At Port of Sidney out on G-dock, we went 12 or more months between changing our zincs.
Here are what the zincs look like when new:
Here are our zincs after 3 months at Fisherman's Wharf:
The split in half zinc (it is supposed to be split, it is a cuff style) is only 4 months old. This is normal for a lot of people and a lot of boats but our boat is very electrical neutral (or at least has been so in the past) and we have had great luck with low galvanic corrosion. Our zincs get eaten enough that we know they are working but not so quickly that we are afraid for our boat.
I'm glad we are leaving here in a few weeks. At least I know that our fresh zincs won't be consumed before we leave and the nice thing about anchoring is less stray current to worry about.
Ouch! That is serious.
ReplyDeleteWOW! I wonder if the water in the inner harbour might also be more acidic. There was a lot of heavy industry in the area years ago and who knows what leaked into the soil and now finds its way into the harbour!
ReplyDeleteIt's not just the marina - our zinc has doubled its lifetime since we got a new neighbor.
ReplyDelete@Carol & Lance - That's a great point.
ReplyDelete@Bob - True as well and we have floating homes and pleasure craft and fishing vessels near us so who knows.
Check the zinc(s) in your engines heat exchanger! If the outdrive zinc has deteriorated quickly it may have also effected the zinc(s) in the engine's heat exchanger. One of the more nefarious aspects of the disintegration of the heat exchanger zinc it that the eroding zinc bits will clog up the circulation tubes in the exchanger.
ReplyDeleteI found your site via the Interview with a Cruiser project, and have enjoyed reading both of your sites.
Good luck with your travels and keep posting.
Jeff
http://sv-cestlavie.blogspot.com/
A guy at my marina hauled his 34' power boat after only a month in the water because he was having steering problems...both rudders (brass I believe) were eaten down to little nubs and the metal shaft struts for both props were gone! He had installed some new electrical goodies and not grounded them properly....thats gonna hurt!
ReplyDelete@Jeff - We actually don't have any in-engine zincs.
ReplyDelete@Brett - yikes! I saw some photos of an eaten up prop shaft on someone's blog. I forget which now.