the winter I placed a pair of Brake Drums off my 1969 Mustang and left
them to soak. Truth be told, I forgot about them and after a few months
of soaking, they came out pretty clean. There was some crusty rust remaining
in the tight places where it had been built up thick.
I think they could have stood some brushing to help the process along,
but regardless, the molasses did eat nearly all of the rust, and I'm
sure many of you know how much rust can build up on a set up drums!
The container I used was a plastic tub approximately 3 feet by 1.5 feet
by about 10 inches deep. I filled it up as much as I could while still
allowing th ecover to fit over the top if held down with a weight. The
smell was not offensive even though at least an inch of mold grew on
the surface of the molasses.
I neglected to take pictures of the drums before and after their treatment,
but I can come up with another set from the front of the car which shold
give a good idea of before and after. They will also provide a good
reference for effectiveness if I am able to properly document the process.