Westerbeke 12.5 BTDA - Zinc Anode Function and Replacement; Heat Exchanger Service Procedure; Air Intake Silencer Maintenance

COOLING SYSTEM
Zinc Anode
A zinc anode, or pencil, is located in the raw water cooling
circuit within the heat exchanger. The purpose of having the
zinc anode is to sacrifice itself to electrolysis action taking
place in the raw water cooling circuit, thereby reducing the
effects of electrolysis on other components of the system.
The condition of the zinc should be checked monthly to
det~rmine its service life. Once that is established, the zinc
replacement period can be noted in your maintenru;tce log.
Spare zinc anodes should be carried on board.
NEW
REPLACE REPLACE
ZINC ANODES
ClEAN AND
REUSE
NOTE: Electrolysis action is the result of each particular
installation and vessel location; not that of the engine.
If the zinc anodes need replacement, hold the hex boss into
which the zinc anode is threaded with a wrench while loos-
ening the anode with another wrench. This prevents the hex
b~ss from possibly tearing 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 debris. Always have a spare heat
exchanger end gasket in case the present one becomes dam-
aged when removing the end cover. Replace the gasket (refer
to your engine model's heat exchanger end gasket part num-
ber), 0-ring and cover, and install a new zinc anode.
NOTE: The, threads of the zinc anodes are pipe threads and
do .not require sealant. Sealant should not be used as it may
insulate the zinc from the metal of the heat exchanger hous-
ing preventing electrolysis action on the zinc.
Heat Exchanger Service
After approximately 1000 hours of operation, remove; clean
and pressure test the engine's heat exchanger. (A local auto-
motive radiator shop should be able to clean and test the heat
exchanger.)
NOTE: Operating in silty and/or tropical waters may require
that a heat exchanger cleaning be performed more often than
every 1 ooo· hours.
AIR INTAKE SILENCER·
AIR INTAKE SILENCER
The function of the air intake silencer is to reduce the
pulsat~ng air intake noise produced by a diesel engine while
operatmg.
Th~ air intak~ silen~er has no filter element inside. The only
mamtenance It reqUires is that the inlet opening be kept clear
of
any obstructions to air flow into the silencer.
Engines & Generators
. 16 .
AIR INTAKE
SILENCER