Mixing hull and engine anode materials

[MichaelB1969]

Hi everyone, I have a Beneteau Swift Trawler 44. Does anyone know if it is okay to use Aluminum anodes on the hull, and Zinc for the Volvo engine pencil anodes?

I do have a new set of Aluminum anodes for the hull that I may put on, but the Zinc pencil anodes are brand new, so wondering if I can keep them in there or not.

I thought I read somewhere that you could mix in this case whereas typically it's a no-no.

Thanks much!
Mike

 

[kchace]

Yes it's ok. Thy are protecting different electrical "areas".

Ken

 

[REAL MOUNTIE]

I don't know if this applies to your bonding system situation... And I do not want to disagree with Kchace, as there are two different electrical areas.

Here is an article on the matter as an example about the more active anode (aluminum) will spend part of its effort protecting the less active metal (zinc). This will reduce the overall protection that you are getting. A classic mistake is adding a zinc transom anode to a Sterndrive equipped with aluminum anodes. Transom anodes are connected through the bonding system so make sure you install aluminum replacements.

Also Defender recommends NEVER MIX Zinc and Aluminum Anodes on the same vessel.

Sources:
http://www.performancemetals.com/images/pdfs/Aluminum Anodes.pdf
How to Choose a Zinc for your Boat

 

[psneeld]

Pencil zinc in engine and aluminum anodes on exterior of hull OK...or vice vetsa OK.

 

[MichaelB1969]

Thanks for the replies. Appreciate it. I did buy aluminum pencil anodes for the Volvos but now I don't have to put them in there until the zinc pencils are ready to be swapped out.

 

[IRENE]

Thanks for the replies. Appreciate it. I did buy aluminum pencil anodes for the Volvos but now I don't have to put them in there until the zinc pencils are ready to be swapped out.

I found the zincs in my D4 to waste much faster than I anticipated. Just FYI sir.

Jeff

 

[MichaelB1969]

I found the zincs in my D4 to waste much faster than I anticipated. Just FYI sir.

Jeff

Thanks Jeff. Yeah, they were definitely in need of replacement when we got the boat down here. But not sure exactly when the prior owners switched them out. Will definitely keep a close eye, thanks!