Zinc anodes are used mostly in salt water applications to reduce the electrolysis effects between two dissimilar metals like your stainless steel propeller shaft and the bronze propeller.
The shaft zinc will usually be fitted to the boat’s shaft with a collar style design. Be sure the actual shaft metal is clean to make a good electrical conductive contact. There must be no dirt or paint between the two metals. And if you paint the shaft then DO NOT paint the zinc! The paint would reduce the effectiveness of the zinc through the water because the paint acts as a barrier or insulator.
In fresh water boating a different metal than zinc may be used, sometimes aluminum or magnesium.
What zincs do you have aboard your boat?
- trim tabs
- swim platform braces
- stabilizer shafts
- Where else? Consider the heat exchangers on your propulsion engines and generators. click here for an article that details this type of zinc.
Learn more about zinc installations and how you, the boat owner, can check them to see if they need replacing. Ask Captain Chris this and so much more at our seminar Introduction to Boat Systems. Learn more here about when and where you can attend our next program.