Rust....and Your Classic Car

April 22nd, 2015

Rust. Of all the four letter words you don’t want to hear, rust is the worst word possible when you are shopping for a classic car. Time and uncontrollable elements can take their toll on anything made of metal if not cared for properly and hidden away from Mother Nature.

Here is what you need to know about rust and what it means to your potential classic car. First, you have to realize there are different types of steel on your classic car and rust impacts each type differently. You can imagine that finished steel (having a protective coating) is more resistant to rust than unfinished steel, and that hardened steel is more resistant to rust than light stamped steel. You will also need to take into account the various rust stages.

Steel Types

  1. Stamped unfinished steel - These are light steel pieces such as seat tracks, seat springs, interior brackets and braces and some underbody pieces.
  2. Stamped finished steel - These are large steel pieces such as fenders, floor pans, rocker panels, pillars and roof.
  3. Hardened unfinished steel - These are very heavy steel components such as suspension control arms, sway bars, suspension springs, steering components, bumper mounts and drivetrain mounts.
  4. Hardened finished steel - These are structural steel parts such as frame rails and cross members.

Rust Stages

  1. Surface Rust - This is a light brownish discoloration, almost capable of being wiped right off and some rust removers will take this off easily. This is commonly found on stamped steel parts. This is not serious rust and its bark is worse than its bite in most cases. Rust has not yet pitted the metal itself. Depending on the type of metal surface rust is clinging it will take many years, if ever, to do real damage.
  2. Pitting Rust - This rust has been able to develop over time by extended periods of moisture on the metal. This rust has penetrated the pores and surface of the metal and some physical deterioration is present even though no rust hole has developed yet. The rust is able to be removed from the steel however the damage and deterioration remains visible on the metal.
  3. Panel Rot - This is the most damaging of all rust. The rust has been at work for quite some time and has managed to rust completely through the metal and holes are evident. This rust is pervasive and extensive. What may look like a very small hole, will turn out to be a much larger damaged area. This can mean cutting entire floor pans, fenders, and rocker panels off a car to properly repair it.

Many cars have inherent areas of rust probability that an experienced inspector would be keyed to inspect closely. While most cars will rust at the rocker panels, bottom fenders behind the wheels and floorboards, some cars have unique areas that are prone to rust. For example most GM cars such as Camaros, Firebirds, Chevelles and GTOs rust around the rear windshields badly. As well, a majority of Fords will rust badly in the front windshield cowls, shock towers and rear leaf spring areas. Mustangs are particularly prone to this.

Your first line of defense against rust when considering purchasing any classic car is a thorough pre-purchase inspection by a qualified classic car inspector who is trained and experienced with classic car rust issues and understands how significant rust can be to your investment.

©Road Ready Inspections, 2014