Aluminum engine anodes

LittleGidding

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I have a 315 hp Yanmar 6LYA with maybe 6 pencil zincs in the raw water circuit. I am at the very top of the Chesapeake, at the mouth of the Susquehanna River, so slightly brackish, very low salinity. I have replaced my bonding, thruster and prop anodes with aluminum, but the engine anodes are all zinc. Removing an older one recently I noted that it wasn’t consumed at all but rather had a weird thick crust on it making it larger than original, and difficult to remove from the engine. Till I bought it this winter boat was kept out of the water on a lift in Annapolis, further down the bay, still brackish but higher salinity.

I thought perhaps I should also change the engine anodes to aluminum, and found a source, but the caps are stainless, not bronze or brass. Problem?
 

Tunacious

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Most zincs are threaded into the bronze end cap. Have you tried to unscrew the aluminum anode and use the bronze end cap
 

ginger snap

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i believe that you can get them at zincs.com i have been getting my zincs there . if you spend 100.00 the shipping is free
len
 

PatriciaLynn

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Zincs are one of those simple, inexpensive things that protect the engine from catastrophic damage.

While there are plenty of people on here with a lot of experience and knowledge, ask your local Yanmar rep this question. They are the ones that will have to back up the product if the anodes don't protect the engine and they are the ones that have access to the official Yanmar recommendations.
 

TCL

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Getting back to the OP’s question, SS vs Brass plug? I’m really not sure. Brass is softer so might be less prone to leaking, I might be concerned that the SS plug being harder than brass could damage the treads on a heat exchanger if not installed correctly.

As far as should Aluminum anodes be used? I would try to reach out to a Yanmar dealer or Mack Boring to get there opinion. Since some of the heat exchangers have 2 anodes you could do 1 Aluminum and see how it looks at the end of the season.
 

TCL

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Yesterday I went to Bay Shore Marine Engines in Annapolis.
I asked if they had aluminum anodes for Yanmar engines. The parts guy said that Yanmar doesn’t offer them but they do have them available from another supplier. But did not have any in stock. He also said that they are a mix of metals, not pure aluminum.
 

LittleGidding

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Most of my engine and trans anodes are easy to check… guess I’ll just stay with zinc for now and keep an eye on them. I have aluminum on all the in-the-water locations this year (propeller, bow thruster, transom bonding anode). Will see how they fare comparatively.
 

Genius

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Brackish water, I wouldn't worry about it too much. Better things to be concerned with. I wouldn't use stainless plugs/zinc holder.
 


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