So after some investigation the noise problem has been solved. Turns out that one of the three bolts holding the motor to the drive assy frame was missing and the other two were very loose. BMW does not sell the bolts seperately they are a part of the drive assy. Had one laying around that would work so installed in missing hole, tightened other two and voila all noise is gone. Silent operation. The noise was caused by the slop in the wiper drive assy. Replaced the blades at the same time figured they were worn from banging around either side of the windscreen...hope this helps someone who may have similar symptons....
getbmwpartsdotcom
j

__________________
Nobody... nobody trusts anybody now, and we're all very tired... there's nothing more I can do, just wait... RJ MacReady, helicopter pilot, US outpost #31.