How do I restore my running boards?
I have a 1937 Packard 120 touring sedan and am wondering how to go about restoring its running boards. They are checked, dried and rotten, and chunks are coming out of them. I am told that replacement rubber is available, but I have not found a source. Also, can you tell me how to put on the new rubber? Is it doable by an amateur or is it best left to professionals?
It is possible and actually fairly easy to replace the running board rubber mats on your car at home. If you are shooting for show-winning concours d’ elegance perfection you may want to spring for the cost of a professional service, but you can do a perfectly presentable job yourself at home with a little patience and care. I suggest you begin by ordering the rubber mat for your car from Steele Rubber Products.
Start by removing the running boards from the car. You will need to remove all of the old vulcanized-on rubber, and to do that you will need a propane torch and a sturdy putty knife. Heat the rubber from the underside with the propane torch enough to soften and relax the rubber, but don’t get it so hot that the rubber melts. As the rubber gets soft, scrape it off with the putty knife.
A wire wheel chucked into an electric drill is good for getting the rest of the rubber bits off, and then you can go over the entire top surface with 80-grit sandpaper to remove any further residue.
It would also be wise to strip the undersides of the running boards too, and then remove any rust and make repairs. After that you can have them powder coated on the underside only or just prime them and shoot on black Rust-Oleum. I have found their products to be resilient and effective for years.
Do not paint or powder coat the top of the running board metal though. That’s because the glue you will be using will only stick to the paint if you do, and the chemicals in the glue will damage ordinary paint and powder coating. Instead, you can bead blast them or sand them down to clean rustfree metal and then coat them with 3M Single Step Primer. This will need at least 10 minutes to dry at 75 degrees ambient temperature before going further.
To install the rubber matting, use 3M Windshield Adhesive. Depending on the size of your running board, you will most likely need two tubes of the stuff. You can get it at automotive glass shops. You will also need a half-dozen of those spring-loaded clamps available at tool and hardware stores, plus four wood strips that are as long as your running boards and a couple of inches wide and a half-inch thick. You will want lacquer thinner and rags as well.
Before you start gluing, place the rubber mat on the running board and position it carefully so you can see how it goes and how it feels to handle the rubber. I say that because there are no second chances with this stuff. I use the urethane windshield adhesive because it is very strong and durable, but once it sets up, it is there for good.
Thoroughly wipe down the back of the rubber matting to remove any residue of the mold release agent. After that, rough up the gluing surface of the rubber with 80-grit dry sandpaper, and wipe it down again to remove any grit or dust. Finally, if it is a nice warm sunny day, put the rubber out in the sun for an hour or so to warm it up and help it get soft and pliable. If that is not possible, you can lay them over the hood of a car with a warm engine.
Start gluing along the outer edge of the running board. Keep in mind that you only have 10 to 15 minutes to make any adjustments. Press on the rubber, making sure it is positioned properly at the corners, and then smooth it into place from the center out to the corners. Use clamps and a board to apply pressure evenly across the surface.
Smooth on a thin layer of more cement and then pull the rubber over, pressing it into place holding your hands flat, and working out any bubbles. Attach more clamps and wood as you go. Keep going in this manner until the entire running board is covered. Scrape off any excess adhesive. Let the whole thing cure for a day or two before attaching the running board to the car.
If the running board rubber needs to be bent over at the ends, let it cure for a day or so, and then cement the ends into place. Finally, I have had good results for the last 30 years wiping down my cars’ running boards with Armor All periodically whenever I detail the cars. I shoot on a healthy amount and let it soak in for a minute or two, and then wipe it off.
The company that sells running board rubber mats for your car, as well as nearly every other rubber component you might need for your restoration is: