just got to taking the heads off the flathead I got a while back to inspect things and I am really happy with what I see. Cyliner walls look brand new, as do the pistons. Valves are older but seem to be really clean, and in great shape. Besides the dozen or so dead flies on top of one of the pistons (Im guessing that exhaust valve was maybe open and they decided that was a good place to die) My only concern is the water jackets...common area of concern on a flathead I figure. Is there a process to clean these at home without taking apart the entire motor for an acid bath? That brings me to my next question...if I take it in for a bath, it must be totally dissassembled, correct? Thanks for the info.