Cleaning Small Aluminum Parts of Oxidation

The aluminum parts on our project M20 after 66 odd years have developed a very hard dark gray oxidized coating.  I had some rust dissolver from a company in the U. S. Called Eastwood, which has been effective for rust removal. The label said it was safe for aluminum, copper, brass, rubber, seals, wood or vinyl. It also removes bluing and oxide coatings. 

So I gave the oxidized aluminum a 24 hour soak. When I pulled it out the next day the dark gray coating was still there but it had taken on a dull powdery look. Using a small bronze brush the coating came off easily and the aluminum looked liked it was freshly cast. A 3M abrasive pad also worked well. The picture shows a cleaned 276 carburetto body and the not yet cleaned float bowl and cap. in the states, Iím sure there is equivalent rust dissolvers in Europe,  just make sure it is safe for aluminum. 

Mike and Joe Rosson,  M20 #39662