Cleaning up porus aluminum

[TraceZ]

I'd like to somehow bring back the luster of some porus aluminum parts under the hood. Namely the intake manifold, alternator and alt bracket.

Is there a chemical that I can put on the porus aluminum that will act like an acid and eat it clean? I'd like it to look new again with that luster and clean appearance. It currently looks kinda dull.

[AmericanZ28]

Ive used Industrial grade Spoke Cleaner before (acid), and it worked great. You just kinda have to be carefull that it doesnt dry, because it can leave drip stains on your stuff. A pressure washer will certainly help in getting it all to look evenly clean.

[Injuneer]

Of course a "pressure washer" would also run the risk of damaging sensors, the PCM, electrical connectors and the infamous Optispark. I personally would avoid using a pressure washer under the hood.

First clean the grease and surface dirt off using a solvent type cleaner on a rag. Then try aluminum polish. Applying it with a felt "bob" on a a rotary tool will help speed the process.

[Joe 1320]

Eagle one etching mag wheel cleaner. The stuff works great, but don't leave it on too long.

[wolfdogs]

small dremmel.

[fastTa]

I used a product called "Wenol". It was really good at polishing my WS6 wheels so I though I would give it a try on my stock LT1 intake manifold, fuel rails, and alternator. It made my intake manifold look better than new!

And yes a dremmel would definitely make things easier.

[Fastbird93]

I used a product called "Wenol". It was really good at polishing my WS6 wheels so I though I would give it a try on my stock LT1 intake manifold, fuel rails, and alternator. It made my intake manifold look better than new!

And yes a dremmel would definitely make things easier.

Wenol is some of the best metal polish that money can buy.

[TraceZ]

Wenol is some of the best metal polish that money can buy.

The aluminum on the items I need to clean is not smooth, it is very rough and porous. I'm worried that if I use a polishing compound on it that the compound will get stuck in all the little ruts and look worse than it already does.

Feedback?
I could be wrong.. tell me if I am.

[Joe 1320]

I'm tellin' ya.........

Eagle one etching wheel cleaner. Use it on the rough cast aluminum, use the polishes for the fuel rails. I've used the stuff on cast aluminum for years. I did my intake when it was off, I've done it on others' cars with the intake in place and the result was stellar. No pressure washing needed, just simple rinse off. Just keep the water off the opti.

[TraceZ]

I'm tellin' ya.........

Eagle one etching wheel cleaner. Use it on the rough cast aluminum, use the polishes for the fuel rails. I've used the stuff on cast aluminum for years. I did my intake when it was off, I've done it on others' cars with the intake in place and the result was stellar. No pressure washing needed, just simple rinse off. Just keep the water off the opti.

Thanks Joe. That is the explanation and info I was looking for. I'll give it a shot.

[Injuneer]

The alternator bracket is fairly smooth after you get the dirt off. It will respond to polish. The alternator case seems to have been blasted or something... surfaces like that can be cleaned, and it you want to really get into a bit of work, can be polished with sandpaper and polishing compunds.

The fuel rails as noted above simply need some aluminum polish on a soft rag. I've had good luck with the Mother's Amazing Billet Polish. The top of the intake has fine lines in it, but will respond to aluminum polish. I don't know about the surfaces of the LT1 intake, I know my old one was fairly rough.

The stock throttle body can be polished. The Holley aftermarket responds extremely well:





If you want to get the rough surfaces smoothed, you can sand sttarting with 200 grit, go to 400grit, then to 600 grit paper. Then some polishing compound on a Dremel/felt bob. Sears has some polishing compund that seems to work better than jewelers rouge. I did my Baer brake calipers this way:

[Black97]

At work we cleaned large aluminum parts with some air conditioning coil cleaner. Don't remember the name of it and I don't know how bad it is for the rest of the stuff under the hood. But it really cleaned up the parts real well.

[fastTa]

The aluminum on the items I need to clean is not smooth, it is very rough and porous. I'm worried that if I use a polishing compound on it that the compound will get stuck in all the little ruts and look worse than it already does.

Feedback?
I could be wrong.. tell me if I am.

When I applied the Wenol to the rough porous surfaces of my intake manifold, I rubbed it in until it turned black. Then let it sit for a few minutes, and then use a cotton towel to remove the polish. The roughness of the towel will remove all remaining polish and it will shine beter than new.

I helped a friend sand and polish some of his brackets and alternator and it wasn't to bad. We used a dremmel and sand paper basically in incremental grits like Fred described.

Then once you get a fairly smooth surface you use a substance called Tripoli Compound. It is bacically a metal specific poilishing compound. It works fantastic. Then you follow up with a metal polish and you have a mirror basically.

[TraceZ]

I used the mag cleaner stuff today on the alternator. It got it really clean, but it still doesnt have that sparkly sheen like new.

It looks a ton better, though. I'll try Kevin's wenol idea next and see what that does to it on top of what I've got already.

[Dave M]

TraceZ, let us know what works, I've been thinking about the same process.