cleaning aluminum intakes

[musclcar]

looking at my edelbrock TR1-X tunnel ram it's a dull spotted gray finish to it.i've heard of a few ways to clean them and they are: 1) bead blasting 2) spray on acid cleaner 3) easy off oven cleaner.i want to get that new intake look and try and keep it looking good.now to keep it looking good is there something like a clear coat or ?? that won't turn yellow or glossy. http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

[Bill Rose]

I sand blasted my intake with a cheap Sears blaster and it came out nice. I used fairly fine sand. I've also found the lacquer thinner is a good product to keep it clean when it's on the motor. I put lacquer thinner in a small spray bottle, spray it on and wipe the stains off with a clean rag..

[Bill Rose]

I sand blasted my intake with a cheap Sears blaster and it came out nice. I used fairly fine sand. I've also found that lacquer thinner is a good product to keep it clean when it's on the motor. I put lacquer thinner in a small spray bottle, spray it on and wipe the stains off with a clean rag..

I don't know if there is any clear that won't yellow.

[Salvatore]

I am not a fan of sandblasting aluminum intakes. I feel it ruins the original aluminum sheen. Like the valve covers clean them real good but not sandblasting. Call Jerry MacNeish, he will re-skin it for you. (Camaro High Performance) JMO Sam

[NCGuy68]

[ QUOTE ]
I am not a fan of sandblasting aluminum intakes. I feel it ruins the original aluminum sheen.

[/ QUOTE ]

I agree 100%. I've tried a number of methods over the years and plastic media blasting works the best for a OEM finish. I then use "Nyalic" from Eastwood to keep it looking factory. Any other coatings will dull, chip, peel or yellow. I've gotten good results from this process.

A alternative is to have MacNeish 're-skin' it. Jerry does nice work, but you still are faced with preserving that finish.

[Belair62]

There is a process that machine shops use where they tumble the piece in something very mild...can't remember what the hell it is though.

[hvychev]

This is a good question for me too. I am going to do mine in the spring on my Deuce along with adding the correct valve covers, water pump, and other cosmetic corrections that need to be made.

Belair, do you know a good place around here that I can take mine to be done at?

[Belair62]

I'm pretty sure it was Fast Times in Morton Grove who I had mine done by...but it's been so long I can't remmber...try calling a machine shop and see if they know the process.

[musclcar]

so your saying a competant machine shop could clean the intake.the tunnel ram also has grease pen or paint pen swap meet prices on it. http://www.yenko.net/ubbthreads/images/graemlins/3gears.gif

[68l30]

I use this "tumble" process at work.It is in a vibratory machine that uses a media as a deburring/polishing agent when mixed with a H20 and oil as a lubricant.It does a good job but will leave a pattern type finish on your part and may also remove any grain on a intake.I use it mostly on hot rolled steel and stainless.It will work very well on aluminum depending on media type and duration of the cycle.I don't care for the finish on aluminum though.Very dull.. http://www.yenko.net/ubbthreads/images/graemlins/scholar.gif


Steve

[Belair62]

There ya go Frank...maybe it's not for you....

[CamarosRus]

...I had my 70 LT-1 manifold STEEL shot blasted(just like when they were mfg at the foundry) at a place that rebuilds Aluminum mostly japanese cylinder heads......not positive but a "Wheelabrator" brand or similar type of machine that they used to run heads thru on a conveyor belt like idea was used....They steel shot is only used on aluminum parts and wasnt contaminated with ferous metal or grease to get into or on intake or my Muncie case.....I'll attach several pics to show you examples of my intake, muncie case, AND muncie DIE-CAST PIECES which I had vibratory/tumbled in ceramic stones with a detergent/chemical cleaner.
I should probably retake these pics in higher resolution, but this all takes TIME......hope you get the idea.

Chuck Sharin Seattle

THE FOLLOWING IS A STATEMENT FROM JEFF BETZ WHO CURRENTLY IS AN ENGINEER WITH DAIMLER-CHRYSLER.....previously with G.M. Jeff supervises in the plant where misc Jeep engines are built.

