[niterydr]

It would fuck up the crank because....
The oil pump would pickup the metal/oil combo and evenly distribute it between the new bearings and the crank/rod surfaces.
Don't worry, it also sends the metal filled oil up to your head to coat your cams.
Usually a balance shaft failure just makes clunks, when it makes a metal/oil combo, the motor suffers. Good luck.
Its a bearing that went to the shitter. Start checking to see where it came from. Check your oil pump for excess run out now, check your rods, etc...