Heat exchanger

[JohnNorton]

Cleaning the heat exchanger tubes can be done with a wire coat hanger. The twists in the end (after you twist one apart) seem to fit exactly the small tubes in the exchanger. i removed both end caps, pushed thru (with some twisting) the coat hanger wire (could possibly use a correct gauge rifle cleaner as well) reaming out/ cleaning the tubes. I also found some broken pieces of the old zincs at the starboard end while i was at it. I don't see any buildup on the outside of the small tubes so I'm not going to mess with an acid wash. Boat runs at 162 deg at any RPM.