VikingTrad3r

hi guys, the patient here is my 86 coupe. It was a coastal car for the majority of it's life.

when I first brought the car home I slid underneath it and for the first time I saw Rust on a C4 frame.

then when I remove the interior I looked down by the parking brake lever and I see Rust at the seam between the parking brake lever and the frame. Photo attached.

parking brake assembly is on the left side of the photograph you can see the cable as it drops down underneath the car
I started to pick at the surface rust and vacuum up the rusty dust, and began peeling back the white glue/resin/fiberglass coating. I expect that this is OEM and it was used to seal the inside of the car down against the frame.

I continue to pick away at it knowing that I would have to replace it, and eventually I picked right through and I can now see down through to the floor. Note that it is not a hole in the metal. rather it is just the space between the steel housing where the parking brake cable drops to the floor and the metal frame on the driver side.

i've picked away and you can see where the galvanized framing changes colour into the surface rust.

no, I have no problem at all picking this way and treating it with a rust converter to completely eradicate the rust. I will have to put a tarp underneath the car so the acid does not eat away at my concrete.

drcook

I use a product called OsPho http://www.ospho.com/ I get it in quarts from Ace Hardware and gallons from another place here in the Akron area. I have had good luck with wire brushing the area to get the rust out and then killing it with 1 or more applications.

There are other products that others have used, this is just one that I have.

After killing the rust, painting with a rust killing paint, or a rust sealing paint, such as Por 15

http://www.por15.com/

would then be appropriate

Be advised, if it is rusting there, it could be rusting other places, so you should go on a rust hunting mission and deal with it all at once if you intend to keep the car.

Tom400CFI

Man, Maybe the stuff Drcook has used works...but I've not had good results with "rust converters". The only method I've found that "completely eradicates rust"...especially in any kind of humid environment, is removal of the corroded section and welded in replacement. Rust sucks.

Joe C

if it's still structurally solid, about the best thing you can do is clean, convert, and encapsulate, and hope for the best. w/Tom400CFI, the only true way to repair is to remove and replace, however, with these C4's, that may not be an option.

you have a better chance of slowing down the rusting process if it's surface rust that you can see and treat. the problem lies with rust you can't get to for treatment. I have in the past, drilled access holes, and sprayed in rust converters. can't say how well it works, but if that's your only option, then that's your only option.

http://www.eastwood.com/paints/rust-...FcG2wAodYcAAtA

I had a similar issue with the steel frame in my 85's drivers door - I cleaned the area, used a rust converter, and top-coat with POR-15. fingers still crossed, and hoping for the best...


BTW, this is a handy tool for cleaning rust - harbor freight mini-scaler...

drcook

I have 2 of those mini-scalers. They work pretty good.

I agree that with serious rust the absolute BEST way is to cut it out and replace the section. If it is more surface and you can get through most of it, killing it with phosphoric acid (OsPho) or other chemical rust killer buys a bunch of years.

If you really want to deal with it, but will take a lot of work is to seal off areas of the car and sandblast the rust area with a portable spot blaster.

http://www.harborfreight.com/portabl...kit-37025.html

but they are messy.

VikingTrad3r

Hi Guys. Thanks for the feedback so far and look forward to other feedback as well.

I can confirm it is all surface rust.

i like that descaler ill pick one up.

any comments on the white colored glue/filler that i have been scraping off theview the rust underneath?


what would be an oem equivilent to fill that gap?


cutrent plan as has been laid out above is to peel back that filler to scrape off the surface rust and convert it with ospho then use por 15. the galvanized frame is rock solid. im actually impressed and surprised.

drcook

Harbor Freight also has inexpensive 1/4" air motors and cheap wire brushes. get one of those also PLUS SAFETY GLASSES. rotating wire brushes sometimes lose their bristles and you don't want one in the eye !!!

Between the descaler and a wire brush (even if you have an electric drill to spin it with) will get the metal pretty clean.

hcbph

I haven't had to deal with rust on a Vette but I have done a lot with snow blowers:
First this: http://www.eastwood.com/eastwood-100...e-blaster.html
Followed by Evap-O-Rust
Then a good rust inhibiting primer
Finally painting.

I had some severely rusted snow blowers and they're still fine today after this treatment.

mtwoolford

Ospro (?) works pretty good; if you can't find it, "Jasco Metal Prep" is chemically the same thing and might be easier to find:

Now a couple of caveats, Oshfo (or whatever) or jasco metal prep which I really like because it has the consistency of water and works itself into every, crack, nook and cranny, has to be removed completely after its done its work, i.e. repeated applications of Jasco over a couple of days, it will get every bit of the rust, even tiny pits. Flush it multiple time with water, then work in a solution of baking soda and water to kill any last bit of the acid and the flush that with water. blow everything out with compressed air, give it a last clean with a shot of brake cleaner. Now you're ready to "encapsulate" it with POR15, Naval Jelly, Corraseal or some other such rust preventer / stabilizer. Then prime, paint etc. As a primer, or top coat for that matter I really like "Zink It" a spray paint with a really high concentration of zinc...cold galvanizing in a can, kinda..but the stuff works.

Now don't let this scare you. Just how aggressive Jasco Metal Prep was brought home to me when I put a set of oem hydraulic lifter retainers in a pot of Jasco, went away for three months and when I came back, all that was left was a collection of spidery skeletons.

And for what its worth, there is nothing ferrous based that won't rust, even if its galvanized, painted, powder coated, epoxy coated, whatever, if exposed to water, oxygen, and especially chlorine as in NaCl otherwise known as salt.

mtwoolford

check the frame underneath the battery tray

drcook

You do not need to remove, nor neutralize OsPho. Once it reacts and dries, it is good to go.

http://www.ospho.com/directions.htm

VikingTrad3r

thnx will do. il upload photos of what i find.

i watched a set of videos where it was very clear that you needed to rinse off the ospho after its application. otherwise there is a powdery residue that does not allow proper biting into the base of the next coat.

https://youtu.be/-yA8q4K-_Bo

drcook

The directions from the Ospho company themselves (which I posted) say to just brush off the powdery residue if any develops. If you go trying to rinse off inside your car or other places, you are going to get water somewhere else it is not supposed to be at.

I have never rinsed it with water. I simply brush off the powder and paint. If you go putting water into those areas you showed pics of, you are going to have to let it dry out for quite a while, or you will seal water down in the cracks.

But if someone on the internet knows better than the company that makes it, then it must be true.

VikingTrad3r

yeah. i will treat it and wipe off excess powder. then hit it with high zinc paint. thnx!

drcook

DO wear at least a dust mask if you are under the car, or in a confined area. The fumes from acid will attack your lungs.

I use a spray bottle to apply it, so some droplets can get blown around by the wind if you are outside. OsPho does not react with plastic. It comes in plastic bottles. Ace Hardware sells a good grade of spray bottles.

OsPho is one of those things I use a lot. Anytime I see a spot of rust on the frame of our travel trailer, on my diesel pickup, on my diesel tractor, anywhere I don't want rust, I kill the rust and paint it.

The most effective paint I have used is Rustoleum, but it is not the best paint for a car like a Corvette, unless the area is where it can't be seen.

Por15 is expensive, so I used Rustoleum rust killing primer and gloss black over OsPho on the 91 pickup frame I am restoring.

JimLentz

Get a hold of a cheap USB endoscope and find a hole in the frame close to that spot and inspect the frame from the inside. They have become quite cheap and typically have an adjustable light.