getting antifreeze stains off Aluminum

[saltshaker]

Has anyone had success polishing antifreeze stains out of Aluminum? How did you do it?
Jon

[N2Cobras]

Try #0000 steel wool and WD40 then polish with Mother's Mag and Aluminum polish.

[twobjshelbys]

What you probably have is not a stain (a chemical interaction) but a residue on the surface. Before abrasives which will require re-blending the surface texture try chemicals solvents. I'd try denatured alcohol first.

[Daytona Dek]

Along a similar vein what is the best method to brighten up an alloy inlet manifold without taking off and polishing. Wire wool or mag polish will be very hard work. Is there a chemical alternative? Would denatured alcohol work? BTW what is it?

[mrmustang]

Originally Posted by N2Cobras

Try #0000 steel wool and WD40 then polish with Mother's Mag and Aluminum polish.

This ^^^^

I hear Margaret has it in stock, in fact I know she does as we were there yesterday


Bill S

[N2Cobras]

Originally Posted by Daytona Dek

Along a similar vein what is the best method to brighten up an alloy inlet manifold without taking off and polishing. Wire wool or mag polish will be very hard work. Is there a chemical alternative? Would denatured alcohol work? BTW what is it?

Denatured alcohol is isopropyl alcohol aka rubbing alcohol. You can try with something easy like a mild chemical then progress to a stronger chemical and if that doesn't work, a lot of elbow grease and time with steel wool. I agree, it will be a chore to clean it up with the manifold on the engine and to get a uniform appearance. Taking it off as a winter task might be your best choice.

The OP didn't state what they were trying to clean, top of valve covers is one thing, other components with more nooks and crannies are more challenging.

[twobjshelbys]

Originally Posted by Daytona Dek

Along a similar vein what is the best method to brighten up an alloy inlet manifold without taking off and polishing. Wire wool or mag polish will be very hard work. Is there a chemical alternative? Would denatured alcohol work? BTW what is it?

Denatured alcohol is my go to first solvent. It's much less harsh than petroleum solvents like paint thinner. It also (at least how I've used it) never affected color, so if you spill paint on carpet denatured alcohol will help remove it.

What is it? The denatured part is some chemical that is added to our favorite beverage, ethanol, to make it "taste bad". Ie, it's everclear with something to make it taste bad, smell bad, or nauseating. The federal government actually regulates it (since it is alcohol sold without tax) so there is a list of formulas.. From experience, some different brands can leave a "haze" on highly polished surfaces like glass/mirrors so if you want to reduce that just use everclear.

PS. Your application doesn't sound to me like DA would work. But you never know. Standard solvent disclaimers apply: Try it on a small area that is hidden from view.

[twobjshelbys]

Originally Posted by N2Cobras

Denatured alcohol is isopropyl alcohol aka rubbing alcohol. You can try with something easy like a mild chemical then progress to a stronger chemical and if that doesn't work, a lot of elbow grease and time with steel wool. I agree, it will be a chore to clean it up with the manifold on the engine and to get a uniform appearance. Taking it off as a winter task might be your best choice.

The OP didn't state what they were trying to clean, top of valve covers is one thing, other components with more nooks and crannies are more challenging.

Not quite. Rubbing alcohol has less alcohol than denatured alcohol. Rubbing is typically (from my bottle) 70% isopropyl. DA is from ethanol. They are not the same chemical. Pure isopropyl cannot be consumed. Pure ethanol is sold under the brand name everclear which can only claim to be 99% (198 proof) because the instant you open the bottle it starts to absorb water molecules.

Also as a solvent since RA is only 70% alcohol it will leave more of a hazy residue.

If you're looking for it and can't find it then look for fuel for camper alcohol stoves. It's the same thing. My local Home Depot had DA in 1 gallon but no quarts (not by design, just a temporary stocking issue). They had quart alcohol stove fuel...

[Blas]

I have used both fresh antifreeze and simple green to remove old antifreeze stains.
Blas

[twobjshelbys]

Originally Posted by Blas

I have used both fresh antifreeze and simple green to remove old antifreeze stains.
Blas

Yes, in fact, there are many instances where the best solvent for something is itself... The stain is the coloration and other solids after evaporation so more antifreeze would bring them back into suspension. Just use water or something else to clean up afterwards.

Also, what is the surface below? Is it polished? You might need something like a toothbrush to get it out.

[incoming]

please be very careful with the Simple Green. It is slightly caustic.

[saltshaker]

Thanks for all the responses, tomorrow I’m going to give all of them a try and I’ll let you know the results
Jon

[twobjshelbys]

Well?

[saltshaker]

the antifreeze didn’t work, WD40 and steel wool was marginal, compound with a felt pad on a angle grinder was best but it also polished the aluminum.
Jon

[Blas]

How long were these antifreeze stains been on the manifold?
Been baked on multiple times?
I have always had great results with either liquid on a small
square of paper towel soaking, sometimes overnight. But the spots I clean have not been repeatedly roasted on.
Blas

[twobjshelbys]

Well, you've already altered the surface with the grinder so I guess I won't ask if the denatured alcohol did anything. (But I'm asking anyway.)

It is true that for some of these solvents extended soaks may be needed. DA is hard because it evaporates almost instantly.

[incoming]

Many many moons ago in a far away place, our silicone coated missiles would sometimes come back from alert with hydraulic fluid on the skin. Sometimes the silicone had soaked up enough fluid to bubble up. Our SOP was to take cheesecloth and soak it with naptha and secure it over the "wound". We'd basically undress it twice daily and check the "wound". The naptha would eventually draw out the fluid and all was good. Just an idea?