Best preventative maintenance/ upgrade you can perform on your Porsche, even more important than that new strut tower brace or shift knob: Replace all the rubber seals.

http://www.pelicanparts.com/catalog/...911_seals4.jpg
http://www.pelicanparts.com/catalog/...911_seals2.jpg

good question. I think it says Porsche or something like "genuine Porsche". I may be wrong but I don't think OEM are the correct ones in this case.

That's part of why I plan to glue in my windshield. I don't plan on doing rust repairs on this thing again. :)

Since you've spent a lot of timing looking at rust, can you make list of the top places one should look for rust when inspecting a car for sale?

People will tell you that surface rust is surface rust. Its your money. I personally see it as the tip of the iceberg on these cars rather than a starting point it is often the end of long rotting process going on from the inside out. All of it can be fixed though.

Most of what I have seen I think I can attribute not as much to outside elements attacking the outside but those elements getting inside and going to work (thus the reason for this thread).

1. Paint bubble on rear between glass and decklid = parcel tray

2. Surface rust inside the door where the lock post and rocker panel meet = kidney bowls and inner rockers (or at least rocker ends) plus rear subframe section (ends of torsion tube).

3. Visible rust behind the dash where it meets the A pillar = windshield cowl and corner. Also suspect the entire front door post rotting from the inside out.

4. Paint bubble near the corner of the front cowl ahead of windshield, suspect dash and A pillar/windshield track. (if lower corners of glass are foggy, definitely windshield track although may be minor).

5. Surface rust in battery area in the trunk = front suspension pan (remember what I said about surface rust).

6. inside, lift the carpet at the front of the seat base. check out the vertical area below and beside the seat. If its bad, maybe also need floor pans and rear seat base. If it is really bad suspect rear torsion tube as well.

7. Underside, check floor, torsion tube, rear subframe section (ends of torsion tube) and also suspension pan.

8. back inside, lift carpets and check pedal box area as well as the frontmost area of the floor near the rocker panel and wheel well (where your left foot goes)

These cars rot in different areas than many other cars. Often door seems are good, rear fenders are good but chassis is rotten.

Normal areas to check as with other cars are bottom of door seems, headlight buckets and front fender doglegs.

There can be rust in other places but if you don't find it in these spots first, the other areas are likely ok. 72 and 73 had galvanized lower bodies I am much more wary of a 1969 for instance. The galvanized ones still rot badly, but much more slowly than older cars. I've also seen 993s with the cowl bubble, and 964s with rotted fender top mounting areas. When people say later cars are galvanized so don't worry, don't dismiss rust, it still happens on those cars and can be bad, just takes much longer to get out of control, but SC suspension pans are certainly not immune. i've seen enough of them to know.

Check out my build thread. I've indexed it on one of my later pages and linked to other threads with more info.

How hard is it to lift the carpet?
Do you need to unbolt the seats or door sills?

Most sellers might not want a stranger taking a wrench to their cream puff.

The seller has three options:

1 send you on your way

2 allow you to assume the worst and negotiate accordingly

3 allow an inspection. Having it done at a reputable shop is not unreasonable

P.S.
That's why I bought the car I did. It was already apart

Don't worry, its galvanized?????
 

I have been bothered by advice that keeps popping up on this board relating to rust.

For over ten years people have been advising to just buy a later galvanized car and not worry about rust (Or buy a 3.2 and not worry about transmission problems with a G50).

Maybe ten years ago that advice had some merit, but all of these cars are getting old and I have even seen 993s with the same telltale cowl rust that early cars develop when the windshield seals start to leak.

As evidence, a member just posted a picture of a 1987 model.

When you look at this picture, remember that this car is of the galvanized era...

http://forums.pelicanparts.com/uploa...1393209089.jpg

This car looks like it is rusting form the bottom up. As some state in the OP, likely sat in saltwater. Obviously even a galvanized car will rust from that. Hell, I am pretty sure a stainless steel car would too. Anyone here ever give a DeLorean a saltwater bath? ; )

No, it didn't sit in salt water. It got used in the rain. Lots of it.

