Since the EPA was taken over by overzealous crusaders top to bottom is has become nearly impossible to send a cast iron block out for cleaning prior to rebuilding.
So I am forced to do the 1275 Midget block myself.
First I stripped it, then I removed as most of the oil, old grease, crud, gasket residue and such with a scraper, wire brush, and mineral oil.
Now I have gone over it with my soda blaster, inside and out.
That removed all the old paint and gasket residue.
But this really does nothing for internal oil passages or water jacket rust.
So my next step is a bath in caustic soda (Lye).
I will follow that with an electrolysis bath to try to remove rust from the water jackets.
I will update this thread as I make progress.
