G'day Ian et al,
Well, I just had to try it.
For the first test I had two identical engines (Honda Gxx) both had been subjected to flood water at the same time some years ago and were literally FULL of water when I got them home. I filled the first one to the brim with kerosene/oil mix. This was 6 weeks ago. The other I didn't do anything with until this weekend just gone when I tried the magic brew.
I had been gently working the kero oil machine over the past weeks and it finally freed up last Wednesday (5 and a half weeks). The ATF machine had freed up in a few hours!!
The other one I've tried is using it to free up a stubborn exhaust joint at work. For this we normally get out the Wurths Rost off. It's the best we've found for this. The ATF mix attempt took no time at all!
I'm not suggesting this is conclusive proof- far from it - but it is compelling and I will be trying it more.
I do have a couple of questions and observations however.
1. Why acetone? Would ATF and kero work just as well?
2. In hot weather will the acetone evaporate too quickly leaving just ATF? Your from Townsville, Ian, how do you find it?
3. I'm a little wary of getting the mix on enamel or acrylic paint as the acetone will soften it?
But all in all, I'm excited! For my next investigation the Hondas that I freed up are both attached to similar ride-ons (yes, dear readers, they're Geenies

) both of which are v rusty and both of which will be dismantled. One has been given WD40 to soak in and the other the brew. I'll let y'all know how it goes.
Thanks for the tip Ian.
Cheers,