of both capacity and pressure.
• Back flushing the pump from discharge to suction may free the
blockage.
• Removing half the pump body may be necessary - this is consid-
ered a major repair.
Cavitation
(Pump beginning to
cavitate.)
Note: Also see
“Appendix F: Cavita-
tion” on page 145.
Discharging more water
than the pump is taking
in.
• Increase the flow into the pump with more and/or larger intake
lines.
• Gate the discharge valves to reduce flow and maintain pressure.
Air leak.
• Verify that the air bleeder on the suction tube is NOT open.
• Locate and eliminate all air leaks during maintenance.
Drafting too high.
• Verify lift hose, hose friction, water temperature and other lift limit-
ing factors are reduced or eliminated.
• Locate the pump closer to the water source.
Water temperature too
high.
• Reduce volume discharge by lowering the RPM or gating the dis-
charge valves.
• Locate a source of cooler water.
Suction hoes diameter
is too small for the vol-
ume being discharged.
• Use a large suction hose.
• Shorten the total length by removing one length of hose.
• Reduce volume of discharge.
Restriction in suction
line at strainer.
• Remove any debris restricting entrance of water at the strainer.
• Also see Section 4 Preventive Maintenance, heading “Intake
Relief Valve Does
Not Relieve Pres-
sure When Relief
Valves are Closed.
Chart continued on
next page.
Incorrect setting of con-
trol (PMD) Valve.
• Check and repeat proper procedures for setting relief valve
system.
• See Section 3 Operation, heading 3.5 “Relief Valve Procedures” on
Relief valve
inoperative.
• Possibly in need of lubrication. Remove valve from pump, disman-
tle, clean and lubricate.
• Refer to relief valve manual and follow maintenance instructions for
disassembly, cleaning and lubrication.
Condition
Possible
Cause
Suggested Corrective Action
Figure 5-2: Troubleshooting Chart