Corvette V8-350 5.7L DOHC VIN J MFI (1990)
4.
Finish block sand areas with # 280 - # 320 dry sandpaper.
5.
It is recommended that the entire hardtop be repainted. See Chevrolet Dealer Service Bulletin No. 87-292-10 for paint specifications and
application.
Plastic Build-Up Technique
In some instances, the damaged area requires a plastic build-up to restore the original contour. When the fiberglass laminate is not pierced through or the
damage is not extensive, the repair is as follows:
1.
By sanding, remove paint down to the fiberglass laminate from the area surrounding the damage.
2.
Grind or file to form a "V" at the damaged area. The side of the "V" should have a pitch for maximum bonding surface.
3.
Scuff sand area surrounding damaged area to provide a good bonding surface.
4.
Clean work area with Sikkens M-600 cleaning solvent or equivalent. Use a tack rag for finish clean up.
IMPORTANT:
Cleanliness is very important. Be sure repair area is clean and free from dust and debris.
5.
Cut to proper size, buildup patches out of 1-1/2 ounce fiberglass mat.
6.
Mix polyester resin and hardener as indicated by the manufacturer.
IMPORTANT:
Remember, cleanliness is important. Mix the polyester in a clean container. Do NOT use waxed cups for mixing. Be sure to close resin and hardener
containers after use.
7.
Apply a layer of resin and then work in a fiberglass patch until the resin completely penetrates through the fibers.
8.
Continue to build up layers of fiberglass and resin until the surface is approximately 0.8 mm (1/32 inch) below the normal contour of the surface.
9.
Finish the last build-up with Sikkens Polystop LP or equivalent.
10.
Apply heat to repair area. Heat lamps are recommended to be used at least 300 mm (12 inches) away from the repair. Allow at least one hour
curing time. If heat lamps are unavailable, allow to cure at room temperature of 21 to 24 Celsius (70 to 75 Fahrenheit) for eight to ten hours.
11.
Finish the repair by grinding, sanding and cleaning in the usual manner.
12.
It is recommended that the entire hardtop be repainted. See Dealer Service Bulletin No. 87-292-10 for paint specification and application.
Structural Repairs
Damage to the hardtop such as cracks or holes that pass completely through the thickness of the fiberglass laminate and into the foam core are known as
structural damage. This type of damage can affect the strength and structural soundness of the laminate. All structural repairs require the use of fiberglass
patches to provide the mechanical strength needed to keep the repair structurally and visually intact during normal usage. The patch also provides the
required foundation to build and form the exterior surface to match the original contours. The following is recommended for these types of repairs:
IMPORTANT:
Any damage that fractures the hardtop through both layers of laminate and foam core substructure is to be considered non-repairable structural damage
and the hardtop should be replaced. Any damage that deforms the roll bar of steel reinforcements in the hardtop, even though there appears to be no
major fractures in the laminate, should be considered non-repairable damage and the hardtop should be replaced.
1.
Sand off finish from around the damaged area and inspect for cracks in the laminate.
2.
Remove all broken and fractured laminate and grind a "V" around the hole to provide maximum adhesion.
3.
Cut fiberglass patches to fit the opening.
4.
Clean area to be repaired with Sikkens M-600 or equivalent.
IMPORTANT:
Cleanliness is very important. Be sure that the repair area is clean and free from dust and debris.
