Rust Under Battery Mount - Best Way to Repair?

911nut · 911nut's Garage

I have a fair amount of scale coming from under the battery mount in my '82 SC. I need to get under it to do a rust intervention but I don't see a way to remove the mount (it's more like a platform) other cutting with a oxy acetlene torch next to the fuel tank

Has anyone performed this repair? What is the best way to proceed?
Thanks.

911nut · 911nut's Garage

Bump - Anyone? Anyone?

na2ub · 01:03 PM

I believe rust under the battery is part of the front suspension pan. [Edit - I just checked and it is actually the "gas tank support", found here on pelican. It resides over the front suspension pan] It is typically caused by battery acid leakage, and can be brutal. Check under the car, near the front torsion bar mount to see if it has leaked through, and caused more rust in that area. If the affected area is extensive, you probably need to replace the front suspension pan. If the damage is minimal, you might be able to cut out the area and patch with either sheet metal, a piece from a doner car, or a piece of a new front supension pan. Either way, you probably need to cut out the affected area and investigate further. I understand that a torch might be a bit hairy around the gas tank, but a grinder should be relatively save, in my unprofessional opinon. You can always remove the gas tank if you are worried about it - it is not that much hassle once you have drained all the gas out of it.

Doug

gerard vaglio · 03-09-2006, 01:51 PM

I also have a 79 which, if similar to your car, has a type of flat platform the large 40+ pound factory battery sits on.

Mine had some surface scale on it as well so with a little time and a dremel tool I was able to remove the platform. There are only a few welds and it comes off in about an hour.

I saved like, 2 pound but more importantly, I was also able to inspect under the platform and see the condition of the suspension and pan which looked good. I then washed the area out with baking soda to remove any remaining acid and flushed out the entire area with fresh water before painting. That was about a year ago and no rust has returned.

I then relocated a small, 15 pound gel type battery into the smugglers box. This type of battery will not leak acid by the way.

Just try to establish how far the rust has gone and to stop it there. If you can switch to a gel type of battery so you know you have arrested the problem. Post picks of the area and people can tell you what your dealing with.

Look forward to hearing how it goes.

Ryce Stallings · 03-09-2006, 02:34 PM

I've replaced the front pan and tank support on my car. I don't think on an SC that the battery support is a separate piece. I would use a small air cut off tool and cut out the battery support area about a 1/2" in from the edges. This will allow you to see into the closed area and determine the amount of damage. If it can be fixed without major work (say with Por 15) them you can fabricated a repair piece out of flat sheet steel and butt wled it back together. The acid runs down to the front support points for the suspension. You need to really inspect that area. It might not show from the outside because of the undercoating.

911nut · 911nut's Garage

Thanks for the replies.
The old lead acis battery is long gone, replaced by a Westco battery weighing 15 lb.
Looks like I'm borrowing a cutoff tool from work and getting busy this weekend.