Here's some links to get you started on electrolysis.
http://www.davidbradley.net/ERR.html
http://www.bhi.co.uk/hints/rust.htm
http://www.nothingtodo.org/projects/norust.htm
http://www.troycustomdetectors.com/s...ctrolysis.html

Art

"Andy Dingley" wrote in message
...
On 9 Sep 2004 14:17:09 -0700,
(nattydreadlocks) wrote:

can anyone tell me if potassium hydroxide is any good at removing
rust?

No, it's rubbish at it.

If you really need to remove rust from a cast iron block (rather than
oil, varnish, sludge, grot and the usual stuff) then look into
electrolysis.

NB - Make sure this block is a block, not an engine, and that's it's
all made of cast iron. A few bits of steel are OK, but one aluminium
casting left in place really isn't likely to survive most of the
cleaning processes.

--
Smert' spamionam