Pontiac tempest 1968 Service Manual page 673

14-4 1968 P O N T I A C SERVICE M A N U A L
F i g . 14-3 Pontiac G r i l l e
GTO ENDURA FRONT BUMPER REPAIR
DESCRIPTION
The new GTO Endura front bumper represents an
extensive effort by stylists to design a bumper that
appears as an extension of the car itself, rather than
an add-on assembly.
In order to create this appearance, the bumper is
painted to match body color. It is constructed of a
resilient urethane closed-cell foam, bonded to a
steel base. The foam is primed and painted with an
elastomer-base material of equal resilience as the
foam base.
Selection of the base material and paint finish was
influenced by the need for a bumper that would ab­
sorb a reasonable amount of isolated impact and
recover its original shape. Such Impact is charac­
terized by the type that causes unsightly dimples and
dents in steel bumpers.
The new bumper material will withstand minor
impacts and the resultant damage such as occur in
parking lots by recovering its original shape. The
paint film responds to impact in a similar manner
without cracking or splitting. In addition, the paint
finish may be polished for removal of surface marks
as with an acrylic paint film. If, however, an area
of damage in the bumper does not recover its shape,
or the surface is gouged, a repair system has been
developed to restore the original shape and appear­
ance of the foam base material.
The repair sequence amounts to a filling operation
with a flexible epoxy resin. After curing, the patch
is dressed to conform to the surrounding contour.
The refinish operation includes application of a
glazing compound which, after drying, is sanded
smooth, followed by the color coats and clear top
coats. The application and refinishing methods em­
ployed with this material conform to generally known