Westerbeke 9.0 BCG Technical Manual page 167

Zinc Anodes
A zinc anode, or pencil, is located in the sea water cooling circuit within the heat exchanger. The purpose
of the zinc anode is to sacrifice itself to electrolysis action taking place in the sea water cooling circuit, there-
by reducing the effects of electrolysis on other components of the system. The condition of the zinc anode
should be checked monthly and the anode cleaned or replaced, as required. Spare anodes should be car-
ried on board.
If the zinc pencil needs replacement, hold the hex boss into which the zinc pencil is threaded with a
wrench while loosening the anode with another wrench. This prevents the hex boss from possibly tear-
ing off the exchanger shell. After removing the zinc, note the condition of it. If the zinc is in poor condition,
there are probably a lot of zinc flakes within the exchanger. Remove the end of the heat exchanger and clean
the inside of all zinc debri. Always have a spare heat exchanger end gasket in case the present one be-
comes damaged when removing the end cover. Replace the gasket (refer to your engine model's heat
exchanger end gasket part number), cover, and install a new zinc pencil.
NEW
ANODE
REPLACE REPLACE
161
CLEAN
OR
REPLACE
Westerbeke Generators