Olive Drab paint removal

[oldsport]

What is the recommended method to remove the original Harley Davidson factory applied olive drab paint form the cast aluminum engine cases of a 1942 WLA 45, with out harming the aluminum nor the various pressed in bearings and bushings? Do you know if this paint was lead based enamel or lacquer or maybe a water based paint? It was does not seem to be a durable paint, in some areas I can remove it with a finger nail. I do not plan to repaint these cases as they are being used in a civilian model WLD 45. I have not been able to locate the correct 1940 WLD 45" engine cases. This original lower engine unit was replaced long before I obtained this bike. Back when military surplus was available and cheaper than dirt.

I have heard several suggestion for doing this...all conflicting.
Thank you for your time and efforts.

Oldsport

 

[NDT]

Lead based. I would throw it in the bead blast cabinet.

 

[clinto]

As NDT said, it's a lead enamel.

It doesn't stick to the aluminum not because it's a bad paint, but probably because the surface was not prepped properly and the correct aluminum specific primer wasn't used. Aluminum requires a specific (zinc based I think) primer in order for it to adhere.

If the case is completely disassembled, I would just throw it in the cabinet.

If you aren't fully disassembling it, I'd blast it with dry-ice* or use a chemical stripper.

* like this: http://en.wikipedia.org/wiki/Dry-ice_blasting

 

[Whiterabbit]

Chemical stripper then a pressure wash.
I use "aircraft" stripper from the parts store, takes it right off. It'll even remove the silver paint honda uses on their engine cases!