Aluminium anodes

[sealine]

Hi all
Merrt christmas to you all.

I have been told that aluminium anodes are better than zinc?
what do you guys think?

 

[nonitoo]

Have a look at http://www.mgduff.co.uk/leisure-craft/cathodic-protection.html for info.

Tom

 

[whisper]

Zincsmart told me a similar thing - they last slightly longer.
Certain types/sizes are also slightly cheaper than the zinc versions.

We've put "ali" ones on our trimtabs as a trial. Bought ones twice the size of the previous zincs yet they were still lighter in weight. Wonder how they are getting on - we'll find out in Jan.

 

[tinkicker0]

AFAIK all OEM anodes fitted to Mercruiser drives are now aluminium, whether destined for salt water or fresh water.
For freshwater use though, I have a 4" magnesium donut anode on the transom for belt and braces protection. This is pitted after one season, but will last another.
Happily this has protected the drive and the ally drive anodes too! The drive anodes are not even pitted, just discoloured. Bonus!.

 

[johndove]

I will stick to the normal anodes as spec. Prices should drop this year as raw materials prices drop.

Save a few £££s and risks 1000s of £££££££££££££££



If they appear to be lasting longer , just maybee you outdrives or props might be waisting away, or your skin fittings, strentube, rudder, shfts!!!!

 

[Geoffs]

Here, here. I've been told Stainless steel blocks last for ever /forums/images/graemlins/laugh.gif

(you'll notice I didn't say anodes!!!!)

 

[tinkicker0]

No I just took the paint down to bare metal for repainting. No corrosion at all.

As I said, the magnesium anode had "protected the DRIVE and the less reactive aluminium DRIVE ANODES".

The drive anodes fitted are specified for salt and freshwater use and I trust Mercruiser know more about anodes than I, so Original Equipment anodes it is.

However the one magnesium anode had taken the hit for all the rest, so no replacement drive anodes required this year.
Redid all the electrical bonding last year, so if a bad connection has formed, then it may take out the drive anodes this year.

Nowhere did I say the drive was unprotected.

http://www-alt.mercurymarine.com/mnetdata/Service/Cruiser/Bullet/02/02_06.pdf

 

[Geoffs]

I never have any trouble with anode wasting, mine are three years old!