Skimmer Pump Not Working

[usvi diver]

I recently bought an ASM G-2 protein skimmer off E-bay. I took it apart and gave it a vinegar/water bath. Now it is back together but the pump runs intermittently. It seems to run free with the end cap (suction) off but once that is back on, it will only run for 30 seconds or so. It is a Sedra KSP-3500.

I have the pump apart again and in another vinegar/water bath but I don't know what else to do other than wipe the parts down after that. Any suggestions would be appreciated.

Thanks!

 

[sewer urchin]

I don't have a ton of experience with those bigger skimmers. However, that being said, my first (and only) thought is that something may be up with the impeller.

The sedra pumps have a ceramic shaft for impeller and if you stare cross eyed at them they can break.... easily. I broke my first one putting the volute cover back on, it irritated me to no end because I knew that all the parts were fine, that is before I broke it ;-)

A while back someone posted about replacing the ceramic shaft with a carbon rod, do a search for the thread, I believe that they picked it up at a hobby store. If you can't find it let me know and I think that I saved the info somewhere around here.

 

[usvi diver]

Thanks for the info Urchin!

I ordered a new impeller and hopefully that will fix the problem. I was looking at the old one again and I can feel a raised spot on the magnet. It has a lot of marks and scuffs there also. I don't know if magnets can go bad on these but this one is not very cylindrical.

 

[bluespot]

Scuffed and damaged magnets definitely drag inside the pump and can cause malfunction. That is usually what seems to go bad on my pumps.

 

[ichthyoid]

Often a particle of some sort or another gets in between the magnets and causes problems.

That bump on the impeller is your 'smoking gun', IMO.

Replacement usually solves it, unless the pump casing has been worn through. That can be dangerous.

 

[1mbrews8]

Tried blowing in the air intake on top of the skimmer? sometimes that helps it getting unstuck

 

[bluespot]

Very true, but the damaged magnet will probably cause it to stop again at some point imo.

 

[usvi diver]

I installed a new impeller and now it works like a charm. Thanks for all the help.