Secondnature Whisper Power Filter - Grinding noise

Also you can take the impeller apart roll the shaft on the table to see if its warped then look down the hole the shaft rides through down the magnet. Hold the magnet up to the light look down the empty shaft hole it should be round not oval, Also place the shaft back in the magnet and wiggle from side to side, their should be very little play and no slop.

Of course you never said you scrubbed out the motor hole the magnet and impeller assembly rides in, maybe their is a bunch on gunk and sand in there.
 
I did clean out the hole that it sits in. So I'm pretty sure that isn't it. There wasn't much gunk there to begin with. The shaft does have quite a lot of wiggle room in the magnet, which might be the issue, and the magnet looks like it is warped on one side - it's got a small concave area on it. I guess we'll know for sure if the impeller is the problem when the new one arrives. I'm assuming early next week since I did not pay for expedited shipping.
 
You may also want to order a new shaft a I have rarely seen a magnet worn that also diden't need a new shaft. Shaft ware is sometimes obvious if there are nicks, groves or gouges but some times its not obvious. If the shaft is worn even a little it will prematurely ware out the new magnet fast. You know becasue there should be no play between the magnet and shaft.

Oh and shafts are much much cheaper then the impeller usually $2.
 
same whisper secondnature 3 as rainbow charmer but it leaks a little from the bottom where the motor fits in. O ring seems to be fine, not cracked or worn. But motor seems a little loose. can I use a bit of vasoline around O ring like recomended with the magnum canisters. Afraid this might get in tank.
 
replace the o-ring may not look bad but if its not fitting snug its worn and needs replaced, and yes you can rub a little vaseoline all around the o-ring it may stop your leak and if it does you know the o-ring needs replaced. wont harm your tank.
 
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