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Dr. Flyview
05-28-2006, 05:24 PM
Hi,

The e36 I'm looking at has some rust at the opening edge of the trunk and a bit on the metal below the opening of the trunk. It also has a bit on the side spoiler and a few very minor very shallow blotches on the hood.

Is it fixable? My dad said the mechanic said rust always comes back even if you fix it.

dave328i
05-28-2006, 05:29 PM
you have to grind it out, so that it's just good metal, and no rust remains...

if you just cover it up with bondo, or try to paint over it, it will come back.

Justin e36
05-28-2006, 05:29 PM
If fixed properly, it will not come back.

WhadUpp
05-28-2006, 05:36 PM
replacing/welding new panels are the surest way to do away with the rust.

KaschmirBeige3
05-28-2006, 05:38 PM
Like the others above mentioned if it's fixed properly it won't come back.

Dr. Flyview
05-28-2006, 05:42 PM
Cool...how much could this cost me? I could replace the trunk but what about the rusting underneath the trunk? You replace the whole bum of the car?

P.S. goddamn Kaschmir I love your girl.

Justin e36
05-28-2006, 07:48 PM
Unfortunately the piece between the trunk and rear bumper can not be replaced easily, as it's a part of the unibody design of BMW's. There are two visible weld points under each tail light, you'd have to cut out the whole rear section and replace it.

spooner_dee
05-28-2006, 08:48 PM
Unfortunately the piece between the trunk and rear bumper can not be replaced easily, as it's a part of the unibody design of BMW's. There are two visible weld points under each tail light, you'd have to cut out the whole rear section and replace it.


not trying to thread jack, but that piece on my car is kinda bent down (most likely rear ender b4 i bought it, can that be pulled back in place by a good shop, or just have it cut and replaced?

Justin e36
05-28-2006, 08:49 PM
It can be pulled out then bondo'd smooth.

dtthiaga
05-29-2006, 08:30 AM
It is hard to fix, but can be done.

My old 97 e36 had rust forming big time on the bottom lip, where it meets the bumper. BMW fixed it under warranty, and within 2 months, the rust was back. They did a poor job of grinding. My door seams started rusting as well, but I didn’t bother fixing it (sold the car).

I've fixed rust spots (but never at a seam or lip with success) by grinding it down carefully.

You have to get out the little black pits (rust) as well. I use a highspeed dermal with a grinding wheel to remove every last bit of rust and pits in a controlled manor. 1-2 years and no rust. I wish I took some pictures of the steps….

Dr. Flyview
05-29-2006, 09:55 AM
What do you do once you grind it away? How do you fill it back in?:confused:

BennyL
05-29-2006, 10:03 AM
ok, my question is related, but slightly different.

if you have some rust on a certain area of the car - lets say the rear fender, for example - and you have it grinded down properly and everything, then comes time to repaint it (obviously). so, my question is: do you have to repaint the whole panel, or just the area where you were sanding. in other words, would the whole rear fender need to be resprayed, or just the area where the rust was?

spooner_dee
05-29-2006, 10:16 AM
ok, my question is related, but slightly different.

if you have some rust on a certain area of the car - lets say the rear fender, for example - and you have it grinded down properly and everything, then comes time to repaint it (obviously). so, my question is: do you have to repaint the whole panel, or just the area where you were sanding. in other words, would the whole rear fender need to be resprayed, or just the area where the rust was?

comming from an auto body past, when ever repainting any part of the car, it is best to do the whole fender as well as in your case the trunk and maybe door.

this helps in matching. if you paint just one spot, everyone will see and know, its best to over lap over a few touching panels that way its harder to tell that its been resprayed. no matter how good a shop is, the paint will never match 100% do to age wear and just not mixing it perfect.

Darkness95m3
05-29-2006, 04:24 PM
Anything is fixable, just depends on the cost and materials used.

propr'one
05-29-2006, 05:41 PM
Anything is fixable, just depends on the cost and materials used.
Well put. The trunk lid on e36's is notorious for rust. (my car is currently at the shop having the trunk resprayed for the same reason)

IMO, the metal used on bmw's is good, and thick enough to be grinded down well and repainted. However, that is relative to the rust damage. If there is ever a hole in a panel, i'd always say replace it. If its just surface rust, have a good shop give you advice, i say grind it down and paint it:)

dtthiaga
05-29-2006, 07:40 PM
For small areas, I've grinded it out and painted it myself. It's not 100%... but 90-95%.

I posted my latest fix over the weekend; it is more of a paint repair, but the steps would be the same. The only difference would be the rust prep steps before: the grinding, primer, bit of putty, sanding, primer, then to the paint.

http://www.maxbimmer.com/forums/showthread.php?t=72293

Caution, the repair area I did was larger than my liking. I would have liked it to be smaller, but the paint was damaged already.

I have one rust spot on a door edge on the commuter car that I want to fix. I’ll try to take some DIY pictures if I’m not too lazy.

Oh, the info is just from experience. I’m not a body guy… engineer. :)