I just purchased my first Bronco (1974) and I am planning my frame off restoration. Not to stock but a sit you back in the seat roadster. I am a ton of questions but I will ask one now. What is the primary reason for the rust issues on these vehicles? And I am some what OK with replacing the rust areas on mine with new panels except for the bed quarter panels. I am just starting to see rust in the seam and I won
Body Panel Rust
- Thread starter nido
- Start date
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Are you talking the seam between the rear quarters and the corner post or the upper and lower rear quarters? The rust gets up there from the tires kicking water up into the wheel well. There isn't that much protection to stop junk from getting up into them. The only way to completely eliminate that type of rust is to make sure those seams are completely sealed with silicone or a seam sealer. Until you get them cleaned up and blasted, you really won't know how bad it really is. Whether or not you have to replace the entire quarter, which it doesn't sound like you do, or to just have to clean the surface rust off and put something like POR-15 on it.
Seabronc
New member
The majority of rust problems are caused by either galvanic action or water soaked mud getting stuck in areas of the paneling.
Galvanic rust is created by the passing of currents through the panels because of a difference of electrical level between them or using the panel as a ground path for lights. It will usually start at a place where there is a spot weld and spread from there. The passing of current between them causes a gradual loss of electrons on one side to the other just like battery plates.
Contaminants like salt and mud stuck in areas also causes rust to start and progress. Ford had a very poor design for the mud guards in the rear wheel wells that caused mud and crap to be thrown up into the base of the door posts as well as areas of the rear quarter panel. That is where you will see a lot of rot starting on Broncos. Also unprotected areas that are not sealed like the frame will just rust because of moisture and contaminant exposure. Another way for rust to start and go undetected for a while is a painted surfaces that actually had rust before being painted and not properly treated ahead of time.
There are products on the market that can effectively seal rust and provide years of satisfaction if they are applied properly. In cases where rust is already serious you need to take drastic steps to stop it, such as cutting out the rusted metal and replacing it. In the case of seams, you need to determine if it is surface rust or metal that is starting to be eaten away. Sand blasting will work for removing surface rust but the surface needs to be immediately treated with a rust converter / preventer to seal and prevent further progress.
Good luck on your project. Here are a couple of products to consider
http://www.por15.com
http://www.rustbullet.com
http://www.hammerite-automotive.com/
Galvanic rust is created by the passing of currents through the panels because of a difference of electrical level between them or using the panel as a ground path for lights. It will usually start at a place where there is a spot weld and spread from there. The passing of current between them causes a gradual loss of electrons on one side to the other just like battery plates.
Contaminants like salt and mud stuck in areas also causes rust to start and progress. Ford had a very poor design for the mud guards in the rear wheel wells that caused mud and crap to be thrown up into the base of the door posts as well as areas of the rear quarter panel. That is where you will see a lot of rot starting on Broncos. Also unprotected areas that are not sealed like the frame will just rust because of moisture and contaminant exposure. Another way for rust to start and go undetected for a while is a painted surfaces that actually had rust before being painted and not properly treated ahead of time.
There are products on the market that can effectively seal rust and provide years of satisfaction if they are applied properly. In cases where rust is already serious you need to take drastic steps to stop it, such as cutting out the rusted metal and replacing it. In the case of seams, you need to determine if it is surface rust or metal that is starting to be eaten away. Sand blasting will work for removing surface rust but the surface needs to be immediately treated with a rust converter / preventer to seal and prevent further progress.
Good luck on your project. Here are a couple of products to consider
http://www.por15.com
http://www.rustbullet.com
http://www.hammerite-automotive.com/
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[-o< Thanks! I am sure after the body is off and on a rotisserie I will have a much better feel for the rust issues and why they happen. I found a link for replacing floor sections, do you know of a link that goes into detail about the replacement of the door post panels and rocker panels? Thanks
Rockers are all held on by spot welds. You can see them running along and can drill them out. Fairly easy to take off and put back on. Just be sure that if you have a spare tank behind there to drop it otherwise you will have a "breathable" gas tank. I have never done the striker or hinge post, but they are seperat from the body panels themselves. Again, once you get the thing media blasted, you will easily be able to see the seams and should be able to take a cut off wheel to them and zip them off fairly easily.
