I would try a scrap piece of aluminium with the potassium permanganate before throwing your engine in it, I have a strong potassium permanganate solution I made up at work, I will see if I have something to try clean in it tomorrow, I'll tell you how it goes Bill.

If you get it on your hands it stains them brown and makes you look like someone who likes to smoke the herb, so watch out. Also it can be explosive if mixed with petrol or other hydrocarbons and I think that combination is shock sensitive to.

Here're the subjects A piece of ally tube covered with castor and cooked on over a gas stove till golden brown, and a heli muffler