Corvette Restoration Tip: Chassis
This Corvette Restoration Tip is brought to you by Zip Corvette and can be found in Zip’s free Corvette Parts & Accessories Catalogs – request one online today.
Everyone knows Corvette bodies are invulnerable to rust but the same is not true for the chassis. The fully boxed side rails and cross members in 1953-1962 models impart significant strength to the chassis but they are particularly susceptible to rust because water can get trapped inside.
1953-1962 Corvette
If the Corvette’s chassis has a rust problem it normally manifests itself in the rear most crossmember first. Other sections that are especially at risk include the side rails in the areas beneath the doors. Because the rot progresses from the inside out, a problem may not be apparent from visual inspection alone. Poke along the bottoms of the rear crossmember and side rails with a pick tool or tap these areas with a ball peen hammer to expose any weaknesses.
If you discover rust, the best solution is to replace the damaged sections with new reproduction pieces. For the side rails this means cutting out the rotted section slightly beyond the damaged area and welding in new sections. For the strongest repair, weld in an inner sleeve that bridges the seams between the new sections and the original frame.
Rather than repairing a Corvette rotted rear crossmember, it is preferable to replace it. The original crossmember is held on by a combination of rivets and welds and for the best result you should attach the reproduction crossmember in the same way.
Whether or not your chassis requires rust repair, you will want to strip and refinish it during a comprehensive restoration. There are various methods for removing paint, undercoating, rust, and other surface contaminants, including abrasive blasting, chemical stripping, and electro-chemical immersion. With electro-chemical immersion the chassis is placed in a large vat of liquid and subjected to an electric current. The chemical bath and current together completely strip the chassis inside and out. This is the most thorough method of stripping but it must be done by a specialty shop with the right equipment and requires that the inside of the chassis be coated as well as the outside to prevent future rust problems. Chemical stripping is effective but not recommended because it is very difficult to prevent the stripper from getting into the areas between overlapping metal. Abrasive blasting is the most popular stripping method because it’s relatively inexpensive and very effective. The coarse surface texture it leaves behind provides excellent grip for the new coatings you will apply, but it is important to thoroughly clean out all traces of the blast media to prevent it from clogging the chassis’ water drain holes.
For the ultimate in authenticity, refinish your chassis with the original asphalt based paint but for maximum durability and corrosion protection, use a two-part epoxy paint or have it powder coated. For the best of both worlds use epoxy primer and sealer undercoats with old-fashioned asphalt based topcoats.
Related posts:
How do I adjust or replace the trunk lid springs on my 1958 Corvette? The trunk lid does not stay up when I open it. It appears that the springs are too weak to keep it open.
Eric,
There is no adjustment, the springs lose their strength over time. Replacement is not easy, as they have to be compressed when installed.
Thanks for the help. You are right, replacing the springs can be a real pain. The best way to compress them is to lower the Corvette’s trunk lid as far as you can, crawl into the trunk, and wire them to keep them compressed.