yup try running it in water

 

yup try running it in water

Sounds silly, but that is a good question. Did you test it under water? If not you will definitely hear a loud clacking as the impeller vibrates against the shaft wall.

If it was making that noise under water, I would consider returning it. No telling what may be partially damaged or defected and if new, not worth the hassle of trying to fix.

 

My mag pump is quiet actually. I'm wondering if there's something rattling around in it that shouldn't be. I wouldn't run it and contact the seller. Hope they can help.

 

correction: sounds like a freight train out of water, but still pretty noisy in water. But it seems to pump pretty strong.

 

I have owned mag pumps. The 7 , 12, and 18. All were silent and reliable. Check impeller to make sure not broken. Also could be vibration in sump try putting felt or foam underneath. Will drastically reduce sound. If dirty may need vinegar water bath. Hope that helps.