Rust found in pan and firewall! Any ideas?

andrewro · 02:05 PM

Hello everyone,

I began reading this forum recently, and regrettably, my first post is about some rust I found over the weekend in my 1972 911T coupe.

I try and check the car over every year or so, whenever I do a valve adjustment. About a year and a half ago, things were fine. This weekend, while preparing to service the car, I gave it a once-over in search of any structural rust.

The first thing I found is that I have rusting in the front suspension pan, on the right-hand side:

A few years ago I had the pan patched as a stopgap, and it looks like this is now rusting through. I have searched the forum and read some of the pan replacement links. I cannot weld, nor do I have a shop facility. It is possible that I could help in disassembling the car if the work could be done at someone's home. I did see a thread here where some Atlanta people were discussing pan replacements. I am about an hour from Atlanta, and I was hoping to ask if anyone could point me to a good home-shop where I could have the pan replaced.

However.

When it came time to begin my valve adjustment, I noticed that the upper section of the firewall is also rusting away! The pan was a jolt when I saw it, but the firewall was a gasp followed by an awful sinking feeling. It appears water is getting in through a worn rear glass seal. There is a rusty gap running most of the length of the firewall.

The good news, as far as I can tell, is that the vertical portion and the seats appear to be okay. I have not pulled the seats though - I have knocked around underneath them while under the car. The carpet in this car is mostly out right now. I had another, smaller leak recently and I removed it to prevent trapping water against the floorboards.

At any rate, I was hoping to become a member of this forum and talk about the treasures these cars are, but unfortunately I am instead asking for suggestions and general input about these areas of my car. I have been aware of areas to check for rust since shopping for this car ten years ago, but somehow I just wasn't vigilant enough. The rear shelf seems to have rusted fast!

It is good to be on here with fellow Porsche enthusiasts, regardless of my bad news. I look forward to everyone's opinions.

Regards,
Andrew

jpnovak · 09-07-2005, 02:12 PM

Welcome Andrew. Your problems are not uncommon on a 30+ YO car with a non-glavanized body. These repairs can be easy for a DIY type but accumulating the tools can be expensive.

First I would suggest pulling the rear interior to see how bad the rust is under the upholstery panels. Be prepared, you may find more rust. Don't worry there have been pictures of much worse!

I am sure someone from the Atlanta area could help out. You should also contact the local PCA for recommendations. Of course, if you want to learn to weld we can help with that too!

FrayAdjacent911 · 09-07-2005, 02:53 PM

Looks similar, but not as bad as my rust issues! The front suspension pan is toast, so it's got to be cut out and replaced. I'm pretty sure the whole back deck is rusted out... I just hope it hasn't spread too much. The rear seat 'buckets' are a bit rusted where water probably pooled.

The passenger compartment floorpans are a big concern... and I hope the rockers don't need work, but knowing my luck, they probably will. hehe

andrewro · 09-07-2005, 03:21 PM

I'm sure my front pan is toast as well. From these pics, would any of you suggest that I completely stop driving the car until I have a solution?

I felt somewhat better once I read that the firewall isn't a structural element on these cars - that is correct, isn't it? Still, though, it is a lot of work to undertake without any real skills.

I have been underemployed for the past few years and have not driven or worked on this car as much as I used to. Now I am in a better situation, and my plans for the 911 were to spend this fall learning all about grinders and por-15, and repairing some surface rust, in preparation for having the car painted in winter. Then I could enjoy it and keep it serviced until it eventually needs a motor or some such thing.

The structural issues, although not that bad for many people here, are enough to really put me off-budget. I do not have a garage for this car at my house of the past five years. Before, it was in a carport. I might be able to buy one of those freestanding carport / roof kits from somewhere like Lowe's, and pour a pad or put down some nice gravel, but it wouldn't be a perfect situation and it would take away from the care and repair budget for the car.

I appreciate the comments so far! Thanks everyone. If anyone has any questions about the car or the rust I've found so far, I will do my best to answer.

Thanks!
Andrew

FrayAdjacent911 · 04:56 PM

Andrew

You can get the front suspension pan and gas tank support for around $200. Check out Restoration Design. I have heard that some people have had problems getting in touch with them. They make a lot of the pans and parts that commonly need replacing.

I've never done a front pan, but Jamie and I will probably be doing mine in the next few months. He's done a few, and I don't think it's TOO difficult. I'm going to get the gas tank cleaned and sealed, and probably coated with Line X before the pans.

My front suspension pan is MUCH worse than yours (there's a silver dollar size hole rusted through next to the tow hook), and I've driven it. I wouldn't stress it much, though. Yours looks to be rusting around the A arm connection. A failure there could be quite catastrophic, but yours looks more like just some surface rust. You might get on it with a brush and see if it's penetrating deeply. I'd be concerned if it was.

If you do a lot yourself, I don't think the rust repair will be too expensive, but it WILL be time consuming, and sometimes challenging. I don't know how to weld or fabricate patches and stuff... YET... but I'll be learning!

You should see if you can find some local guys with older 911s to help, or borrow tools from. We've got a great small group here in Austin, and between them, I think I could get great help on anything I'd ever need.

ianc · 09-07-2005, 05:42 PM

Andrew, first step is to find out exactly how far the rust has gone. This means stripping off any factory undercoating, carpeting, seats, etc to check the extent of the damage. The most dangerous is obviously near the A arm mount, so you'll want to get that stripped and wire-brushed clean ASAP. Post more pics of your investigation to get more detailed opinions. Hope it's not too bad... If you can't garage the car and you get frequent rain, you might want to cover it with a tarp or some such until you can get the glass seals sorted out to prevent the ingress of further water. Sorry if this is obvious stuff. Good luck,

ianc

Jim Sims · 09-07-2005, 06:33 PM

For cars of this vintage look for rust at the rockers; especially under any deco trim and around the jacking tubes. Also at the body where it meets the back of the doors and where the front fenders attach at the front of the doors. Plus look at the joints where the front fenders attach to the luggage compartment. The area around the fuel filler door and the rear bumper mounting brackets also tend to rust due to trapped debris. A good rule of thumb is multiply the rust you see by a factor of ten to get an idea of the full extent of the rust. Good luck. Jim

andrewro · 09-08-2005, 01:35 PM

This weekend I will get into the rear seat area and see what rust I may have there. I am aware of how rust-prone the rockers, jackboxes, pedalbox, and so forth are on these cars. I have checked these areas fairly regularly and apart from a small patch of rust on the driver's side rocker, I have always been happy not to find any problems. This weekend I will check these areas again, more closely. I also will wire-brush the pan if I can bring myself to face it again! I know I have it to do, but I might wait a week first.

I have seen the Restoration Design parts - I was considering ordering the pan and possibly the tank support too, even if I decide I cannot afford to keep the car and do the work.

I will post more pics as I am able to get into the car and inspect these areas.

Thanks again everyone,
Andrew

Jim Sims · 09-08-2005, 02:55 PM

"small patch of rust on the driver's side rocker" That what we thought was the case on my son's '73 until we started probing the rockers. The rockers rust from the inside out so some firm probing with a wooden dowel might be in order.

Jim