Aluminum Anodes

[J_Papi]

I know all outdrives have approx 4 of these anodes. my question is what is there purpose and how important is it that they are properly grounded?<br /><br />Jeff

 

[Trent]

Re: Aluminum Anodes

Your anodes are to protect the drive from corrosion. Sacrificial anodes conduct the electrical current in the water and destroy themselves instead of your outdrive. In saltwater they destroy themselves pretty quick and need to be replaced regular. NEVER paint them or they cannot work. Its very important to be grounded and all the outdrives continuity wires (looks like small stainless steel cable)are present and connected.<br /><br />There mainly are two different types of sacrificial anodes...Zinc (most popular) and magnesisum.

 

[coupedeville]

Re: Aluminum Anodes

When you have ferrous and non-ferrous metals (steel & aluminum in this case) in water, it sets up an electrical current between the two, and this current dissolves the aluminum and transfers it to the steel parts. This is pretty much how electro-plating (chrome, or gold, or silver plating or anodizing) works, except you supply extra electrical current to speed it up. End result: Your expensive aluminum bits rot away. If you run straight water in the cooling system of your car (most engines these days have iron blocks and aluminum heads) you'll get the same effect. Bad news all around.<br />If you are boating in fresh water, you MUST use magnesium anodes, zincs won't do the job.

 

[SeaNile]

Re: Aluminum Anodes

Can you use pencil zincs in the iron block or will the drive anode be enough? Are the ppencil zincs for V-drives without a zinc on the outside?