[FL&WVMIKE]

Dad and I attacked a torn down 21 stud with a 9 hp Pressure Washer and a long Screwdriver. The amount of sediment in the bottom rear was shocking. You could tell much of that had been there for decades. I don't see any kind of chemical flush and a garden hose doing much to the lion's share of it, but it probably can't hurt.

What I learned from that experience, is just how much crap can accumulate in one of these old flatheads, how important it is to use modern antifreeze, and keep them flushed the best you can in order to prevent a ton of sediment buildup. That, and when you do tear one down, go at it caveman style, with a strong pressure washer and a long screwdriver!

I liked the idea above, where a guy said he emptied his swimming pool through the engine! That was rich, creative and just might work! lol

Good Luck!