Rust not only looks disgusting on any car, but also dramatically depreciates the vehicle’s resale value. So whether you are going to buy a used car or you simply want to protect your own vehicle, you need to know what causes corrosion in the first place, which parts of the car it ‘likes’ the most and how to combat it.
What causes corrosion?
Rust appears on a car’s bodywork wherever the car’s paint gets damaged. The damage can come from chips, bumps, scratches and crashes. It forms a tiny nick in the paint which exposes bare metal which reacts with water and the air over time creating rust. In the same way, wear and tear to the undercarriage of the car can also cause rust. Once the rust appears, it cannot be removed totally or stopped, but only slowed down. This is why it’s crucial to address it as soon as possible to minimise the damage to your car. You cannot practically protect your car from this sort of damage, but you can prevent the rust from spreading.
What car parts are the most vulnerable to rust?
Rust usually starts from the wheel arches and fenders and the car’s front is also vulnerable as it is exposed to stones flying from other vehicles. The edges of doors are also a prime spot for rust as they can be damaged on opening. The exhaust, radiator and suspension are common areas of the undercarriage and engine that can be damaged by rust.
Inspecting The Wheel Arch
If you are inspecting a used car, use your flashlight to check the area under the car behind all four tyres. Then look inside the wheel arches and into the wheel wells. What you are looking for is excess body filler – putty that hardened and feels like it is curdled. If you can see it and feel it with your fingers, then a corrosion repair job was done in this place. You need to find out how far the filler goes. Make a simple sound test. Lightly tap all around the suspected area. In the place where a metal sound changes for a dull, dense sound, the filler starts. A magnet will also help you to find out where the ‘healthy’ metal ends; it won’t stick to filler.
How to prevent corrosion?
The best way to combat rust is to prevent it from appearing.
To protect the engine – Lubricants such as motor oil or solvent refined oil not only reduce friction by separating moving parts but also protect these parts from corrosion. Not all oils are the same and it is important to use the correct oil for your cars make and model. There are online tools which tell you which is the right oil for your car.
To protect the bodywork – You need to regularly check your vehicle body for nicks and chips in the above-mentioned areas. Once you find a chip with some rust on its surface, sand it down using a sand paper. For a nick covered with rust, apply a piece of sand paper to a tip of a screwdriver and work up it. Then clean the area, let it dry, and accurately apply the touch-up paint. You can buy touch up paint from car parts warehouses and online. Sellers should publish lists of car makes, models and paint colours so you can get an exact match.
To protect the undercarriage – Another good thing you can do to your car to prevent rust is to periodically wash the undercarriage. When dirt builds up underneath the car, it accumulates some moisture and promotes corrosion. Clean surfaces dry up faster and are less prone to rust.