Molasses

Oh, it probably does, to some extent anyway. Molasses has a number of identifiable acids in it, and probably a lot more that are not so easy to identify. So, this would be like soaking the rusted part in a weak acid solution...

It is a lot more effective, though possibly more expensive, to soak the part in a dedicated and optimized mineral scale removal product. Some of these work wonders, even in cold solutions, in a short period of time, and do not remove substantial amounts of the metallic iron....