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eagleONE
11/26/2007, 02:26 AM
What to do? I have an old dolphin pump from my euroreef es53- I've modded the skimmer to recirc. Now I'm finding it too loud. I guess I got use to the silence for awhile... Is there any way I can silence this sucker? I even thought of building a sound box. I don't know. Any suggestions and input please. Thanks

Jay

thor32766
11/26/2007, 09:59 AM
maybe putting a box around it might help. I know when I enclosed my tank the pumps got quite a bit lower.

JaredWaites
11/26/2007, 10:05 AM
Well lets not stray from the topic, the pump is getting loud could be a real issue, because you did say it was an old pump.

Suppose its bearings, or windings?

eagleONE
11/26/2007, 02:49 PM
Suppose it's the bearings... so what do I do? Lube it?

Forgive me but what are windings?

Thanks
Jay

DeathWish302
11/26/2007, 03:36 PM
Windings is the copper wired "wound" around the "motor" (some type of frame that holds the wire and has a commutator for the brushes with 2+ bearings) to create the polarized switching that creates the pressure change to "pump" water. If you haven't encountered "windings" before, I suggest not even thinking about "rewinding" ANY motor for any use. It's not as easy as wrapping wire around 4 posts in an alternating pattern.

Most all pump bearings are sealed, while I'm sure a few use the water as the "lube". You'll find in most instances if you try to replace sealed bearings, it may cost similiar to a new pump unless they are an "off-the-shelf" item. Manufacturers buy in bulk and you won't get the same discount as they do, so if it's the bearings I'd say don't spend too much time looking into replacements unless offered by the manufacturer.

Is the pump suffering from cavitation? If so, that will make a huge jump in the dB during operation and destroy a pump quickly.

Adam
11/26/2007, 03:57 PM
Hi all,

Powerhead pumps don't work like a motor with windings and an armature. They have a permanent magnet rotor that is turned by an alternating magnetic field.

The rotor spins about a shaft on bushings imbedded in the rotor.

Generally, when a powerhead type pump gets noisy, the bushings have worn a "keyhole" and the rotor is spinning off center. Eventually, this can wear the casing of the pump and short. Cheaper pumps use plastic bushings that are much more prone to this kind of wear. Dolphins, sedras and gen-x are like this. I am pretty sure that eheims and ocean runners use ceramic bushings that are much more durable.

I had to replace several pumps on my euro-reef for this kind of wear before I finally modded it to accept an ocean runner. Replacement impeller/rotors are available on line if you want to replace it.

HTH

Adam

eagleONE
11/26/2007, 04:25 PM
So I opened it up and took a look at it... and the shaft is spinning off center. It only does this once in awhile. After opening it then placing it back in, the pump was quieter. Where is this bushing? Thanks for the info I'm learning a lot!

eagleONE
11/26/2007, 04:40 PM
well, the rotor seems to spin correctly but something is making it stop for a split second in its spins... and the noise I think I'm dealing with is vibrational...

eagleONE
11/27/2007, 02:44 AM
any way to deal with this chuckling sound?

hllywd
11/27/2007, 04:09 PM
I had an older Dolphin pump, sent it to them for new seals because the back of the pump had a minor leak. They came back offering to sell me a rebuilt pump since mine had bad bushings in the motor, bad seals, cracked impeller, and even something wrong with the volute.... all for a bargain basement $249.

The regular seals on dolphins have a service life of 3 - 7 years (per Dolphin). There are 4 small bolts that go through the motor holding it together and the pump housing to the front of the motor. One of the bolts on mine was siezed and snapped off when I tried to remove it which in turn made it impossible to remove the motor from the pump housing without further damage.

The motor bushings in each end of the motor, are made of bronze and are probably permenantly lubed but will wear out over time and most likely aren't user replacable.

Mine was nearly silent in regular operation other than the sound of the internal motor fan. Depending on your noise it could be several things. If you think its vibration related have you looked at the impeller? Is it cracked or broken?
Look at the motor shaft where it goes through the pump seal, is there any rust there to indicate a leak? If so, and this was the case with mine so Dolphin said, the rust can expand the shaft inside the pump impeller causing a crack although that didn't cause mine to be noisy or vibrate.

Worn bushings could also cause excess noise and is likely terminal for at least the motor if not the pump. Take the front cover off the pump housing and see if there is any side to side play between the shaft and the front bushing of the motor.

Hope some of that helps...
Tim

eagleONE
12/30/2007, 01:07 AM
Nothing is broken. My only observation is that the magnet is rattles when running. I'm no real expert so I'm not sure what to do.

I've had this vibrating problem when i had it in the sump. My solution at the time was to place a bag of sand to quiet it. Now that I've modified to run externally (for recirc) , I've come to find that the pump is a lot louder than expected.

five.five-six
12/30/2007, 11:06 AM
I am dealing with this on a pump for a ASM mini-G, I suspect that the impeller shaft and the inside of the impeller are worn. have you pulled the shaft and impeller out? if the shaft is ceramic, be careful, there is enough force in the magnet many times to break the shaft if the impeller slips out of your hand

the impeller should have almost no detectable play on the shaft