We all know about seam rust, and rust in the front footwell but what about
seat belt rust?  My 91 Carat Vanagon rusted out right in the passenger side
door way.  Above the tire where the seat belt mounts to the floor, it rusted
away right there.  It seems that the mounting point of the seat belt is the
weak spot here.  They welded a nut into the body here and somehow the
undercoating was pierced by this nut (almost like it was added after the
undercoating).  This allows water, etc to get in around this nut and there
is also a seam where two sheets of metal come together.  It rusted at the
point where the nut was first then it started rusting down this seam.  You
have to pull up the piece of carpet that is above the wheel arch to see this
place but it would be worth taking a look.  The Driver's side seems fine so
maybe there was some defect from the factory that is just coming to the fore
front now.  I cut a piece from an 86 Syncro parts van to repair this place.
It was just starting to rust here as well (surface only).  You can check it
from underneath as well.  Look up at the bottom of the seat belt mounting
point.  You will see the nut there with undercoating surrounds it.  If you
see the undercoating peeling away from this nut then I would scrape it off
right there and inspect for rust.  

Thanks,
Ken Wilford
John 3:16
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