Some phosphoric acid is eating the salts out of the cooling system in the manifold. Most holes were completely clogged: advice get fresh water cooling with a heat exchanger, though the holes in the heat exchanger are smaller than those in the engine and they can also get clogged! Tough choice!
Hard to see on this picture but the water that made its way through the head gasket had pitted the metal (bottom left). The top of the piston was also pitted and a grove can be felt in the cylinder
Cork gasket material cut for the sump gasket.
Head and manfold reassembled and painted, etc
little Shala next door cooked us some pancakes!
(cracktested the head, cut new gaskets, acid cleaned the salts from the
cooling system: never chose RAW cooling!), using the yacht decks as workshop
benches, the parts did not look like they would arrive early enough so a new
Bukh is going to replace the old one, flown out of Sydney tonight
(argh!!!!). That's the price of deadlines!!!
All up, it was a great mechanical course and the new "Bukh" is exactly the
same as the old one, so it's great to know how to pull it apart- just in
case!