Zinc Fish

[fstbttms]

Attaching a "fish" zinc to the shaft or engine is unlikely to provide any protection for the strut. The zinc must have direct electrical contact with the item in question to provide protection. The strut is probably not in direct electical contact with either the engine or the shaft. You could (as previously mentioned) attach it to the strut bolts, but what a PITA, IMHO.

Most likely, the current strut zinc has become passivated and/or has poor contact with the strut. I suggest cleaning the strut very well and installing a new zinc.

[unbusted67]

I just dove under the boat and inspected the strut, prop shaft, and steering column zincs and didn't notice anything wrong. I didn't see any corrosion on anything except for the zincs. It occurs to me that I am not familiar with the signs of galvanic corrosion under water. Is there something specifically that I need to be looking for under there?