Aluminum anodes, been reading they are better than zinc?

They last longer than zinc
I found one, not my size
It is not just aluminum, it is alloyed.

MARTYR Aluminum Pencil Anode for Volvo, 838929
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I measured the opening on the HE and the plug it is 0.675 which is 3/8" NPT thread. What could be done is grind the larger aluminum anode diameter small enough to fit that hole. An interesting idea maybe, and would be easy to do, but I already have a replacement zinc for the HE. I am likely some day to try it, because these zinc anode pencil disappear faster than I like. Gone in a year.
 
The info I read is saying aluminum is better than zinc for saltwater. I know it is normal for zinc HE anodes to last maybe a year.
So far, I would have to modify one to fit.

It could be that anode makers want you to keep buying zinc anodes, if aluminum last longer, they make less money.

And that one I saw for a Caterpillar, according to the Martyr catalog is not aluminum, even though Amazon says it is aluminum.

Volvo has specified to use aluminum anodes in some engines, so they do make 2 part numbers in aluminum rod.
 
Did a search for "aluminum anodes better than zinc"

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As in most cases there are no absolutes. Setting aside the technical issues of why Al anodes could be considered "better"; there is a steep learning curve around how to leverage those advantages. So yes, the US Navy has moved to the weight and electrocapacity merits of doped aluminium anodes....by spending tens of thousands of dollars in research and analysis to ensure adequate protection where commerically you would slap on another zinc.
 
jehardiman said:
As in most cases there are no absolutes. Setting aside the technical issues of why Al anodes could be considered "better"; there is a steep learning curve around how to leverage those advantages. So yes, the US Navy has moved to the weight and electrocapacity merits of doped aluminium anodes....by spending tens of thousands of dollars in research and analysis to ensure adequate protection where commerically you would slap on another zinc.
Click to expand...
Martyr dopes aluminum anodes with something, it is not just aluminum.
All aluminum anodes like for sterndrives and outboards will be like that, designed to do the required job.

Sure the Navy has done their work too.

If you can get an aluminum boat anode, then IMO, that is a good idea.
 
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