That's the point of this thread. There are a bunch of places that water will collect in a 911 body shell if it gets wet. This is made worse when seals fail, rubber gets old, damage is not corrected, etc. Get it wet often enough and it will rust.

Porsche expected its cars to get more servicing than is typically done. I don't mean oil changes but thorough inspections. All the little things that the typical owner ignores completely... They had some long warranties agaist rust perforation but they required that you do an annual (or bi-annual, I don't recall) inspection of the underside of the car and correct any issues.

That still won't solve the rust issues in certain places, as some of that can't be seen without disassembly. They all rust, some sooner than others.

JR

My '87 had the very beginnings of rust in the LH side of the windshield cowl. Mine was a result of a crappy windshield replacement where the new glass was used with the old seal/gasket. Just a tiny bit of rust on the pinch weld and down in the valley of cowl. My local buddy Souk's '89 Fat Bastard had considerable rust in that same cowl area. In hindsight it would seem to me that Porsche should have put a drain hole + tube in those low points of the cowl?

Another local buddy had rust on the RH side as pictured above by wayner. Had to cut out an area and patch in a handmade panel. So, yep even the galvanized cars are not immune to rust. On a car that's used fairly often in all types of weather, it's going to happen at some point.

That area pictured by wayner is one that is commonly packed with a lot of road debris like rocks, sand, bits of asphalt, roadkill remnants. Really surprising how effectively that area can get filled up in between the chassis and the rocker panel area. When that collection of debris gets wet, the water permeates into the pile of crap and it stays wet for a while. A situation like that is a great way for rust to get a foothold.

On a car that hasn't been anally cleaned in a long time, that location will usually require you to get in there with a long screwdriver or rod and jab the crap loose. Once you break it loose, you're surprised how much crap starts to fall out. When washing the car, after you've knocked free the packing of crap by hand, definitely a good place to spray your hose aggressively to keep it free of crap buildup

I just found this picture and had to add it here.

There are plenty of pictures of bad rear parcel shelves, but this is the best picture that I have ever seen of what the underside of the rear sheet metal looks like after the rear seal has leaked. (this one has already had the parcel shelf removed, so by the time the sheet metal rusts though you know that you have problems inside the car).

Here is the complete thread:http://forums.pelicanparts.com/porsche-911-technical-forum/643329-72-rust-repair-long-overdue-update.html

http://forums.pelicanparts.com/uploa...1323063833.jpg

Here is another galvanized car that is starting to age.
This time it is a picture of a 964 with the slightly modern window seals.

Keep an eye on those seals!

http://forums.pelicanparts.com/uploa...1393000687.jpg

Even the newest 964 is 20 yrs old. Lots of cars can look really bad after 20 yrs of regular use, especially if they've seen winter use in the rust belt where I live. Road de-icing materials are NASTY stuff around here. I see 10 yr old cars that are starting to rust way too much, like for instance my 2005 Suburban under the doors and rear lift gate

If you come across a car for sale with that sort of window rust, is that a show stopper?
Just don't open that can of worms? Keep looking?

If you come across a car for sale with that sort of window rust, is that a show stopper?
Just don't open that can of worms? Keep looking?

If it's that bad on the surface, it's going to be MUCH worse underneath. I would be willing to bet that if you pulled that windshield out and did some grinding on the sheetmetal in the windshield frame valley, you'd break thru the metal due to so much rust.

They're not all trailer queens. For someone with a welder and time it's no big deal. Not handy and want a cupcake? Keep shopping. I wouldn't be scared personally if the mechanicals were solid but then again I like winter projects that soak up evening hours. They help keep the mind fresh.

That 964 shot is a good example pic. That fender gasket lifting is another common place they rust. If your gaskets look the same then water is getting in there and it will rust. Galvanizing is great but water sitting in one spot will eat galvanized steel as well.

I have no problem with some people being scared away and other jumping into a project. My concern is heeding the all too common advice "don't worry, later cars are galvanized."

To paraphrase KTL, "yes, but it is still 20 years old.."

My advice, as always, check your seals and stop the carnage

I have one small leak in the bottom right corner of the windshield. I pulled up all the carpet in the cabin and found no rust (THANK GOD!!).

Sometimes you get lucky and sometimes you don't.