Quarter Panel Seam -- Repair or Replace?

[Erich]

Hey ... I have a '77 that has rust in the usual places. I'm in the middle of replacing the floor pans, rockers, and door posts. I was hoping to stop there, but I am now wondering what to do about the rusty quarter panel seams.

The rust has pitted the metal and sort of "run down" the bottom panel for about 1 1/2 inch. I sanded a little and it does seem that there is some solid metal, but it hard to tell how thick it is.

I was thinking that a good spot media blasting, POR-15 and some lead filler would do the trick, but I don't want to see bubbles showing up a year after the paint goes on.

The tailgate posts and back seem to be OK. Ripping out and replacing both the top and bottom quarter panels seems to be a huge job -- especially messing with the gas doors on a '77.

Any thoughts and advice on what I might do?

Thanks from a newbie!

 

[Bully Bob]

I've cleaned out/up a couple of them & painted. Although, I didn't keep the rigs long enough to see if it held.

The key., I think, is to look close on the inside of the bed....if there's no early sign of rust coming thru., then patching would be warranted.

That area is doubled over with a membrane of sorts., as I recall. Seems there was plenty of metal to work with.

 

[Lyle]

I had my seams media blasted then applied 'panel bond' material to seams. This is a high tech meterial used in newer vehicles to "bond" steel panels together. It is stronger than the original metal and when applied does not distort metal as welding will do. It filled the slight pitting that remained from the surface rusting after the media blasting. It is a two part compound that is mixed as it is being applied by the applicator gun (similar to a caulk gun). Once sanded, primered and painted along with the rest of my 77 it looks great and has held up very well for over two years now with no signs of repair or failure. It is available from your body supply house. My 77 has only 29 thousand original miles but rust was evident much like you describe yours as having. All other rust areas were replaced with new metal. Good luck with your Bronco, it may seem like a lot of work now, but it will all be worth it later when you are close to being finished (notice I did not say "when you are finished". I don't know if one is ever "finished" with an E.B.).

 

[68rrflyer]

If the panels are solid and you don't see any rust coming through, you may have a few options. I would use a heavy duty stripper wheel, like the one 3M makes, and go over the metal. If it eats through the panel then the rust was only a few months away from breaking through anyway. Then you can patch after you cut it out. If all's well after a rough sanding or spot media blasting, I would then use a rust neutralizer such as Eastwood's fast etch. Basically, a rust eater that you then neutralize with cleaner. Since you have some pitting, I'd then use a quality fill like USC's All Metal to fill in the pitts. Expensive, but good stuff. It's not "bondo" and I'd stay away from the POR-15 in your case. The All Metal is what I use on gaps on my other 60's cars for quarter panel to roof and quarter panel to rocker seams that were normally leaded from the factory. After all that spray it with epoxy primer and you're good to go for final bodywork when the time comes. Good luck! B)