If you Google "rust removal by electrolysis" You'll find a fascinating list of sites on rust removal. The" old engines" guy even has a picture of a 1918 Chevrolet V8 Engine. I used Wash Soda and a battery charger to remove rust from a lot of healey parts, large- rear axels, and small- all those little bits that lay around rusting. It works great. Dave and Daisy