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2000 S-10 Blazer Door Rust

I just noticed rust on the bottom of my driver’s side front door. The rust is on the back of the door where the door skin is crimped to the door frame and has reached the bottom edge of the door. There is no rust on the other doors. The Blazer had been in an accident before I bought it. The door had been repainted at the time.

I’m planning on removing the rust and applying POR15 ( http://www.por15.com/POR-15/productinfo/1GB/ ) on the bare metal. If there is damage on the outside of the door, I’ll touch it up with a rattle can. I used POR 15 a few years back on the battery tray and was satisfied with the results. I’m more interested in stopping/slowing down the rust than making the door perfect.

If anybody has any suggestions, I would appreciate hearing them. I have to mail order the POR 15 so if there are any substitutes I would like to know.

Thanks,

Ed B.

I use POR15 all the time. It works very well. As you probably remember: you won’t need very much either as it goes a long way. In case you forgot, do wear gloves. Once it gets on your hands, it will take a good week to wear off.

Always remember the number one rule when it comes to rust on vehicles. The rust that you see is only 30% of the total amount of rust that there actually is in that area.

Tester

What he^ said.

Btw, if the inside of the door is in rough shape as well, I’ve had really good success putting POR in a cheap garden sprayer and hosing inside panels and other areas you can’t reach down with it. It can be messy and you will have to toss the sprayer out when you’re done but it gets the stuff where you need it.

Take the door panel off and take a look. I’m betting the bottom is pretty well rusted up. I’d put the POR15 on the inside too. Its a good coating but still isn’t going to stop the rust, just coat it. Eventually you’ll need to replace the door, weld in new bottoms, or coat or fiberglass it again for cosmetics so don’t be disappointed. My experience with it is that you want to mist a coat of primer on it while its still tacky. That’ll give paint something to bite into. Otherwise its too slick and paint doesn’t like to stick to it.

I’d bet that you have more rust inside of the panel than visible. Your treatment might be ok but I don’t believe you’ll eliminate the rust. If it were my vehicle I would tale off the inner door panel and mist the inside bottom of the compartment with used motor oil, then hit the outside where the rust is visible. If seeing the rust bothers you, sand the rusty part first and rattle can it, let it dry and then mist the inside with oil. Make this oil misting part of your maintenance (like when you change your oil). It might take you 5 minutes, do it while you’re waiting for your oil to drain on your oil change. Rocketman

In lieu of oil, there’s something called Fluidfilm that creates a tacky moisture barrier without the motor oil smell. It can be a bit messy because it never dries.
You don’t want it on anything that will get touched but I’ve used it on certain inside panels.

Thanks for the advice. I will be sure to pull the door panel off and take a look. I have to order the POR 15 and will post back with the results.

I used the POR-15 Start Kit (Degreaser, Metal Prep, and POR-15) and was pretty happy with the results. I treated the bottom of the door and about 3/16" of the outer panel. The result is hardly noticeable. I will pull the door panel off and coat the inside of the door with POR 15 or FluidFilm when I have a chance.

Ed B.

I used the POR-15 Start Kit (Degreaser, Metal Prep, and POR-15) and was pretty happy with the results. I treated the bottom of the door and about 3/16" of the outer panel. The result is hardly noticeable. I will pull the door panel off and coat the inside of the door with POR 15 or FluidFilm when I have a chance.

Ed B.

It works quite well. A little can also goes a long way.
Should you ever need something a bit thicker, try RustBullet. It doesn’t go on smoothly like POR but it is a bit stronger for areas that may get hit with road debris. You can’t use it very well in places where you need to do bodywork that shows but it is an extremely good finish for things like wheel wells, frame or the underside of a car.

Just be aware that POR does interact with sun light. Eventually it will fade from black so you may want to spray a coat of paint over it.