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Passenger-side Quarter Panel Replacement

This time I'm replacing the passenger quarter panel. To bring you up to speed, both sides of the car suffered from rocker panel and rear fender lip rust and my original plan was to go with used quarter panels. This plan worked well on the driver side. But on the passenger side, the donor quarter panel wasn't quite solid enough. So I bit the bullet and bought a new one from a local dealer. I figure not many people have used both old and new quarter panels on one project and at the end of this update I'll try to summarize the pros and cons of both approaches. Well, are you ready? Let's dive in.

passenger quarter 01

Barry came over to help remove the original panel. Since we're sacrificing this piece, we didn't bother drilling out all of the spot welds. A cut-off wheel works much faster.

passenger quarter 02

Barry cuts throught trunk support. While he's doing this, I'm drilling out the spot welds around the window and door openings.

passenger quarter 03

We're just making cuts to get the panel off at this point. Later, I came back and removed the spot-welded sections that were tricky to get to; like the overlap under the trunk hinge mount.

passenger quarter 04

With the spot welds drilled out, I seperated the panel with a chisel. It's important to be patient when doing this. It's really easy to mangle things while wielding a big hammer.

passenger quarter 05

Separating the kink.

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After cutting all the metal and drilling dozens of spot welds, it's easy to forget the body sealer between the panel and the inner fender. A body saw is the easiest way to cut through this stuff.

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There's still a long way to go, but getting the old panel off feels like a real accomplishment.

quarter dissection 08

For now, I left the original latch plate on. Later, I decided to remove it and use the latch plate that comes with the new quarter panel. This is the only major difference between this quarter panel repair and the other side. With the used quarter panel, it made more sense to keep the original latch plate.

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I removed the C-pillar support. Later, I sandblasted, painted, and welded it back on.

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After removing what was left of the old quarter panel fender lip you can easily see the extent of the rust.

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Another view of the same area.

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Taking a break from the quarter panel, it was time prep the inner-fender section that I saved from the used quarter panel. Here I'm filling holes, left over from drilling out the spot welds, with a MIG welder. I'm holding a copper welding spoon (made from a piece of copper pipe) behind the hole. The MIG welds don't stick to copper, making it easier and faster to fill a bunch of holes.

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After filling the holes.

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Now I'm ready to cut the rusty fender section out. Here you can see the cut line.

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Cutting with a body saw.

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My son, Will, displays our prize.

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The repair section.

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It took a bunch of trial-and-error work to get the repair section to fit properly. This felt like one of the slowest parts of the project.

quarter dissection 08

Before I removed the quarter panel, one of the first things I did was temporarily weld in a couple pieces of square tube so that they were just touching the inside of the fender. They served as a guide to help me put the repair section in the correct location.

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I cut the repair section a bit too much on the small side. So here I'm patching in little extra metal.

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I removed the rest of the latch plate and made a clean cut midway up the window opening for the new quarter panel.

quarter dissection 08

Time to take a deep breath and cut into my expensive, new quarter panel. I made my cuts a centimeter or so on the "fat" side to make sure there would be enough metal to make a good fit.

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The fit of the new panel left something to be desired. You can see how the lower-front part of the window opening doesn't line up. I had to drill out a couple spot welds, bend the window sill up, and re-weld.

quarter dissection 08

The fit down at the bottom, where the quarter panel overlaps the rocker panel wasn't any better. I made a couple pie cuts and re-welded them to get this section to fit. Apologies, I forgot to take pictures of these two modifications.

quarter dissection 08

Just one more rusty part to repair before the new quarter panel can go on. This is where the inner-wheel arch meets the trunk floor. You can see that the trunk floor is a mess too. That'll be the next big project.

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A view from inside the trunk. The camera is where the gas tank would be.

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Out with the bad...

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I cut some donor material from this section; saved from the donor quarter panel.

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In with the good.

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There. That's much better.

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Drilling holes for the side trim. I know, it's fashionable to delete the belt line trim from a 2002. But since when have I ever been fashionable? Also, I'll spare you from the big hole-drilling marathon that followed. To sum it up: I drilled lots of holes (spaced about an inch-and-a-half to two inces) for plug welds. Trust me, it wasn't that exciting.

quarter dissection 08

I'm using 3-M Panel Bonding Adhesive here. This part is the trunk hinge mount. The silver-colored stuff is weld-through primer. I removed the factory primer wherever there were going to be welds.

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Adhesive on the fender lip. The adhesive is applied to roughed-up, bare metal. I used a popsicle stick to spread it around.

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And some adhesive here too.

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Both mating surfaces get a coat of adhesive. You'll notice this area looks a little cleaner now. I don't have any pictures to show you, but I wheeled the car out into the driveway, sand blasted the quarter panel area, and gave it a coat of PPG DP primer.

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More adhesive.

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And finally, the quarter panel goes on for good. I think I used every clamp I own. One thing this sequence doesn't show is how many times the quarter panel went on and off the car. Believe me, these things don't just fit by themselves.

quarter dissection 08

After giving the adhesive 24 hours to harden, I started welding. I began by tack welding the C pillar and then tackled all of the plug welds, being careful to skip around so I wouldn't put too much heat into the panel.

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The trunk support after welding.

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The last thing was to do some seam welding underneath the car. These are additional welds to help stiffen things up a bit more.

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Done!

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The door and the panel lined up pretty well.

So, what's better, used or new? My answer: It depends.

Used panels cost a lot less. You can get two used panels, including shipping, for less than the cost of one new panel. Used panels come with enough donor material to repair the fender lip. Used panels are also likely to fit better. However, used panels have to be stripped down, and this is time consuming. Used panels are likely to need some repairs, even if they look straight and free of rust. Square taillight donor panels have to be modified for a roundie. And finally, used quarter panels are a gamble. You may not be able to tell if they're usable until you've spent several hours working on them.

New panels are pretty much a risk-free deal; you know what you are getting. New panels save time. New panels have no rust. However, new panels are expensive. The presses that stamp new quarter panels aren't as accurate as they used to be, so it takes more work to make them fit. You'll still need to repair the inner fender, and this adds up to more money still.

I think the decision to go new or used probably comes down to this: Who is doing the work? If you're paying a professional body man hourly rates to do this job, it's probably going to cost less in the long run to use new parts. However, if you're on a budget and doing the work yourself, used parts are a lot more attractive. I found that both approaches give satisfactory results, so I don't think you have to make your choice based on quality.

Well, that's it for now. The next, and last, rust repair project is to replace the trunk floor and tail panel. I hope to start on it later this Fall.

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