Phrase you'll never hear: The rust isn't as bad as I thought

jefflit

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Despite being an original blue plate California car, my 73 has some rust. I knew the spare tire well and the right rear pan were rusty so I bought a replacement right-rear floorpan panel from Mike P. but after lifting the carpet I find it is worse that I anticipated. While the pans under the rear seats are bone dry, the rust extends up to where the floor pan connects to those pans (item #1 in the W&N diagram at https://www.wallothnesch.com/en/karosserie-blechteile/bmw-2-5-cs-3-0-csl-e9/katalogbild-41-05.html which doesn't seem to be available), giving me nothing to weld to. It looks like the original floor pan curved up but the replacement pan is flat. Seems like a hard part to fabricate as it has a curve and a number of indentations. Any thoughts?

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Thankfully, the rear seat portion and rear subframe mount area are pristine.
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When I bought the car I didn't realize it had any rust in the front pan but after really getting under there I found that the A/C condensation and exhaust heat caused a hole above the exhaust. Seemed workable. Then I removed the carpet and found a big hole around the plug above the frame rail that was not visible from below. Annoyingly, also a small hole up higher near the tunnel, probably above where a floor pan patch panel will reach. Surprisingly, the rest of the floor pan is bone dry, including the lowest part where the big circular drain plug resides. No real question there, just more work. Sigh.

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These E9s are such crap shoots.

Looks great from the outside, but these cars all seem to get rust in the most unusual, difficult places.

$50k car looks great, but dig some more and now you have $30k in body/paint work to do.
 
A good metalsmith can easily make and form patch panels and modify the W/N panels to fit like a glove and make the car like new. Modern etching primers and seam sealers will make the car much more protected than when the car was built. Rust abatement is worth paying someone to do.

Have a friend who's CS lived in Southern New Mexico all its' life. It had rusted floors that had to be cut out and repaired too.
 
I was told that Mike Pelly's pans were the best, and they may be, especially for the front, but in my case I think the W&N rear floorpan will be a better choice because it includes that area I was concerned about. Compare:
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In this case the W&N panel seems to include that rise that I need. Note that Mike's latest rear pan includes more material towards the sill side, with a lip bent in. Not shown in that picture above.

However, neither front panel seems great for my application. The W&N is basically flat with the recess I don't need. Mike's looks much better but has different ribs and indentations than the original pan in my car. Compare:
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The foot well looks to be half decent condition ... can the rot be cut out and new small sections let in , you will not need to spend money to buy the W'N pan - and will save you come cash... I wish my car had that little rust!
 
The W&N panels indeed would be your best for the rears; they have the ridges and indentations you're looking for.

I personally liked the W&N rear pans, although they are 10 mm short in some dimensions, and the spacing of the ribs is off by a few mm's. Depending on how nerdy you on originality, you might want to redo parts of the W& N panels.
The fronts of W&N indeed miss some details that are present in Mike Pelly's pans. I made simple press tools for these details with an angle grinder, drill and router and use M12 bolts to do the pressing; it's thin steel. Pelly's front floor isn't fully correct either; the front lip is kinked where it should be bent, and the flange should continue following the radius up to the firewall.
The link that Keshav posted to the Pelny panels (Poland indeed; http://sklep.manufaktura-workshop.pl/index.php/czesci/bmw/) shows front panel that has all the details; they look to be superior over W&N & KMike Pelly's, not sure about measurements as I haven't seen nor used them. I would have bought those if they were available when I started.

There are comparisons of replacement panels in various threads on this site. I wrote more details there, with pictures.

Besides the rust holes that you see, you'll have to factor in that likely rust hides in the seams as well; where the floor meets the inner sill and where the floor is strengthened under the seat. The pic of the rear subframe mounting point is generally the right area to look at, but from the inside your looking at the robust thick metal bracket. that side hardly ever rusts. It's the underside and the seam to the rear wheel well that gets eaten first and thus the first point of inspection.

It's crawling time...
 
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From the guys in Poland?

I think so, possibly the German seller who is an avid E9 guy and has other E9 parts too for sale, has ‘hooked up’ with the Polish guys....... and markets them in Germany.
 
Wow- muy rapido!
Gracias

I’m pretty certain that I may just repair the holes in my hat shelf. Having just removed one, I can honestly say that spot weld access is a little challenging. The tack welds along the fender wells aren’t too bad but it also gets tight up near the c-pillar. As you can see, I kept the rear windscreen frame intact (on purpose).

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Thanks for the info. Here's a short update...

The good new sis that, after crawling around and scraping off some insulation, the car truly is dry under the rear seat area and everywhere except the right side floor pans.
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Having determined that the right rear floor pan rust was worse than originally thought, I purchased the replacement panel from W&N. As you can see from the photos, it has a lot more of the original contours needed for my application than Mike's piece.

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That said, it ain't perfect. As others have already noted, the spacing between the ribs does not accurately align with the ribs in the car. You can align one rib but then the subsequent ones get progressively further away from where they should be. Not sure if this is due to variations in the original floors over the years or just an inaccurate repop. Either way, it makes the job a LOT more difficult. Sigh.

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I'll struggle to make it work. Then I need to move on to the front. It would seem that the Polish panel was the most accurate but the front panel images are now missing from their site and I've heard that they aren't being responsive to orders? Anyone have experience purchasing from them?
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Also interested on how people have finding the panels from Poland. Getting closer and closer to ordering the repair panels for mine
 
I'm using the W&N rear floor pans as I think the pressing is better than the Polish panel, also the W&N panel has the rear stabiliser mounting nuts already welded in place.
Using the Polish front floor pans as they have all the swaging and pressings for all the holes, but have found most of them are 10mm out of line. So I have had to cut and re-weld the panel to get all pressing to be in the right place.
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I’m very close to pulling the trigger on floor
pans also. I am heads down in TIG welder research at the moment.
 
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