How to Repair Rust Inside Car Doors

Metal and wet or humid weather don't mix. Surface rust repair is not a big deal and can be easily repaired. Trying to repair rust inside car doors is harder to do. Rust that starts from the inside is hard to repair and hard to prevent. Learn how to repair rust inside car doors to get your car looking new again.

Instructions

1. Assess the damage to the door in the rusted area. If the rust is just on the surface, repairs can be easily done. If the metal looks thick in areas, it means that rust is forming from the inside, slowly working it's way out.

2. Remove the door from the car to repair large areas. It is possible to repair the door on the car but is much harder. Remove the door and lay it on a soft surface, such as a blanket on a table, so the door doesn't get scratched.

3. Remove the door panel from the door by popping the plastic clips out and unscrewing any screws. Peel the plastic sheet off of the door behind the door panel to access the inside of the door. Several large holes in the door should allow good access to the inside of the bottom of the door.

4. Clean the inside of the door with a water-based cleaner. Use a spray bottle or garden sprayer to get down inside the door. Make sure all of the drain holes are open so the cleaner can escape.

5. Apply a rust inhibitor to the inside of the door after the cleaner has been removed and the area has dried. Spray the rust inhibitor inside the door, allow to dry and apply a clear coat of paint to seal the area. This should stop rust from forming in the future.

6. Sand down the rust on the outside of the car door with a rough grit sandpaper. Sand until there is no more visible rust. If the area is now uneven, a thin coat of putty can be applied (available at any automotive store). Allow the putty to dry. Use a fine grit sandpaper to smooth the putty even with the surface of the car.

7. Spray the sanded area with primer, paint and a clear coat. Follow all directions on the primer and paint. To get the correct color paint for your car, get the paint code off the inside of the door jamb, inside the glove box or from the manufacturer. Any paint store can follow the code to create matching paint.