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Motor Anodes

Mar 26, 2017
Irwin 38 Palacios
Hello All,
I recently had my 1985 citation pulled out for repair. While it was out I changed the shaft anode and the bracket anode.
My question is do most motors have a "pencil" anode inserted in the motor? I have a Yamamar diesel in my boat and have inspected all the parts I can see without pulling cabinetry apart but see no anode "plug."
Do I need one, or is the shaft and bracket protection enough??
Nov 6, 2006
Hunter 34 Mandeville Louisiana
The 3GM series Yanmars do not have anodes on the fresh water cooled engines..If you have a Yanmar of the mid '80's, with a heat exchanger, it probably does not have anodes.
EDIT: If the engine does not have a heat exchanger, it will have anodes, 3; one on the aft end of the cylinder head, and 2, in the block, under the exhaust manifold. They are bigger than the pencil ones; about 1" in diameter with a large hex head.
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