# Etch priming over corrosion on wheels... bad idea?



## Franzpan (Mar 2, 2009)

Is it a bad idea to etch prime over corrosion on alloy wheels?

I'm refurbing a set of Toyota wheels with bad corrosion all over the wheel barrels. The surface has a ribbed finish to it so its very hard to sand the corrosion back to shiny metal however it is smoothing down nicely.

How long is the finish likely to last if I painted over the black corrosion? the wheels are from a 12 year old Toyota so if I got 3 or 4 years from the finsih I would be happy.

Obviously taking the corrosion out fully is the right thing to do but it would take a weeks worth of sanding.


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## steelghost (Aug 20, 2015)

Aluminium is not like iron in that the corrosion doesn't physically expand. So if you protect it, it should last reasonably well. As long as it's mechanically sound and you're not expecting an amazing finish, I think you could expect a few years out of it.


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## Sh1ner (May 19, 2012)

A picture might help. Aluminium corrosion is usually white not black?
If it is black some wheel acid may remove it.
Would it be possible to have them soda blasted and then etch primed? Much less effort.
If you paint over corrosion any paint will just flake off.
Aluminium oxidises in a different way to steel, which is why you use an etch primer to break down the very thin layer of oxidation that occurs instantly on aluminium that has been cleaned.
If it has that thick white crusty look it cannot be penetrated by the primer.


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## Tintin (Sep 3, 2006)

I have been refurbing my alloys. After removing the rust with a power file, several coats of primer, including high build primer, I could still feel very minor pitting, bumps and undulations. I used Dolphin Glaze, which is a very runny self levelling filler, sanded and primed again, and the pitting/uneveness has pretty much gone.

You can get your wheels powder coated for around £35 each these days. If the car is worth a bit, that might be a better option.


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## Franzpan (Mar 2, 2009)

I'll get a few photo's up tonight to show the corrosion. Its a £1000 car which I'll be running for only a few months so don't want to be putting much money into it, I'd still like a good finish that lasts mind.


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