The Wages of Zin(c)
The Yanmar 1GM10 is the simplest of diesel engines, and mostly it just works. Its natural reliability can lead one down the path of negligence, however, and so it has been for me with regard to the zinc that is embedded in the cooling channels of the engine block. The engine block has a zinc anode because it is raw-sea-water cooled, and because this water is frequently salt water, the potential for electrolysis within the engine block is substantial. The problem is that this zinc is hard to get to, requiring moving the alternator out of the way so as to get a wrench or a socket near the bolts that hold the zinc-bearing plate in the block. Having done so, the plate comes off easily enough, and I had the zinc and necessary gaskets on hand. My intentions were good, you see... I've had these parts for two years, knowing that it had almost certainly been too long since the zinc was last renewed. The evidence: Nothing left. Not the smallest remnant of zi...