Cleaning for rebuild

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How do you clean the motors' aluminum to get that "like new" look? I'm Pretty good with the smooth surface parts such as the timing cover and the primary case cover. I just can't get the cylinder head and engine cases as clean as I would like.
 
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Cleaning Aluminum

Use the gentlest method that will give you the results you need.

Hot water and/or solvent and a brush is always my starting point, and that works on most surfaces with a smooth texture.

If that doesn't get me where I need to be, blasting is the only other option I have. Walnut shells are the media of choice; there are plastic media available, but I've not used them, maybe someone who has can weigh in on that?

DO NOT use glass beads on engine/trans internals. I know it's done sometimes, but IMO it's bad practice. The glass tends to imbed itself into the aluminum and then works it's way loose later on. Silica floating around in your oil is a bad thing.

Hope this helps!

T.C.
 
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Make certain everything is as clean as possible before you start. Lacquer thinner will do a good job of de-greasing. The cast (rough) parts clean up well blasting with glass beads. As T.C. says, stay away form internals. The smooth parts need to be buffed and polished. If they are in rough shape to begin with, start with some 220 grit sandpaper working your way down to 600 grit, then buff. Buffing is a dirty, time consuming job. So is blasting, for that matter. Both are best done outdoors. Don't do either one with out proper protection. Eyes, ears and nose need to be covered. If you can find someone to do both reasonably, by all means do so.
 
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Aluminum is relatively easy. Powerwash parts that are really cruddy, then degrease with petrol solvent and acetone, using a small brush. Once completely clean, use a pre-polish and a buffer, either table-mounted or hand-held. Get all the nicks and scrapes and discolorations out. Then do it some more. Then change to a fine-cut polish until it gleams. Do it some more, then some more, and some more. The more you do it, the shinier it gets.

Use wool pads if you can get them. Change the pads often. It seems to work better if you are working on individual disassembled parts. It works better if you can get friction heat built up on the part you're cleaning. I don't think the brands matter that much, just the effort you put in, but I'm sure there are those that will disagree.

Better yet, hire someone to do it, unless you have a lot more time than money. :)
 
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I bead blasted a timing cover to get the finish nice and even. Then I spent a few hours wet sanding. I decided to leave a few scratches as evidence of a life well spent. The advice about internals is good. There are horror stories about oil tanks and internals that continue to release "grit"
Patience will get you there 8)
 

Hortons Norton

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All of the above is good advice, I took my shiny stuff down and had it done by a shop that specializes in polishing. This was because it took me about 6 tubes of elbow grease on the first cover and the price was such I took the rest to him. Then on the cases they have a method of cleaning that uses a slurry of water and detergent under high pressure to clean, I have heard it works great. But I have never used it, Chuck.
 
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"I took my shiny stuff down and had it done by a shop that specializes in polishing."

Smart man!
 

JD

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Most machine shops will have a wash cabinet or hot tank that will clean your cases to look like new. I took the cases of my 76 Bonneville in and they got back looking factory fresh. It's surprisingly cheap, too. Save your elbows for holding the counter down at your local pub. Cheers!
JD
 
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" Save your elbows for holding the counter down at your local pub. Cheers! "

Now, here's someone who knows how to put his time to good use!
 
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Have a look at this site to get some more ideas:

http://www.machinerycleanery.com

These little brushes are very useful for cleaning rough cast surfaces which are difficult to access. You can make your own cheaply and I can describe my method if you want.

Scotchbrite abrasive pads, e.g. http://www.freemansupply.com/ScotchBriteIndustr.htm work very well. They come in grades from Ultra Fine to Coarse and you should be able to get them from a good engineering supplies shop. If you grip some of this material in a thin snipe-nose pliers, you can clean between the cylinder head fins and it works a treat. I found it helps to use some petrol or WD40 with the pads, and then wipe clean with a rag. ScotchBrite pads in Fine and Ultra Fine Grades also work well in removing deep oxidation on smooth surfaces, which is then followed by polishing.
 
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