TARNISHED ENGINE
 

Is there a way to renew the aluminum on a tarnished engine, other than the crockpot method. I have several engines that are dark, maybe from too much crockpot/anti-freeze. I was thinking of tarnish remover for silverware. Thanks in advance for your comments. Dave I've tried Brasso, used it in the Marine Corps, and it removed tarnish but appears to be unsuited for the problem.

RE: TARNISHED ENGINE
 

A brass brush on a dremel does a good job, as do a lot of oven cleaners but with the oven cleaners , you have to be careful about how long you leave them.

RE: TARNISHED ENGINE
 

Stay away from the oven cleaners, I have observed some real messes.........

RE: TARNISHED ENGINE
 

I agree with him, the oven cleaners has acid and eating aluminium at your engine.

Jens Eirik

RE: TARNISHED ENGINE
 

Thanks for the responses...anybody else got any ideas. Dave

RE: TARNISHED ENGINE
 

Actually, the oven cleaners have caustic (alkali) rather than an acid. Unfortunately, strong alkali will attack aluminum just about as well as a strong acid. Does a good job on the castor goop but will (at the very least) tarnish or even ruin the aluminum casting with enough contact time..

Ross

RE: TARNISHED ENGINE
 

Years ago I had a really cruddy VECO 35. I had a friend who had access to a glass-bead blaster at work. I disassembled the engine and gave him the alloy parts. When he returned the parts they were beautiful. It is still a good looking engine to this day.[8D]....RJ

RE: TARNISHED ENGINE
 

Anybody try any of the aluminim polishes such as Flitz.

RE: TARNISHED ENGINE
 

Polishes have abrasives that will harm moving parts if not thjroughly cleaned out afterwards.
The bead blasting works well IF DONE RIGHT, it will actually "peen" the metal which hardens the surface of the metal a little.....be sure to tape off the surfaces that you do not want blasted such a machine cut mateing surface.

RE: TARNISHED ENGINE
 

I know about the benefits of glass beading. I used to race sports cars long, long ago and we magnifluxed (looking for cracks) shotpeaned, and balanced the crank and rods. Where can this glass peaning be done, I have no clue. Still trying to find a chemical solution to the problem. Is oven cleaner OK if you go very slow and watch closely. Thanks Dave

RE: TARNISHED ENGINE
 

Tucker:

Any discoloration can be polished off an aluminum casting. But unless the casting was shiny to begin with, it looks odd until you polish the entire engine. If the engine came with a dull finish a bead blaster will serve, if used with care. You will find a bead blaster tank at many auto repair shops, just be sure it is loaded with glass beads, the same tank will work as a sand blaster too, the sand is way too rough.

In heavy trucking the more weight you can fremove from the rolling stock, the more weight of freight you can carry. In this quest most modern trailers have aluminum skins on their bodies, and keeping them shiny was a problem, so they were usually painted. Until some smart fellow found how to keep them shiny with a chemical cleaner. This chemical cleaner is a very mild solution of hydrochloric acid. Go to or call your local truck stop, ask if they have the chemical wash for aluminum trailers. You might be able to bum a pint or so of their mix. It's not expensive if they want to charge you, and either way it's easier than getting reagent HCl and mixing your own. Be sure to use rubber gloves, and take care. The acid is mild but it will still give your hands a sunburn if you're careless.

The acid wash will restore the original finish, shiny will be shiny, and a matte finish will still be dull.

Bill.

RE: TARNISHED ENGINE
 

Tucker:

An addendum to the last post. The acid cleaner is ONLY for aluminum. If your part is either magnesium of zinc, or any form of "Pot metal," the acid will destroy it.

Bill.

RE: TARNISHED ENGINE
 

William...As always you come through...Thanks alot Dave

RE: TARNISHED ENGINE
 

William....I found out by looking up HCl in a google search "chrome removal" that muratic acid is a commercially available form of diluted HCl. I have some experience with muratic acid from my contractor days (cleaning concrete etc.) but remember that I once mixed a dilute solution in an aluminum pan and when I picked it up the bottom of the pan was gone. Can muratic be used in very small concentration. Dave

RE: TARNISHED ENGINE
 

I bought a couple of the Flitz products at a local home show three years ago. The demo looked pretty kewl as the salesman shined up some beer cans.

