Some of my mates have used molasses before with excellent results. This is the first time i have tried it so it is in the experimental stage. There is a lot of info on the web about using molasses but i have not read a straight answer as to why it works... lots of theories (such as as it ferments it becomes acetic acid/vinegar) but no answers. I think people like to use it as it is cheap and easily available.
Thanks for the diesel advice and i am confident i can find a penetrating oil with a bit of a search.