"Guys, I'm a design engineer that has worked with many cast iron and aluminum parts, and sand cast parts DO NOT have any type of skin on them from the foundry. Chuck is exactly correct when he states a "Wheelabrator" brand cleaning process (or similar version) is used to clean the sand off of a cast aluminum part when it goes thru "shakeout" which is the process of removing the core sand and green sand from the casting process. The type of media used may vary among foundrys, but they are all cleaned using an abrasive. To duplicate the "as cast" aluminum intakes may be a trick, because we need to correctly match that intake as it came out of the shakeout line of the foundry. It's anybody's guess today as to what media was used, and I'm sure that varied from month to month and foundry to foundry.
DIE CAST aluminum parts are a different story. A die cast aluminum part gets it strength from the outer skin that forms against a permanent cooled mold, very different from the sand used in a sand casting that is recycled/trashed after each part. Transmission tail shafts and distributor housings are typical die cast parts. Today, some parts are a mix of a permanent external mold with internal sand cast cores."

http://img.photobucket.com/albums/v470/CamarosRus/Camaro%201970%20Resto%20Details/IntakeA.jpg
http://img.photobucket.com/albums/v470/CamarosRus/Camaro%201970%20Resto%20Details/Muncie1CaseShotBlasted.jpg[img]http://img.photobucket.com/albums/v470/CamarosRus/Camaro%201970%20Resto%20Details/Muncie2Case1970Top.jpg
http://img.photobucket.com/albums/v470/CamarosRus/Camaro%201970%20Resto%20Details/MuncieSideCover.jpg
http://img.photobucket.com/albums/v470/CamarosRus/Camaro%201970%20Resto%20Details/MuncieTailhousing.jpg

[Salvatore]

Very nice stuff! http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[SS427]

Something that works very well for me is I use glass media and then use a green Scotchbrite pad afterwards and put a very slight polish on in. Only the high points of the casting pimples get shined up. This has worked very well and resembles virgin castngs very closely.
Rick

[Salvatore]

Good idea Rick. I have a Z/28 intake that I will try it on. I feel alot of people mess their intakes and especially their valve covers up! Sam

[Charley Lillard]

Same process as Ricks only I use the green scotchbrite pad with warm water and dishwashing liquid.

[Belair62]

THAT's what I was talking about Chuck...steel shot..it make's it look brand new and no patterns...

[olredalert]

--Hey Chuck,

--------Is that Jeff Betz the same guy who just bought a 69 Chevelle wagon from some ol "tuna" up in East China Mi.? Sure sounds like the same guy. He and his Dad are both real nice people. I have heard from him that the 69 (a beautiful original car) will soon have substantially more power and a switch to 3 pedals. Hope we can get him interested in participating here on the board as his knowledge would be cool!........Bill S

[mrrec]

The GM engineer has some good info and I believe a good deal of it applies.

I own a small mfg co and have experience with new alum castings. Not all castings are media blasted, though, after shakeout (removal from the mold) and I don't know what they did in the musclecar era on trans parts and intakes. You can bet there is not one right answer!

Sand castings (intakes, trans main cases) are very bright (almost aluminum paint bright) as cast in many cases. You can duplicate this with an older casting (regardless if it has been blasted before) with a "brite dip" in acid. There are several formulations including 94% Phosphoric acid, 6% Nitric acid. I glass bead first, then dip. Contact time of the acid determines brightness. It works.

Die cast aluminum cannot have the original finish (skin) restored by media blasting. As cast, diecast has a much darker, smoother look. Once you blast it (vibratory, tumbling, media blasting), you're done. I have not found any procedure to accurately replicate this finish (just find a tailshaft housing someone hasn't messed with!).

The "reskinning" thing is a misnomer. You really can't "reskin" (and like the GM engineer said, sand cast aluminum doesn't have a skin anyway). I had McNeish do an intake to see what he was doing and it is appears to be just a media blast (media unkown). I've done the same with glass beads. It does look nice, though.

Cast iron "reskining" by those saying they do that is probably ceramic coating. Sand cast cast iron does have a bit of a darker colored "skin" in some cases. I had a set of exh manifolds for my Z16 ceramic coated in grey, then painted them Chev orange as proper. Hopefully, as the orange burns off over most of the body, they'll reveal the grey and stay that way.

Dave

[Charley Lillard]

Dave...For those of us who are now going out to look for Phosphoric and Nitric acids.... Where to get ? Dangers ? Did time suggestions ? Containers ? Disposal ? Shelf life ? Can we all send you our stuff ?

[JChlupsa]

What ever you do make sure you request a Material Safety Data Sheet (MSDS) when you buy any of the products. Stores are required by law to provide you with one upon request!! Dont just let them tell you that the small 1 paragraph wording on the side of the can is good enough. Its not!!!!!

[SS427]

[ QUOTE ]
Same process as Ricks only I use the green scotchbrite pad with warm water and dishwashing liquid.

