Thank you for your answers
Shift+Ctrl+E fixed it indeed. I was not aware of this clipping issue.
My Model is centered at the origin ; I have some other object at some distance away from the origin, but not so far (about the main object size). I did not import from another CAD system.
Purging/fixing the model did not improve the situation.
Component axes are fairly normal, except for 90° rotation. Z-axis is aligned with the main Z.
I found out that clipping was coming back when using a Scene where the camera was positionned inside the model (close to the origin).
I guess that is the primary reason ?