Merc Bravo 3 Anodes... Aluminum?

[KetchiMan]

So, I found a service bulletin from Merc stating that Alpha, Bravo 1 and Bravo 2 have all changed materials from Zinc to Aluminum Alloy. Does this apply to Bravo 3 as well? I can't find a service bulletin for the Bravo 3. Did this service bulletin come out before the Bravo 3 did?

Is there any possible advantage to zinc or is aluminum alloy 100% the way to go?

Thanks.

 

[Scott Danforth]

Re: Merc Bravo 3 Anodes... Aluminum?

zinc is more sacrificial than aluminum on the galvanic scale, however zinc is more expensive than aluminum. I personally would want zinc so that the anode disappears faster than the outdrive that is made of aluminum.

http://www.engineersedge.com/galvanic_capatability.htm

 

[TilliamWe]

Re: Merc Bravo 3 Anodes... Aluminum?

But if you boat in saltwater, you'll want the aluminum ones. I doubt any others would last long enough. Certainly not the magnesium "freshwater only" anodes!

 

[Don S]

Re: Merc Bravo 3 Anodes... Aluminum?

Having lived in Ketchikan myself, I can say for sure he boats in salt water.
The Mercruiser Aluminum is what you want. The only reason the Bravo III wasn't mentioned in the 91 service bulletin is because it wasn't invented yet.