[/ QUOTE ]

Good point Charley and one I forgot to point out. When using the Scotchbrite pad, you create a little aluminum dust and if you do not use the water/soap rinse, you just end up smearing all around. The water helps remove it. The hotter the better.

[Mr70]

I do this technique,but prefer to use COLD water.
Using the Warmer water seems to make the material more Malleable,& smears it around to much.
I also have had the Green scotchbrite pad colorize the manifold a little.I switched to the less abrasive WHITE scotchbrite pad,and use more elbow grease.
Just my experiences.

[CamarosRus]

I have NOT tried the below myself, but read this elsewhere on net......

"A mixture of Chromic Acid and water will clean most aluminum surfaces up really well if used correctly. It will also help to protect the aluminum from corrosion too. Go to a chemical supply house and buy some Chromium Trioxide Chrystals. When mixing, ALWAYS PUT ACID INTO WATER and NOT the other way around! Be sure to wear eye protection such as goggles and protective clothing of rubber or plastic when mixing any acid solutions together. Then put 7.5 fluid ounces of water into a beaker and carefully pour in .4 ounces of Chromium Trioxide Chrystals while stirring with a wooden stick or glass rod. This solution can be used on freshly machined aluminum surfaces or to treat mild corrosion. For areas of heavy corrosion, take a piece of plastic (plexiglass) and scrape the excess corrosion off and not damage the areas that are not corroded. The surface areas must be clean and free of oil or dirt before applying the solution. This solution mixture has a shelf life of about 30 days. Be sure not to dip in dirty cloths or dirty cotton balls into the solution repeatably as the removed corrosion absorbed in these will have a tendancy to kill the power of the fresh solution. When applying the solution onto the aluminum, allow the acid to stand for about 2 to 5 minutes or until it has stopped working (or bubbling), wash off with clear cool water to remove remaining acid and dry with an air hose or wipe clean with a clean cloth until dry."

Chuck S

[CamarosRus]

Dave from Iowa, If you look at the M-21 Tailhousing in above pics....I had that "TUMBLED" in Aluminum media, for a relatively short time. The media looks like pyramid shaped 1/2" Dia Alumninum pieces????. I also had ORIGINAL (not the newer design polished) LT-1 valve covers done the same way.
I WONT say they are "DEAD-NUTS" factory the same, but I gotta tell you they look as good as it gets.......I used a LIGHT glass beading first to remove any misc blemishes...
Chuck S

[CamarosRus]

Bill S, THE same Jeff Betz,indeed. He recently sold his WORLDS BEST 77' Z-28 & extremely impressive 02' Z-28.....and as you said changed direction with an older Chevelle 2 Dr wagon. I've seen pics of NEW 502/502 and Tremec 5-spd. Stand by for further details.....I stayed at Jeff's home during Woodward Ave dream cruise....
Chuck S

[MosportGreen66]

The intake on the Coupe was in good condition to begin with. Mild media blasting... then steel wool and WD40 cleaned it up real nice... The process has held up as well.

[P.J.]

Phosphoric acid and Nitric acid dip is the best nothing cleans aluminum better. I used it in the manufactoring of aircraft tooling for years. You can find a local aluminum
treatment company and ask if they will dip it for you.Those chemicals
are to be handled by pros and with the right equipment. Sand blasting your intake is not recomended as it is like adding sand in your gas tank use glass.
Peter

[olredalert]

Chuck,

-------The wagon is a 69, therefore not a 2-door. It is one of the cleanest 69 Chevelles I have ever come aross, and will make a hell of a family "truckster". Cant wait to see the final outcome.
-------Are you planning a return engagement at Woodward?..........Bill S

[hugger_69]

A buddy and I restored an original set of 69 Z covers just last Sunday and here is what we did to them. A light media blast with some real fine glass (worn out), then cut them with Triple 0 Steel Wool under the wash brush in a Varsol Bin. They were then washed down with Brake Clean and here is the end result. They look pretty darn close the factory finish if you ask me?

http://www.x33d80.com/images/Mechanical/Valve_Covers/Valve2.jpg

Graeme

[Salvatore]

Look good but I think to aluminum looking. I have an original non-dripper set on my car and they do still look original. I don't remember aluminum valve covers having a real uniform lookin sheen as the NOS ones do today. Intakes and valve covers are not supposed to look like they were touched. JMO. Old saying is.... whatever blows your dress up! Sam

[NCGuy68]

[ QUOTE ]
Phosphoric acid and Nitric acid dip is the best nothing cleans aluminum better. I used it in the manufactoring of aircraft tooling for years. You can find a local aluminum
treatment company and ask if they will dip it for you.Those chemicals
are to be handled by pros and with the right equipment. Sand blasting your intake is not recomended as it is like adding sand in your gas tank use glass.
Peter

[/ QUOTE ]

I agree, but use plastic media for blasting rather then glass or sand.

