Galvanic Isolator report

[knotflying]

I put in a Galvanic Isolator in April 2012. I replaced all my Zincs. I use my prop zinc as my telltale. It is now March 4, 11 months since I installed it. I have been at a few marinas during last summer a few days here and a few days there, a week here and a week there. I have been cruising in Florida since January and have been in marinas a majority of the time. We pulled the boat this past Friday for a trip across state and I would say that my Prop zinc has held up much better this year. I estimate it is a little less than half gone and will be replaced along with all of the other zincs when we get home in April.
Mike Rizzo

 

[baz]

Mike: I did same thing last year and installed a GI. I have my underwater anodes checked every 3 months by a diver. I'm finding that the prop anode and thruster anodes are lasting twice as long. I'm very happy.

 

[Longbranch Louie]

If I am running the boat often enough to maintain the batteries would it be better on zincs to run a heater or dryer using an extention cord with a 30 amp adapter instead of plugging the boat into shore power while at the marina? Im not even sure if I can get a cord inside the cabin and still have everything secured but just wondered if keeping the boat off the grid would lessen corrosion/zinc eating enough to make it worth the hassle. Is electrical leakage from other boats and marina wiring more the culprit anyway? Lastly does having a solar panel keep current flowing adding to corrosion or is that different because its DC? As a new owner should I just be resolved that changing zincs is a part of boating and just enjoy?

 

[baz]

Much has been discussed on this subject over the years...

IMO replacing anodes is a fact of life with boating. Replacing them vs. not replacing them frequently is far more cost effective compared to the damage that can occur when the real metals start to erode. For example, If the thruster anodes aren't replaced when necessary much damage can occur with an associated large repair bill.

To answer your question... I would say it was better to run the extension cord... but letting the batteries discharge too much is not a good idea. Some marinas will not allow what you propose... my marina does not allow it.

No matter what you do, anodes will always erode over time. The effort many of us go to is to simply slow down the rate of erosion.