Cooling fan corrosion

[rscavallo]

What is the easiest method for removing corrosion from the cooling fan on my 69S? Maybe I should ask Richard Griot? Thanks..

Thanks.
Ron Cavallo #138
Sebastopol Ca

[Fixer]

All of the early 1.3:1 ratio fans are a magnesium alloy of about 90% Mg/8% Al/2% trace elements such as Silicon, etc. Aluminum oxide is white and anything with a majority of Al is whitish/chalky-looking when oxidized, whereas a majority of Mg, which oxidizes grayish-black and looks dark gray or sooty when corroded. Magnesium oxidizes, being much more chemically active than Aluminum at a rate 10X faster.

Blasting, Wire wool polishing, and clear urethane [real professional automotive clear coat is best] or rattle can lacquer would work [for a while] but the edges will erode as the fan sucks in fine particles.

[Richard]

Ron,
I had a cooling fan and housing that had been painted yellow by the previous owner. I took everything apart and bead blasted the fan and housing. This removed the paint but left the overall look a little too shiny. I sprayed it with some Gib's penetrating oil, wiper off the excess and it came out very well. It has retained the look for the two years since I did it. Based on how mine turned out I'd guess the same method would work on the corrosion on your fan.

Follow-up: I agree with the comments below by beh911. Because you aren't removing paint like I did, I think that all you'll need to do is spray Gibs on, let it soak in and then using something like a toothbrush on the corrosion, clean up everything. You probably won't need to dissemble the fan. It should be a petty simple and easy job.

[beh911]

Ron
2nd for Gibbs. Save your money on a restoration and the headache of a disassembly.

Spray it on, let it soak, maybe a toothbrush on the heavy oxidized sections, and wipe off excess. You will be amazed

[Fixer]

I have to agree that Gibbs is good stuff and the look is nice enough.

[Tdskip]

This?

[37yrold911]

yes, that's it

I am not certain it is any better than similar products tho

[Soterik]

Ron,
Given the originality of your car, I think I would be more of the mind to preserve rather than restore. Overdoing it in one area might detract from the rest of your cars original patina. The gibbs type products might be your best solution. Here's a thread regarding restoration, and Mark Motshagen's talent in doing these fans. I'm having him do mine for a current restoration.

http://www.early911sregistry.org/for...ight=motshagen

Regards,
Eric

[304065]

As brilliant as Mots is, it's not original. That said I'll probably have him do mine on the other side of Jay Peak concours.

Don't use steel wool of any kind (or even a wire brush) as the steel will embed itself in the magnesium and corrode.

Drill out hub rivets
glass bead everything
Cad plate hub with clear chromate (silver color)
rivet hub back to fan (it only goes on one way, rivets are simple, don't use screws)
call it cool

[Richardnew]

It's a loosing battle. I've polished my fan. That lasted about 3 days. I'm going to try the Gibbs. If that doesn't work then I'll go for powder coating.

The good thing is that since my CIS system was removed about 40 years ago I don't have to worry about being original. Ok, my interior is original. Does that count?



Richard Newton
When is a Restoration Done?