Hello 1116713,

You may want to remove the 315415710 spindle head, and inspect the bearings inside to see if they are not defective. Also check the 341160960 spindle to see if the bearings are tight on the spindle. Look at the 339038180 ring, and make sure it is not loose in the housing also.

Hope this helps,
-WJA

Thanks for the reply.

I did check the spindle head and all looks ok.

I think the problem is here Field Coil 120V
Part Number: 311009760. It is a bit loose inside. This is the part holding it ( spindle side ) Baffle
Part Number: 339150880. I wonder if there's something wrong with it. I did place 2 O rings on each leg end so it can push/ hold the Field Coil better. Seems to be working OK now as noise is gone even when I trun the grinder around. I'm just not happy that it needs to be done on a brand new grinder. Is there something else I'm missing here. Will replacing Baffle
Part Number: 339150880 solve the problem without the need to add O rings. tks