In article h5Prh.9534$Wz.6778@trndny06, gordon
wrote:

On my Westerbeke 4-108, there is a zink in the heat exchanger and that
is it.

check your heat exchanger.

Typically, you only need zincs on the Seawater side of any Marine Engine
Cooling System. If you are Raw Water Cooled, in a Single Loop System,
then you would find zinc's in the Block, Exhaust Manifold Water Jacket,
and Overboard Thru-Hull. For any Dual Loop Systems, you would look at
the Raw Water side of the Heat Exchanger, and the Overboard Thru-Hull.
For a Keel Cooled System, you would only find them on the external
Keel Coolers.

Bruce in alaska
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