# Noisy AC 20 filter



## ScarletFire (Nov 4, 2012)

So, I have this AC20 filter that's quite noisy. I got it free, so didn't expect it to be perfect. I rinsed the impeller, but it didn't decrease the amount of noise that it was making, so I made this solution. There's even cardboard on the underside. Before I start putting fabric or styrofoam around it, is there some other solution? I've heard that changing the impeller could work, but I want to limit the cost.


----------



## pyrrolin (Jan 11, 2012)

Pull the impeller out and clean inside where the magnetic part goes. I find dirt builds up in there and makes them noisy. I use a baby bottle scrubber thas has one end for nipples that works fairly well at getting in there


----------



## bob123 (Dec 31, 2009)

If you have another filter remove the motor from one and try it in the other to see if it makes a difference, all AC motors are the same. If you have another AC20 try and change impellers to see if noise is any less, if no change purchase a new impeller at LFS or ask on the forum buy and sell section.


----------



## cliff (Aug 30, 2010)

After you clean it like pyrrolin suggested (I like to use cotton swabs for that), take a look at the hole in the magnet of the impeller, if it's worn/not completely round - you'll have noise. I also had one go noisy from a worn shaft (granted the filter well over 10yrs old). Replaced the shaft and impeller, and was back to as good and quiet as new.

These things are nearly impossible to kill, worth throwing parts at IMO.


----------



## ScarletFire (Nov 4, 2012)

cliff said:


> After you clean it like pyrrolin suggested (I like to use cotton swabs for that), take a look at the hole in the magnet of the impeller, if it's worn/not completely round - you'll have noise. I also had one go noisy from a worn shaft (granted the filter well over 10yrs old). Replaced the shaft and impeller, and was back to as good and quiet as new.
> 
> These things are nearly impossible to kill, worth throwing parts at IMO.


By the way, does the impeller refer to the white spinning part, or the magnetic part attached to the white spinning thing? And is the shaft the magnetic part, or the metal piece that goes through the magnetic part which is attached to the motor?

If the inside of the motor isn't smooth, is it still worth it to replace the motor?


----------



## cliff (Aug 30, 2010)

The impeller is the while spinning part and the magnet (they should be attached together). 
pic here of a replacement one

The metal piece going through the magnet is the shaft.

I don't know what a replacement motor is worth, but if the plastic was all worn/scratched up - it would likely be a candiate for the spare parts bin IMO (unless the motor was loaded with a new impeller and not too expensive), otherwise I would likely replace it with a new one.


----------



## BillD (Jun 5, 2006)

Before replacing the impeller. pull the shaft and check it for wear. They tend to wear before the impeller and are cheaper to replace.


----------



## Mlevi (Jan 28, 2012)

BillD said:


> Before replacing the impeller. pull the shaft and check it for wear. They tend to wear before the impeller and are cheaper to replace.


True.

I lightly sanded the shaft (mine had rust spots), and then lubricated with petroleum jelly. It reduced the noise quite a bit. Wasn't as good as new, but, as a stop gap solution, it worked. The noise went from sounding like a grinder to a low hum. I am not sure if petroleum jelly is safe or not, but my fishes are doing okay in that tank. I have heard that silicone oil is better (and safer?) for lubricating aquarium parts, but never tried it myself.

Replacement motors for AC from LFS are worth close to the price of the filter itself. I eventually got a replacement from this forum. They come up pretty regularly. I think CanadaMoe had one advertised recently.

Al.


----------



## Ryan.Wilton (Dec 12, 2012)

The impeller may not need to be replaced at all, generally it's just a bit of sand or debris within the impeller that causes the problems. I had this same issue with a lot of aquaclear filters. Just clean the impeller and it should work fine.


----------



## Fishfur (Mar 4, 2012)

Fwiw, replacing an AC impeller is not a big investment. Around 10-12 bucks + tax at most stores. Might be cheaper online, but then you pay shipping. Motors cost more, but may often be found used. I've been able to buy a used AC, missing many of the parts, but with a motor, for much less than the cost of a new motor and the motor was just fine on it. All of the models, at least up to the AC70, use the same motor. It's just different impellers for each model.

For some reason, it does not appear to be possible to buy the plastic blade part of the impeller assembly alone. They only seem to make that part available with the magnet that it fits onto. Most stores seem to carry them, because they so popular.

Shafts you can buy separately and as BillD said, they are cheaper than an impeller would be.

I find a small stiff paint brush, [ I use a small, round one, from an art store, it's intended for painting with acrylic tube paint], is one of the best tools for cleaning out the impeller well. All kinds of gunk can build up in there, even fine gravel can get in there and really mess things up. Needs to be cleaned out regularly.


----------

