anode maintenance

[dvx216]

In all the years of boating I have never heard anyone talk about anodes except to replace them. During my 3 year boat inspection I ask the surveyor about the condition of my anodes and do they need changed. His answer gave me the a "Da" moment when he said as long as they are intact your good to go but if they are not clean they will not do what they are supposed to do . He told me to take a wire brush to them. They are in fact a electric sacrificial contact point and if they are corroded over they aren't as effective.

 

[OllieC]

I’d like to know if theres a process as well. I replaced mine when I went from salt to fresh water. The boat is also trailered. That was 8 years ago. The magnesium anodes look fine, not much pitting or reduction - the outdrive is clean. Inquiring minds want to know.

 

[Henry Boyd]

I rarely changed the anodes on our outboards. I would scuff the oxide off in the spring and until they really showed signs of deteriorating left them alone. But these also were able to come completely out of the water.

Once we moved up to the B3 you could practically see them evaporate.

 

[DWABoat]

I have read that if the anode is eaten away to half it’s original size, time to change. Once it gets less than half, your sacrificial material is getting less than specified by the manufacturer.
Of course, they were selling anodes...so consider the source.
Since the cost of failing anodes is a destroyed outdrive, and the anodes are relatively cheap and easy to change, I do it when I see significant decay.

 

[Ralph vaughn]

Great information on anode maintenance. Thanks for starting this thread.

ralph

 

[DWABoat]

I manage numerous boats in my job. Right now I am in the process of changing $15,000 worth of lower units where the bearing carriers were eaten away in less than 2 years. The corrosion prevention system was improperly designed by the manufacturer and the corrosion was hidden behind the propellers. Fortunately, the manufacturer is accepting responsibility.

I do not ever underestimate the power of chemistry.

 

[mratlndmrk]

So do you think I should change this?

 

[Henry Boyd]

So do you think I should change this?


View attachment 83223

Uh, oh yeah.

 

[duffman04]

So do you think I should change this?


View attachment 83223

It's still good! HA!

That can't be real.

 

[mratlndmrk]

That is the actual zinc on my shaft right now. The other side looks the same. Not sure how it didn't fall off. I'm doubling up this year on each shaft.

 

[DWABoat]

Tell me that anode is 5 years old, please.

 

[mratlndmrk]

Nope. New last spring.

 

[RBB]

Nope. New last spring.

Damn, glad I am in fresh water.

 

[duffman04]

Damn, glad I am in fresh water.

+1

 

[mratlndmrk]

Damn, glad I am in fresh water.

That's what it's there for.

 

[DWABoat]

Damn, I’m glad I’m on a trailer!!