Opinions on rust, pics

Pat Crellin · 01-15-2006, 06:43 PM

This is from a leaking battery. I think it may have been going on for a while. I hadn't checked my battery for a couple of months.
Anyway , I cleaned & cleaned with baking soda & water. I hope I got it all.

My question is how critical is this? I was planing on painting the car in a few years due to some dints and dings. The paint still looks good, about a 5 foot car. The car's just a driver and I may keep it forever.

I cleaned, dryed and sprayed it with undercoat as I did on a bare metal spot I found under the car. Should this stop our slow the corrosion to an acceptable pace. Should I be OK for a few years if I keep an eye on it or is this something I'm going to have to address right away?

vanwyk4257 · vanwyk4257's Garage

I would poke around underneath with an awl or sharp screwdriver at a minimum to make sure the metal around the front of the A-arm mount is solid. If the metal above is rusted out like that it could be corroded underneath.

Pat Crellin · 01-16-2006, 04:52 AM

That's my fear. I hope by pouring gallons or baking soda & water I got any acid below. The metal does feel strong underneath.
I've seen some post on Por-15. I understand it stops existing rust but what about the lost metal? Do I leave it? I don't feel like hiding it with bond.

pantera · 01-16-2006, 05:27 AM

I hate to be the messenger but that looks bad. If I'm looking at the pictures correctly it looks as though the battery acid has begun to do its damage. I'd be more concerned with the bottom of the pan(the trough part) underneath. I've had the unfortunate experience of finding this out for myself. The battery acid leaks down under.

As suggested take a screw driver and poke around. Its a necessary evil to check for the structual integrity.

Dan

Elombard · 01-16-2006, 06:28 AM

If you really want to know search around and see some posts on replacing the front pan. Then you will see how the metal comes together there.

Carefully use a hole saw or whizz wheel and open a 2 or 3" hole so you can see down in there. Then you can really get it cleaned out too. Pop Rivet, sheet metal screws a piece of aluminum, or spot weld in a piece of steel over the hole when you are done. That way you can keep an eye on it over the years. I dont think you have hurt the structural part yet. My car was still very driveable and it was just falling apart at the front suspension PUs. You have a long way to go before safety is an issue IMHO. The top part you see in the trunk is mostly a cover. The bottom part of the pan where the Suspension bolts up is the structural part.

Definitely switch to a sealed battery (I am sure you already came to that conclusion). Cheap insurance.

If you really wanted to fix it right at this point you could just replace the cover and not the lower front member. That would be realatively easy and cheap....

ITSAN87 · 01-16-2006, 08:51 AM

Looks like you are in exactly the same situation as me. I would recommend a couple of things.

First scrape all of the undercoating off of that bracket that holds down the battery and you will find a small gap underneath the bracket where the corrosion (and maybe some rust) is living. You should be able to slide a piece of sandpaper under the bracket to clean it up.

Second it looks like you have a little corrosion starting around that circular pattern on the battery tray. If you scrape the undercoating off of that you will find a piece of tar paper. If you peel off the tar paper you should see a metal tab about 1.5" in diameter. Pry up the tab and you will be able to see under the battery tray without cutting any holes in the car. A small mirror works great here. The same is true for the other circular pattern on your tray but I don't see any corrosion there in your picture.

If you don't stop this stuff it will really spread. While baking soda is supposed to neutralize the acid I found a product that works better. If you can find it, try NOCO battery cleaner / acid detector. It is yellow foam spray that will turn pink if there is any acid present. Just keep spraying and scrubbing until it doesn't turn pink anymore. It is very tedious. Good Luck

Elombard · 01-16-2006, 10:26 AM

Good point on the "tab" I forgot it can be lifted. I dont tink they had that on the ealy cars??? I know my replacement tray had it.

ITSAN87 · 01-16-2006, 12:12 PM

I don't know about the early cars or replacement sheet metal parts but the car in the picture you posted should have the tabs under the 2 circular indentations pictured.

Fl Ted · 01-16-2006, 01:48 PM

Get on it asap!!! The acid wicks into the most minute gap, and it looks like rust in the gas tank seam also !!! Scrape off the body shutz to bare metal, neutralize affected areas with the acid cleaner recommended by "itsan87" , treat areas with "Ospho" ( thin like water, will creep into all the places that the acid found) . Then use the topcoat of your choice. I like and have had good results by priming with a "cold zinc" coating, then the "body shutz" . Then get an Optima battery. Use the lead-acid from the P car in your garden tractor!!

Pat Crellin · 01-16-2006, 06:55 PM

Thanks for all the help.
I really poked hard around around the A-arm this evening and it feels strong. I'll do the the battery tray thing this weekend. The gasket around the tank seems to be deteriorating some next to the battery. Will the NOCO and Ospho seap into the tank gasket or do I need to remove it?
I haven't thought of Ospho in years. On merchant ships we used Ospho, in the Navy we used chipping hammers. I thought Ospho was a wonder product.
Where can I buy NOCO & Ospho?

