Originally Posted by
mudski
Personally I wouldn't be doing this. Imagine if it lets go when under full tension it would be just like a snatched towball would be. A deadly missile.
Remove the entire towbar, sit it upright with the tongue upwards and get some either hydrochloric acid, or phosphoric acid and pour it down inbetween the tongue and housing. Let it soak over night and try hitting with a sledgy or something. The acid will oxidise the rust. If you don't have those acids, you can use Coke, it also has phosphoric acid in it. Lol. And we drink this stuff. Albeit diluted...
I have both acids here if you need some. I live in Mill Park so...