best method to brighten our cast aluminum engine parts?
 

so ive been searching all over the place for a good way to bring back all of my under-the-hood cast aluminum parts to a factory look. im not asking how to polish them, i just want to get them back to their original factory finish. ive tried a few things (aluminum brightener, soap/water) but i cant seem to get the grime/oil out of the sand cast, and my intake piping, waterpump, UIM etc etc still looks very dull and aged. i was hoping to send it to an anodizing shop and have it chemically stripped, and then clear anodized, but the shop i called told me that their best guess was that the alloy that the parts were cast of would not take to anodizing, and would turn gray if they tried to anodize it. i suppose my last option would be sand blasting. if anyone has advice please let me know as i want to start reassembling my project car asap. thanks. heath :)

a nice bead blasting works well. use duct tape to mask all the faces and shit u dont want to hit. use multiple layers of it.......just like the pros:icon_tup:

On one R & R ,I sand blasted all the cast alum with worn out sand .The color and finish all matched very well and with the clean plastic stock parts the engine bay looked as good as new, maybe better . The customer was very happy . I did remove alot of the casting seams that were easy to see before blasting . I did the alternator and air pump as well .

I used simple green on various parts. When I did a write up a while back, ppl were surprised how clean the turbos looked. It's said to watch out for certain finishes (like paint), but I never had any problems. Good luck! Lets see that clean engine bay when ur done!

Simple Green will oxidize polished Aluminum surfaces.

just to let you know.

here is what I did. https://www.rx7club.com/3rd-generation-specific-1993-2002-16/nice-way-clean-brighten-uim-504318/

bead blast it, paint and clear it.

or just leave it be after blasting. natural looks best

yeah im somewhat worried about using simple green. ill try it with one of my spare parts. my engine bay is REALLY clean at the moment... ;)

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/return-my-20b-project-717909/

I am using castrol purple degreaser and a dish scrubber... works awesome, then i am painting all of the aluminum parts with 'aluminum look' high temp enamel. All of the iron peices will be black.


Its going to look awesome.



=Ben

i used afm cleaner it took of all the dirt and grime off and it evaporates quickly

using sand as blasting media will leave your parts with a dull gray look, what you want to use is glass bead...... glass leaves a shiny metallic finish.

thanks i just bought a cheapo media blasting box on ebay and some glass bead media. ill post some pics when everything arrives and i have a..... blast. sorry i couldnt resist.

Even bead leaves a flat/satin finish, it actually removes any shine inherent to cast aluminum. The best thing I have done is use greased lightning. Spray it on a warm engine, not hot, but not dead cold. Let it sit 5 minutes, spray more. Repeat several times depending on how dirty it is, don't let it dry completely.

Then start the engine and pressurewash it while it is running. Don't spray right into the alternator too much, expect a lot of steam but it won't hurt anything. Keep it running for about 10 minutes until most of the engine parts have dried.

You can always powdercoat any of the metal parts.

I picked up a spray-on/rinse off alluminum cleaner at the auto parts store. Worked like a demon with a little scrubbing.

Do you know who makes it?

I'll have to look at it when I get home.

+1 for Super Clean. The key is not to leave it on for too long. Brush it in for a thorough cleaning action and wash it off immeadiately. Repeat for heavy deposits. This works good to get back to the factory look. Again, do not leave it in contact with aluminum for any period of time as it will react and dull the finish.

There are also phosphoric/sulfamic acid based products available that will do a really nice job of cleaning and brightening many metals, including aluminum; saftey precautions apply.

I used some automotive hand cleaner on mine. I think it was "Fast Orange", or something like that. It worked pretty well.

carb or brake cleaner from any autoparts store works as well. just have to try not to get it on plastic parts. they do eat away a layer of plastic and weakens it overtime.

Something else you can consider, if you want to keep a stock non-flashy look but cut down on maintenance in the future. you can have the metal parts blasted and then clear powdercoat over that. It'd look either satin or glossy depending on what clearcoat was used, but would retain the stock bare aluminum color while outlasting clear paint.

OF course, this is just as much work as powdercoating in color/metallic, so I don't see many people doing it that way.

what i said was from personal experience :) , clear powder coat over cleaned cast aluminum will also result in a gray/paint primer look but glossy and clear spray paint will turn yellow and peel with time.

RotorMotor - make sure you put down a tarp or something similar so you can reclaim your glass media because it will go through the machine really fast...

here is a picture of a rotor housing i blasted with glass media i took the picture today but the housing was blasted 7 months ago and its still looks good. :icon_tup:

https://www.rx7club.com/attachment.p...1&d=1201239734

That's odd, you must use a very fine medium. I use tptools "speed bead" which cleans VERY well and VERY fast. Here are some pics of parts I blasted last week, all bare aluminum. You can see the satin/rough finish it leaves, which is in no way shiny and will actually stain easier than when it was new cast aluminum.

http://www.rotaryresurrection.com/kl...m/DSCF3356.JPG

http://www.rotaryresurrection.com/kl...m/DSCF3355.JPG

the glass i used for the rotor housing was 80 grit, i get that same finish (like yours) when i use sand.... stains like paper but works better for powder coating.

try glass you won't be disappointed.:icon_tup:

I DO USE GLASS, NOT SAND

Above are pictures of glass beaded parts. Here is the product I use.

http://cgi.ebay.com/ebaymotors/Speed...6349QQtcZphoto

Compare strip times for standard glass bead versus speed bead.

http://users.zoominternet.net/~tptoo...ve-basics6.jpg

easy guy... you misread my post because i never said *you* use glass or sand, what i said was.....

A. *i* use 80 grit glass.

B. *i* get the same finish (like yours) when *i* use sand.