used return pump....still good????

[stickysheets217]

so i got a 180 gallon tank w/a 40 gallon wet/dry sump that came with a 320 gph return pump..... because it was just a cheap one i replaced it with a 1270 gph coralife pump, what i am getting at is the pump i replaced has been sitting out 4 awhile and developed rust in it..... what can i do to insure that if i use it on a smaller tank that it wouldnt affect anything, or is it pretty much just a loss

 

[snakeblitz33]

It's a loss.
Shouldn't use any rusted up parts. If you do, you should replace all of the bolts that you can and clean up the unit really well with some vinegar. You should probably also replace the whole magnetic shaft as well.
It might be easier to just buy a new proper pump. A Magdrive 12 would do nicely for your system.