My recollection from some years ago is that it was on the port side of the heat
exchanger. This was on an engine that had a "V-drive" so the heat exchanger was
on the forward side, above the flywheel. The zinc was a "pencil" that from the
outside looked like a brass hex bolt, maybe 5/8 inch. When I found it with no
zinc left (after owning the boat a few years) I was freaked and pulled the
endcap off looking for pieces, but found none. After that I checked the zinc
every year.

BTW, I recently pulled out the heat exchangers on my 5 year old Yanmars and
found both were partially clogged with eel grass - the engines run a much cooler
now!


"Jon Klapper" wrote in message
...

Stupid Manual!!!! It says to replace the zinc in the heat exchanger
every year. The $#!!$ thing probably hasn't been replaced in ten years
and I can't find it. The box of junk and odd parts that came with the
boat have two different size bronze plugs with zinc rods cast into
them. They obviously screw in somewhere but I'll be damned if I can
find them. One old plug with a corroded zinc has a bit of red paint on
it and looks like its on the outside somewhere. Is it possible its
inside the heat exchanger? Should I pull the endcap?? Should I just
sink the damned boat and collect the insurance?

Anybody got a clue????