what is the best way to get that yellow stuff out of my water jacket. How did you guys do it?

 

I'd use CLR personally. Most of the **** inside the waterjackets are, well should be, water deposites like lime and calcium etc.
Either that or soak the whole housing/iron whatever it is in varsol and start scrubbin.

 

or don't bother. won't have any adverse affects on cooling unless it is a thick shell.

 

Modified coolant flush!
Oh wait, we're talking about engine in pieces.
Hot tank it!


-Ted