Freshwater Anode Magnesium

Daron

.
May 7, 2019
3
Hunter H27 LKN
Hi, my 82 Hunter 27 with a yanmar 1gm is on a freshwater lake in NC. Does anyone have ideas to use a magnesium anode for this engine. I read that zinc is not really effective for freshwater. Any ideas or advice??
 

dLj

.
Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
That is what is recommended for fresh water. You are on the right path.

dj
 

Daron

.
May 7, 2019
3
Hunter H27 LKN
Thanks for the reply. It does not look like Yanmar or boatzincs.com makes a magnesium anode for the 1gm. Anybody make a diy magnesium anode??
 
Jun 21, 2007
2,105
Hunter Cherubini 36_80-82 Sausalito / San Francisco Bay
Just to clarify. Are you asking about the anode that actually mounts onto the engine? Or about the anode that mounts to the prop shaft?

Firstly, a disclaimer. I am not an expert on this topic.

If the engine does require a anode in lake water, it is probably a large diameter pencil zinc that screws into the mounting plug. This will be a generic item. Not necessarily Yanmar specific.

As this is a "every engine", question, rather than "Yanmar specific", maybe to go to the local ski boat engine repair maintenance shop and ask their opinion. Or call up these folks:

https://www.boatzincs.com/engine-magnesium.html

Marine grade aluminum anodes are also approved for fresh (lake) water. Likely likely would be able to locate one.

Lastly if your 1GM engine is anti-freeze cooled, rather than raw lake water, an engine anode definitely is not necessary.