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JohnJL 06-25-2005 09:48 PM

Cleanup of 'salts' on aluminum parts
I've been using a parts washer and soaking overnight/circulating the degreaser. As you can see in these pics of my cam towers and on the valve covers, there are lots of "salt" deposits. They are crystals, and in some cases are very well stuck to the aluminum. They come off with a scotchbright pad, but there are some spots I can't reach well. Carb cleaner seems to desolve them some, but not all and still need scrubbing. This stuff seems to be forming in the degreasing process, or maybe I just see it only after all the gunk is gone.

I am thinking there has to be some kind of solution I can dip the alu parts that will dissolve the salts easily, like baking soda/water, lemon juice, or ammonia.

Any suggestions? I don't want to damage the parts experimenting.

Fishcop 06-26-2005 06:22 AM

Pretty sure it's aluminium oxide... not much you can do but polish it out, there may be pitting left behind.

rw7810 06-26-2005 11:16 AM

A light bead blast works well too.

cgarr 06-26-2005 02:30 PM

Are you in a wet climent or neer the sea? The engine should be coated with a protecting coating LPS3 etc, to protect the alum. As the factory didů


JohnJL 06-26-2005 10:00 PM

The engine did have a ummm...'protective layer' of grime on it. I soaked the parts overnight in my parts washer/degreaser and they came out with yellow-ish crystals that, when washed with water, end up looking like those in the pictures. There is some pitting in places, enough that the mating surface of the cam towers looks like it should be milled a bit.

These salts became apparent only after the degreasing, and seem for the most part to form over a place where the aluminum pitted a bit underneath.

Maybe a dip in a weak water/phosphoric acid mix, or even some wheel cleaner?


cgarr 06-27-2005 03:56 AM

this is what my owners manual says about the engine, "The engine compartment, as well as all engine, transmission, front and real axle assembly surfaces at the factory have been treated with wax based coating for protection against corrosion" it goes on to say if the engine compartment is ever cleaned the coatings should be applied again.


neilca 06-27-2005 07:55 AM

You probably cleaned this parts in a base solution (soap or sodium hydroxide) The aluminum looks "smutted" that is the gray/black look. To make this shine again you need to use an acid solution. There is a tri-acid solution used to desmut aluminum. Its a combination of Hydrachloric, Phosphoric, and another I cannot think of right now. Do a web search for Caswell Plating. The sell a de-smut solution. It should help you with the alumina deposits also.

Good luck,

rick-l 06-27-2005 08:40 AM

DX-533 was recommended to me but haven't tried it. Has anyone?

JohnJL 06-27-2005 02:22 PM

Why would I want to de-smut anything. I love my smut!

goose2 06-27-2005 08:47 PM

I've sucessfully cleaned similar looking deposits with aluminum wheel cleaner from my local FLAPS (Eagle 1, I think). No promises...try it on something that doesn't matter first.

viejopatron 07-03-2005 07:44 AM

After much investigation, I now use cold water, vinegar (acidic) and assorted brushes for 1st stage. For 2nd stage, I use brake cleaner, picks and swabs.

Oddly, the most useful information I found on the Web were sites devoted to aluminum cookware. Are your heads dishwasher safe?

JohnJL 07-03-2005 04:20 PM

Yep, been through the dishwasher. I did them on the "pots and pans" cycle with no detergent. I'll try dipping them in some water/vinegar mix tonight.

I'm not so worried about the outside/cosmetics. I do want to get all those salts dissolved as they feel pretty abrasive and would be trouble if they come loose.


cjr1 07-04-2005 12:18 PM


Not sure if this meets your needs.I have been bead blasting a couple of pieces & it seems to remove the salt residue you talk about.I wasn't to concerned with looks either,but after doing a couple valve covers,well,everything else now looks kind of....nasty.Parts cleaners are good for grease & grime,but to scrub & scotchbrite these parts,not my cup of tea.

Here are some pics of pieces I did.Ialso just started a thread asking about probems doing main engine castings.Not sure what info or experiences are out there.


cgarr 07-04-2005 02:42 PM

What do you guys do to protect the alum after blasting/cleaning??


wholberg 07-06-2005 09:15 AM

I found this link to a company that sells all sorts of cleaning and corrosion protection products for aluminum.

kenikh 07-06-2005 10:29 AM

A friend told me that his aluminum parts on his Mustang came totally clean of Aluminum oxides after spraying them down with a 50/50 mixture of Simple Green and water. He let it sit then rinsed it off, no problems. Worth a shot.

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