NOW...once you have that cast aluminium part looking OEM, how do you preserve the finish?

[fpcopo]

Chuck you are on the right track. All the guys (Don Dorfman, Jerry MacNeish, John the Vette injection guy in PA)that have done this in the past and do it now seem to get the same results. Dorfman started it and called it reskinning. I've had good results by cleaning the manifold really good then bead blasting it with fresh medium glass beads.After this go over it lightly with 000 steel wool. Then clean it with brake clean to get rid of all the steel wool. This burnishes it slightly and puts that nice "as cast" finish on the part. Flying "A" has a ceramic coating business next door now and Jerry Janing and I were talking about trying a manifold in their vibratory polisher to see what it would do. That manifold Chuck did looks really good and if a Wheelabrator did it maybe that is the way to go. I have often thought that the highly secret "reskinning" process was a little bit of bullshit to keep us from trying this on our own. Now as to the Edelbrock, they beadblast all their freshly cast intakes and then do the machining. To duplicate that finish you must really clean the crap out of the part and then blast it with new beads. The only drawback to this type of finish is it stains really badly and is hard to clean. If we try the vibratory polisher and it works I'll let you know. Frank http://www.yenko.net/ubbthreads/images/graemlins/BelairSucks.gif

[427TJ]

[ QUOTE ]
I have often thought that the highly secret "reskinning" process was a little bit of bullshit to keep us from trying this on our own.

[/ QUOTE ]

http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[Belair62]

Tell us what you REALLY think Frank...aka The Original Sausage http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

[Charley Lillard]

Snausages...... http://www.yenko.net/attachments/111292-P1010008.JPG

[Belair62]

I think Frank was saying "nuttin but a big ja$off"

[RichSchmidt]

I had the intake on my race car cleaned at a machine shop.They used some kind of method that made it lok like it was Jet Hot coated.I think it was the tumble method described in the other posts.I wanted to polish parts of mine and clearcoat it as soon as it was done being cleaned,so I bought a can of carb cleaner and some engine clear coat.As it turned out,the carb cleaner smeared the finish a bit,so I didnt use it aside from on 1 of the runners.My real plan was to put a light shine on the tops of all the runners using 1000 grit paper,then clean it with carb cleaner and clear coat it.After I got it back from the machine shop,I polished the tops of the runners,and used the carb cleaner on one runner and thats when the trouble occured.I cleaned the rest with a damp cloth,then clear coated the intake.It looks very nice,and if I hadnt polshed the runners,it would have looks like an as cast intake with clearcoat on it.
Before I had it blasted,I tried carb cleaner as well as wheel magic cleaner and neither would brighten up the 20 year old Strip Dominator intake,and te machine shop shine was absolutly the best way to go.I am attanching a few pics.If you look closely,you can see that the cylinder heads and carb spacer are as cast while the intake is slightly brighter.Late model aluminum parts do have a somehwat more deep finish then original old castings did back in the day,but the comparison is still pretty accruate.

[RichSchmidt]

And another

[RichSchmidt]

One more

[mrrec]

Charlie:
Don't send me anything - I have enough trouble getting my own stuff done!

I don't have a good source for the acids. Believe it or not, I had a bunch of that stuff that was in a building I bought years ago. It is nasty, nasty stuff though, as others have said. Noxious fumes and all.

I also have a drum of stuff (techno speak for I don't know what it is) that I bought at an alum foundry auction. It was presumably used for cleaning freshly cast parts and has some detergent-type properties and may be mildy acidic (the tip - it's in a plastic drum). It will brighten aluminum a little, too.

As for storage and disposal, call the EPA and OSHA and invite them over to see your chemical collection. I'm sure they'll want to see your checkbook, too. Really, the acids don't lend themselves to non-industrial use. I'd follow the advice of a post above and find someone who will dip it for you.

I know many have procedures they like and are happy with. More power to you.

Dave

[John Brown]

For years I've been cleaning aluminum intakes and transmissions with scotchbrite and bathroom tub and tile cleaners that contain weak phosphoric acid. I think aluma-prep does too. Just did a net search on phosphoric/nitric dip and came up with information on "electropolishing". Do the search on electropolishing, then call someone in your area that does anodizing. They may have some of the answers you're looking for.