How is the trunk floor welded to the quarter panels.

[wim van wesemael]

Hi there, 

 

I've just started the repairs on my 02 touring. Being a touring body panels are ultra rare and I'm planning on fabricating as much as possible. 

 

The trunk floor or pretty much everything below the bumper line is rust. 

 

Parts of the floor at the back panel were being held together by bondo and fiberglass. Especially the seams near the rear panel. 

 

Around the fuel tank the damage is so bad I don't see how the edge of the floor panel is welded to the sides. As I'm trying to stick to factory look I'm looking for photos and info on how these panels attach. 

 

For now I can only find that the floor has an edge which touches the quarter panels. Is it welded in the seam? Spot welded through this edge onto the sides? 

 

 

[Mike Self]

I've not delved into a touring's innards, but on the sedans, the quarter panels aren't welded to the true (steel) trunk floor at all--at least not between the inner wheel arches and the rear body panel.  The gap is filled with seam sealer at the factory.  

 

mike

[wim van wesemael]

Well it doesn't *look* welded. But then how is it held in place? 

The whole rear is smudged by anything sealer like in existence from the last two decades.

It's nearly impossible to find any seam and I'm not keen on starting cutting without a plan. 

[02Les]

5 minutes ago, wim van wesemael said:

Well it doesn't *look* welded. But then how is it held in place? 

The whole rear is smudged by anything sealer like in existence from the last two decades.

It's nearly impossible to find any seam and I'm not keen on starting cutting without a plan. 

 

Hi,

 

I would contact (private message) D.martijn who is doing an in-depth restoration of his Touring.

 

 

[TobyB]

2 hours ago, wim van wesemael said:

Well it doesn't *look* welded. But then how is it held in place? 

The whole rear is smudged by anything sealer like in existence from the last two decades.

It's nearly impossible to find any seam and I'm not keen on starting cutting without a plan. 

 

Glue.

 

One of the earlier cases of 'panel bonding,' as Mike noted above.

 

It wasn't one of their better ideas in 1966, as the bond tended to collect

condensation and rust.

 

It got worse when the rear impact panels were bonded to the skin starting in 1974 for the US market.

 

t

 

something about flies and honey...

[wim van wesemael]

So in essence, when I figure out the panel puzzle, welding or spot welding these and sealing is an improvement... 

[Mike Self]

2 hours ago, wim van wesemael said:

So in essence, when I figure out the panel puzzle, welding or spot welding these and sealing is an improvement... 

If you try welding the trunk floor to the quarter panel sheet metal, you're not gonna be successful.  Clean out all that old seam sealer and you'll notice a 5-6mm gap between the quarter panel and the trunk floor.  Too much of a gap for welding.  

 

I think the reason that that sealed gap collected rust is that the factory put the sealer in place to close the gap before painting, so the metal under the sealer was bare.  I noticed that when I was doing some repairs on my '69's quarter panels.  I ended up digging all the old seam sealer out, then primering the raw metal on both panels with an anti-rust primer, squirting in new sealer and finally painting.  That was in 1998, and so far no more rust...

 

mike

[wim van wesemael]

9 hours ago, Mike Self said:

If you try welding the trunk floor to the quarter panel sheet metal, you're not gonna be successful.  Clean out all that old seam sealer and you'll notice a 5-6mm gap between the quarter panel and the trunk floor.  Too much of a gap for welding.  

It's mostly the edges that are gone. Weird enough the quarter panels are unaffected. 

So I'll need to fabricate this edge anyway. It would be weird to patch it up but then leave such a large gap?

[TobyB]

They did it that way to avoid distorting the outer surface of the rear quarter panel.  Welds would have

dimpled it, and continued to distort it as the trunk floor shifted.

 

It's a design failure- the loads from the trunk floor shouldn't be introduced to the middle of 

an exterior panel.  But this car was a last- ditch attempt to get something profitable out the

door, and it was designed to be limited- lifespan, so they glued it.

 

Like Mike, I have cleaned up the joint best I could, sealed the metal,

then used a more- modern panel sealant that's designed to cover gaps.

 

fwiw,

t

 

[wim van wesemael]

Allright! 

I didn't think about the panels warping or dimpling. It should be manageable though. 

I'm not going to to use it for hauling large loads anyway. 

 

So in general, the suggestion here is to keep the gap and still glue it. 

[Arizona02]

modern era cars are made using panel bond adhesive, 3M is one supplier.