Does anyone have any good suggestions for removing oxidation on crankcases & gearboxes etc? And how do you keep it at bay?
Im not looking at bead blasting. Thanks Peter

Peter,
A dilute Phosphoric acid solution sprayed or brushed onto the affected area will remove the oxidation. if the affected part is powdery scrubbing with Stainless steel wool and this acid solution works well. I have found that spraying C R C or W D 40 onto the surface (after washing well in water) will keep the surface free of oxide. Aluminium is quite porous and will absorb quite a bit of this treatment. Repco and supercheap auto here in N Z sell Phosphoric acid as Preperation treatment for Auto paint ( K & H line ). Dulux used to have a product called Deoxidine 424 in 1 litre containers, your local Panel shopsupplier will sell you a similar product used in the refinishing industry. the thing to remember with aluminium is that oxide forms on it with exposure to the air and forms a "self protecting" layer or film which protects it from further atmospheric oxidation. Do not let it near Alkaline solutions (washing soda,or Caustic soda., also Carbon Tetrachloride with which it is highly reactive) and dont couple it to Copper if you want it to last. spraying with an oil such as CRC will keep the oxide from forming as will waxes or car body polishes
I hope this helps-Steve Hainsworth, Wellington N Z

Futher to my advice on removal of oxidation. If prior to this you want to clean and degrease said crancase or component a good method is to get a 44 gallon drom or similar sized vessel and place it on a gas ring -L P G fuelled. fill the drum deep enough to submerse the item , with hot water from your kitchen then bring to the boil and let simmer, add a suitable amount of washing up detergent and and immerse the offending part. the really hot water and detergent really eats into all that grime, a dash of phosphoric acid will help to shift the sh-t as well. This hot water bath is also- a much better and cleaner way of preheating crancases for bearing installation and removal-and heaps cheaper than an oil bath! cheers Steve H

Try cleaner stuff for alloy car wheels the type you spray on it is partially acidic also paraffin and wire wool all have helped me over the years