Case cleaning

Zeke · 02:01 PM

I would like to know the process for cleaning engine and tranny cases (aluminum) to concours condition. No stains, not polished, just totally original and bright.

rfoulds · rfoulds's Garage

Since the cases never had a finish, there really isn't an "original" condition, other than clean.
Once any metal oxidizes, all you can do is clean it and polish it.
Clean them up with degreaser or "no-heat" oven cleaner, and then, if you want a nice finish, give it a coat of mag polish. It won't get polished up nicely unless you use a polisher or a lot of elbow grease. But the mag polish will even up the metal color.

I tried putting high heat urethane spray on mine to keep it shiney, but it all burned right off.

Otto · 01-27-2002, 12:23 PM

Every engine case and transmission case gets put in our "HOT TANK". The hot tank is a 55 gallon drum of carburetor cleaner. Nasty stuff, but it gets the job done. One time I came into the shop in the morning and there was 50 gallons of carb cleaner all over the shop floor. What happend was that the carb cleaner ate a hole in the bottom of the hot tank and leaked all over the shop floor. You should see what carb cleaner does to tires!!!!!! I think my tire bill that day was about 3450.00..... After we get the cases out of the "HOT TANK" they go into the Safetykleen wash bin and are cleaned with solvent. Then we blow dry the cases with air and let them sit for a few hours in the sun. This gives the award winning finish that you concours freeks desire. If you check out the October 1992 issue of Excellence, a magazine about Porsche cars, you will find a picture taken by Bruce Anderson on page 58 of my Division winning concours 914/6 at the Porsche Parade in San Deigo in 1992. And all you out there thought I was just a racer. I also won the overall time/speed/distance Porsche Parade Rally in 1989 at Traverse City, MI. And you just thought I was a racer. I was at the POC awards banquet at the Peterson Museum in Los Angeles last night and all I got was a class win trophy. I was hoping for driver of the year, but not this time. I will be in their face in three classes next year. OTTO

Zeke · 01-27-2002, 02:13 PM

Not too sure about the oven cleaner as it as caustic and seems to darken the aluminum. I've read that hydrofluoric (not hydrocloric) acid really cleans, but HF acid is very, very dangerous and not easily obtained. Any other ideas? Thanks for your replies.

Otto · 01-27-2002, 03:38 PM

Where is Lonb Beach, CA. ???????? If you bring your stuff here we will do it for you... OTTO

neilca · 01-27-2002, 05:07 PM

You should not use a caustic on aluminum it will "smut" or darken the aluminum. You need to stick to acids. Try wheel cleaners for aluminum wheels whithout a coating. I have used Eagle Products wheel cleaner with good success. The tranny case is a different story, being magnesium. Corrosion is a constant problem particularly around salt (ocean air). Your best bet is to paint the transaxle. Try a silver with a clear coat.

Hope that helps,
neil