Model disappears when rotated in 3D

posted this in Microstation by mistake

My model appears correctly in plan and elevations, but disappears after a few degrees of a 3D rotation. 

As it disappears, the accudraw coordinates jump from normal numbers (<100') to numbers in the millions, (8 or 9 digits, positive or negative.)  

The camera can be on or off, still happens. 

Front and Back clipping planes are off.  This behavior persists across two different workstations, and also occurs in a file referencing this model.

Any thoughts?

dmg

CE u3