Fl Ted · 01-16-2006, 07:21 PM

Yeah, that tank "seal" is a SPONGE!!! It soaks up any liquid and keeps the tank seam nice and wet. Ask me how i know!! Don't make me post pictures!!! My car is still in pieces. Don't know where to get NOCO. Ospho is available at some hardware stores. Try a net search. Good hunting!!

ITSAN87 · 01-17-2006, 08:30 AM

If your tank seal looks like it has absorbed some battery acid or corrosion, you should pull the tank. Not only will the acid get under the tank coating and attack the tank, there are also some seams and holes in the body under the tank that you should look at. You can't see these areas unless you pull the tank. Unfortunately I speak from experience. As for the NOCO, do a Google search and you will find the company. Give them a call and they should be able to give you a local retailer.

msk1986911 · 01-28-2006, 12:47 PM

I looks as though I have a similar problem as the first post on this thread, although I didn't see that any of the metal had been eaten through by rust. If I remove the "tar paper" must it be replaced with a similar material or can I just sand, prime and paint it? Also, there is a hole in he sheet metal adjacent to the battery, which the PO covered with a piece of duct tape. I assume the metal was chafed by the battery, although it must have been with an older battery because there is no sign of wear on the one currently installed. Should I try to patch the hole or leave it alone? A picture of the battery area is attached.

The car is an 86 911 coupe.

Thanks.

Kenny Fignewton · 01-28-2006, 02:20 PM

Neutralize all the acid as the posts have mentioned. Then remove all the loose paints chips. Coat all the rust with POR15. It is amazing stuff. You don't even have to remove the existing rust, it will "seal" it in.

Pat Crellin · 01-28-2006, 04:56 PM

Funny this came up today. I just came in from removing, cleaning & painting my gas tank. I cleaned, primed & painted the battery tray last weekend.
So glad I removed my tank. It didn't look bad until I started removing the seal and found a loose area of coating the size of my fist. No damage to the coating, it was just loose. The area was full of the white powder the corrosion leaves & the tank was rusting. I'll let the paint dry & put it back togeather tomorrow.
I'm still concerned about under the battery tray. I think I've got enough, baking soda, NOCO & Ospho to slow anything down for now. I'm thinking about drilling a larger hole to see where I can't see. Any other suggestions?
I just cut out the paper covering the holes & prized it up. I wish they were bigger.
For NOCO I called corp in Ohio for a store in my area. Ospho, I found at a True Value hardware store. Alot of work for a f=$k~^g battery. never again.

rust never sleeps

ITSAN87 · 01-30-2006, 07:26 AM

I had the same question about drilling some holes for better access. I asked a friend who is an aerospace engineer if the structure would be weakened by drilling some holes. It depends on where you drill the holes but for the locations I suggested, he strongly advised against it. Also since you have pulled your tank, you should see sort of an oval shaped slot in the frame member on the drivers side under the tank about a foot behind the battery. Look in there for corrosion that may have spread. (I asked the engineer about making this opening bigger or at least round but he also advised against this. Porsche probably cut a slot here instead of a circular hole for a reason). Bottom line: don't cut any holes unless absolutely necessary or if you can weld in some new material. As for visibility I got a real small diameter inspection mirror and a miniature flashlight. With the factory holes I can see pretty much everything (I think). Good luck, be patient and persistent.

Zeke · 01-30-2006, 07:48 AM

I believe ITSAN87'S engineer friend is a little too conservative. Small holes seem to be OK and if you are clever, you can buy some snap in caps beforehand and then drill to size. No welding needed and future access is easy.

AFA treatment, all of what has been stated is good. The thing is, don't have all these products working at the same time and against each other. If you use baking soda, rinse it out. The ospho types of treatment are meant to be left to dry with no rinsing. Then you can use the POR 15 or favorite sealing product (there are many).

After detailing the concealed areas as much as possible thru the new access holes and using a variety of bendable shaft wire brushes, air and a vacuum (I usually stick the vacuum hose on one hole, then the next, while blowing compressed air in the cavity), you can treat the inaccesable parts first with any POR 15 (or =) by pouring in a small amount and then blowing it around with the air nozzle. I make a bendable air nozzle out of brake line to angle in every which way. This can be messy, so be prepared.

After the POR 15 dries, treat more withthis Go to the purchase online page and buy the spray cans. Treat all cavities periodically as they explain in their rust inhibiting program.

Ron.G · 01-30-2006, 08:05 AM

To The red car with the duck tape. That is not from the battery. That is the bumper shock mount located inside the fender well that traps dirt,salt,mud ect and rots right through to the front trunk area.

sorry.

Rot 911 · 01-30-2006, 08:14 AM

Here is a similar thread from a couple of months ago with the same rust issues: Rust by battery

tsuter · 01-30-2006, 08:15 AM

Quote:

Originally posted by Ron.G
To The red car with the duck tape. That is not from the battery. That is the bumper shock mount located inside the fender well that traps dirt,salt,mud ect and rots right through to the front trunk area.

sorry.

Yep...that's rot thru from the outside. Remove the chin valence, bellows...and I bet there's a real mess lurking up in there. The PO probably knew it and used duct tape to try and stop water from coming in his trunk adjacent the battery.