3-8
1997/98 Chevrolet Corvette
Collision Repair
Rail-Underbody Side Assembly
Sleeve
Fig.␣ 3.17 — Cut Sleeve to Make
L-Shaped Pieces
Minimum: 25 mm
Maximum: 50 mm
Fig.␣ 3.16 — Sleeved Butt-Joint
Sleeved Butt-Joint Repair
There are some areas on the rails that are best
repaired using the sleeved butt-joint method.
Use 25 to 50mm of material to act as a backing
plate when installing the sectioned service part
(Fig.␣ 3.16).
Notice: Use the sleeved butt-joint only in the
areas designated.
Notice: When determining the area to
perform sectioning near a riv-nut hole (within
the recommended areas), trim the sleeve back
3mm in the area for riv-nut clearance. The
riv-nuts are designed to crimp to one metal
thickness only.
1
Cut the service part to appropriate length
(according to dimensions), to replace
removed section of damaged rail.
2
From unused portion of service part;
measure, mark, and cut 25 to 50mm of rail to
be used as a sleeve (backing plate), at the
sectioning joint.
3
Cut through each side of the sleeve to create
four individual “L” shaped pieces that can be
installed in the undamaged portion of the
frame rail (Fig.␣ 3.17).
4
Install the four pieces, one at a time, and trim
them as necessary to provide a flush fit along
the butt-joint surface. Tack-weld the sleeves
into place.
5
Once the sleeves are in place, check the fit of
the service part. Grind sleeve as necessary to
allow for accurate alignment of the new part.
Notice: Retain a gap of one and one half
times the metal thickness at the butt-joint
when attaching the service part to the
vehicle.
6
Temporarily remove service part and prep all
bare metal surfaces with a suitable
weld-through primer.
7
Stitch weld along the entire sectioning joint.
Make 50mm (2inch) welds on all four sides of
the rail. Re-check the rails for proper
dimensions. Then go back and complete the
stitch weld. This will create a solid joint with
minimal heat distortion.
8
Clean and prepare all bonding surfaces as
necessary.
(Refer to SMC Repair Procedures.)
Important: Prior to refinishing, refer to
GM P/N 4901 Refinish Manual for
recommended products.
9
Apply approved anti-corrosion primer.
Notice: DO NOT top-coat any bonding
surface.
Offset Lap Joint Repair
The offset lap-joint is used in areas that have
extra internal bracing that won’t allow the service
part to fit properly with an internal sleeve. In
these areas use the offset overlap method which
will provide for some adjustment as well as allow
for cut lines that may not be completely straight
(Fig.␣ 3.18).
Notice: Use the offset lap-joint only in the
recommended areas.
1
Determine the location to perform the
sectioning
(be sure to stay within the
recommended areas), and cut the damaged
rail accordingly.
2
Cut any additional welds as necessary and
remove the damaged portion of the frame
rail.