Pump Problems

Unresistible Blue · 12/04/2008, 05:30 AM

I use an Iwake 100 return pump. The amount of water the pump moves has decreased over time. I know that the pump has been in situations where it was cavitating for hours - my guess is that that is about as bad as letting the pump run dry.

If letting it cavitate damaged the pump, is it the lastic head that fets worn out or is it the pump itself?

Any way to fix the pump to restore the flow?

Paco · 12/04/2008, 07:48 AM

First thing to do is remove the pump, disassemble the volute (all the stuff in front of the motor -- the parts where the water enters, exits, impeller, etc) and soak in Vinegar to dissolve any calcium deposits. Then inspect for damage. If it's like other pumps, you can simply replace the volute or certain parts of the volute if it's damaged. Pay special attention to the shaft to see if it's burned.

AZDesertRat · 12/04/2008, 08:27 AM

Cavitation is just as damaging as pumping sand if not more so. look at the impeller, magnet and the volute or pump housing for singns or rough surfaces. scoring or pitting. All will reduce the pumping capacity due to eddies and non laminar flows because of the roughness.
At best it may just need a new impeller assembly, at worst a new pump. I don't know if you can buy a replacement pump end for an Iwaki but its probably as expensive as a pump.

12/04/2008, 05:30 AM	#1
Unresistible Blue Registered Member Join Date: Mar 2002 Posts: 1,029	Pump Problems I use an Iwake 100 return pump. The amount of water the pump moves has decreased over time. I know that the pump has been in situations where it was cavitating for hours - my guess is that that is about as bad as letting the pump run dry. If letting it cavitate damaged the pump, is it the lastic head that fets worn out or is it the pump itself? Any way to fix the pump to restore the flow?

12/04/2008, 07:48 AM	#2
Paco Move Don Join Date: Sep 2008 Location: Miami, FL Posts: 1,210	First thing to do is remove the pump, disassemble the volute (all the stuff in front of the motor -- the parts where the water enters, exits, impeller, etc) and soak in Vinegar to dissolve any calcium deposits. Then inspect for damage. If it's like other pumps, you can simply replace the volute or certain parts of the volute if it's damaged. Pay special attention to the shaft to see if it's burned. __________________ Fish are nitrate factories. Remove them and watch your nitrates come down. Current Tank Info: 120 mixed reef

12/04/2008, 08:27 AM	#3
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Cavitation is just as damaging as pumping sand if not more so. look at the impeller, magnet and the volute or pump housing for singns or rough surfaces. scoring or pitting. All will reduce the pumping capacity due to eddies and non laminar flows because of the roughness. At best it may just need a new impeller assembly, at worst a new pump. I don't know if you can buy a replacement pump end for an Iwaki but its probably as expensive as a pump.