Expanding Foam Stuff

Stuffed ( snipped-for-privacy@rse.non) gurgled happily, sounding much like they were saying :

Depends.

It's been used by manufacturers extensively to provide both corrosion protection and strengthening - but if it's the *wrong* "foam stuff", it could be worse than blocking the drain holes and filling with salt water...

If you're interested in the car, try and find out what "foam stuff" has been used - specifically, if it's open-cell (bad) or closed-cell (good).

Not good, but wouldn't make me walk away if I liked it otherwise.

My Alfa Sud's front underpinning were factory filled with the stuff. Evil job to weld it, but you get there in the end.

Closed cell is still bad - if it loses adhesion to the steel then you get a block of impermeable foam in the middle with a layer of trapped moisture against the steel.

I liked the price, I liked the amount of MOT (although how it passed with two crazing and splitting tyres and a hole next to the rear suspension mount I'll never know) and I like the cars in general. Wasn't too keen on the car itself, but that was mainly down to the bodge artistry it's suffered, and the prospect of getting all all sorted.

I hate welding with a passion! And more to the point, I'm currently welderless. I asked the seller on the phone if it was solid, and he said yes. And I suppose other than a badly fitted sill a couple of years ago, and that small hole, it is. But having read stories about the foam, I'm not sure it'll stay solid in the long run :(

Think I'm best off steering well clear to be honest, the replies here aren't changing my mind a great deal (which is good, because I need help keeping me from buying crappy sheds :)

Thinking of drain holes, there appeared to be silver gaffer tape covering them in the floors...

The car had a sticky patch of paint from "when I used removers on the roof a few weeks ago", a less than awe inspiring part respray, and a worn out gear change. I pretty much wlaked away there and then, but I couldn't quite make up my mind to just leave it be. So I am partially interested, but as the owner is unlikely to be able to answer the specifics of the foam I'm getting less and less interested. A shame, be a damned good car if a little knowledge hadn't been a dangerous thing to it :(

Thanks for the answers, I'll carry on the search and keep my fingers crossed it doesn't take me back there :)

Ummm and... the Sud had an impeccable reputation for rust resistance, didn't it?

What?

Oh yeh, right.

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Stuffed" saying something like:

From what I've seen of that technique, it's time to keep your money in your pocket. The foam often doesn't stick to the metal and merely encourages more rust by trapping moisture.

My Elf had the sills & cross-member filled with foam when I bought it. I discovered this when I replaced a rotten sill. When I came to do the other side, even after six weeks standing in the garage, around half a pint of water poured out from the foam when I got the sill off. You might as well stuff the sills with sponges! Steer clear.