Once the part is clean, you can apply OsPho which is a physophoric acid to get rid of the rust.
Mike, you meant
phosphoric acid, right?
Jerry, cooking oil in a parts washer might work OK, but definitely not for parts that need to be painted. That yuk film that's on fryers would need to be removed, or paint would fall right off. And if Molasses is OK for cattle to eat, it doesn't have any disposal issues. There's a bottle of Molasses in our kitchen cupboard for baking uses. It's only a concern after it's eaten.
Evaporust is non-toxic and can be disposed of down the drain. Maybe it'll help derust some of the wastewater plant equipment.
