pkarczmar
06-18-2009, 07:58 AM
When we bought our 1968 Mariner 40 ketch it came with 2 pairs of zincs on the iron keel, a pair on the rudder, and one on the prop. I've changed them religiously twice a year. As I was going through zincs pretty quickly, I installed a galvanic isolator since we were hooked up to shore power and I thought that stray current may ber playing a role. This did slow down the zinc degradation. Nevertheless, I see a lot of paint pitting near the sites of the zincs and have noticed delignification of the wood where the prop shaft enters the engine compartment, indicating ongoing galvanic issues. I've had two folks tell me recently that the boat is "over-zinked" and that wooden boats don't need any zincs at all. Anyone have any opinions about this?