After a season of flying, I had some junk cooked onto the muffler and some oxidation on the Jett BSE engine crankcase, and I wanted to clean them up a bit for display at Toledo. So here I am, two days before the show with this 'seasoned' engine. Having been installed in the aeroworks Edge (inside of a cowl) I rarely took note of what was happening to the engine as far as varnish and corrosion and stuff. It was ok in general, but it definately needed some cleaning to be show-worthy.

I started off with a dremel polishing wheel and compound on the muffler. It did an ok job removing some of the varnish. Kinda dulled the surface finish more than anything.

Then I tried the Flitz just using a toothbrush and rag on the engine crankcase. Boy did that shine the bar stock case !!

Then I used the Flitz on the muffler... first by hand...then with the small buffing wheel on the muffler. I applied it, and let it sit on the part for about 20 minutes. Not only did it get the small bit of remaining varnish off, it shined the daylights out of the aluminum muffler! One last final touch up with a soft cloth by hand, and it looked like a mirror.

I had the BSE-1.00 with the turbo-jett muffler on display in the Jett booth at Toledo. Most folks thought the engine was brand new. There were amazed when I told them it was engine S/N 3 and had nearly 100 flights on it.

Not only did this stuff clean the oxidation and crud off of the engine, it KEPT it that way! Seemed to provide a bit of a sealant/coating action that prevented the oxidation and varnish from coming back.

I used both the Flitz cream polish, and also the gun polish. The gun polish was a bit "thinner" and apparently has more of a wax base to it. That may be why it kept the finish for quite a while.

Bob

RE: TARNISHED ENGINE
 

Bob..Thanks for your reply. William....So far in my search for truck products, I'm supposed to meet a guy in about an hour that sells to truck and body shops. He is from a outfit called Auto Magic and has a couple of products....Alum Brite and Spoke #66. Also called a plating service and he said to bring the engines by and maybe he could help. I'll let you know when I find something. Still need your reply on the muratic acid. Thanks Dave

RE: TARNISHED ENGINE
 

Tucker:

Muriatic acid is, as you said, the commercial grade of hydrochloric acid. Muriatic acid is sold for fluxing solder joints as well as cleaning mortar from bricks before they are reused. You can buy it from a plumbing supply as "Soldering acid," or from your buidling supply storefor masonry cleaning.

For cleaning aluminum it is usually sprayed on, the acid content is neutralized in its action but there should be a post rinse anyway. The reation is HCl+AlO -> Al+H2O+Cl (Didn't try to balance the equation, please excuse). The free chlorine product says do it only in a well ventilated place. If the reaction is allowed to run too long, or if the acid is too strong, you get aluminum chloride, and the bottom removed from your pan.

The reaction with zinc (any "Pot" metal) is much more energetic. HCl+Zn -> ZnCl + H, leaving us with a Zinc Chloride solution and free hydrogen. If you do this one, the ZnCl solution is a good soldering flux all by itself.

Check with your AutoMagic salesman about concentrations.

Bill.

RE: TARNISHED ENGINE
 

William...Just got back from meeting with the Auto Magic salesman. Supposed to meet him at a body shop across town. When I got there he had just left...said over the phone that the stuff costs 17.00 a gallon. I asked the body shop people if they had ever bought any alum cleaner from this guy and they went and got two kinds, one in a spray bottle marked "do not use" but it was non acid based "Auto Magic" on the label and a gallon of "Spoke #66", acid base. I asked if I could try it and got a bucket of water. It seems to work pretty good. I asked if I could get some in a small bottle and they gave me both and said I could have them, a gallon of the acid and a large spray bottle of the Auto Magic. BTW the first guy I called (truck detailer)was real nice but said he would not sell me any or give me any. I guess he thought I was a terrorist or a lawyer. He turned me on the to the Auto Magic guy. I will report back after I have had a chance to try this stuff out. I found a great web site for cleaning aluminum, posted by a motorcycle guy who has researched all the methods, you might want to check it out.....www.team.net/sol/tech/clean_al.html. William...thanks so much for your input and all the rest of you guys. This research keeps the juices flowing and I appreciate your help. I will get back to this tomorrow Dave