You can use aluminum anodes in fresh water. That's what I use. They're cheaper than magnesium.
To test for stray currents, borrow a clamp on ammeter. Then check the AC line supply for your boat, and for the boats in nearby slips. The ammeter should read zero amps. Use the lowest scale, as stray currents could be pretty low. If the reading isn't zero, some of the current is finding a return path, other than through the AC supply line. Alan Bergen 35 Mk III Thirsty Rose City YC Portland, OR On Thu, Aug 9, 2018 at 6:01 AM, Mike Taylor via CnC-List < cnc-list@cnc-list.com> wrote: > Hi Bob > > I started the season with 1.5 anodes. I’m in fresh water, Lake Ontario and > St. Lawrence river. I believe I have the correct anodes for fresh water. I > really don’t want to go the galvanic isolator route > > Mike > > On Aug 9, 2018, at 12:04 AM, Robert Boyer via CnC-List < > cnc-list@cnc-list.com> wrote: > > What is the condition of your shaft zincs? > > Are you in fresh water or salt water & do you have the correct zincs for > the type of water your boats in? > > Sounds like you may need a galvanic isolator... > > Bob > > Bob Boyer > S/V Rainy Days (1983 C&C Landfall 38 - Hull #230) > Blog: dainyrays.blogspot.com > <https://urldefense.proofpoint.com/v2/url?u=http-3A__dainyrays.blogspot.com&d=DwMFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=9w3G7Cf8YfQnrjmtuNxwDJYr3JMv9f1pAfgAJ9xXYQQ&m=fJAQMdpX2dTSopdOWc3l9uX5S1WMFKlmsA86BrWxBCw&s=Wa3qqugmtpAwXVFKMv4mxeeuUh8qI-Q-QEkwBjxxvQo&e=> > Email: dainyr...@icloud.com > Annapolis, MD > > On Aug 8, 2018, at 8:10 PM, Persuasion37 via CnC-List < > cnc-list@cnc-list.com> wrote: > > > Hey folks > > I’m looking for some help. Persuasion is suffering from galvanic > corrosion or stray current corrosion or something. When I connect a multi > meter, ground to engine and positive lead to various place like keel bolt, > mast and through hull I see ~0.5V. Today I changed out the controller on > the wind generator, with the circuit breaker open I saw 2.4V on the battery > leads. Also the prop shaft was tarnished looking as well as the prop when > I hauled out to do the centre board. > > Before I call in the calvary can anyone advise me how to tackle this > methodically and what I should look for. > > > Thanks in advance > Mike > PERSUASION > C&C 37 *(k/cb) *shoal draft > Long Sault > > _______________________________________________ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > <https://urldefense.proofpoint.com/v2/url?u=https-3A__www.paypal.me_stumurray&d=DwMFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=9w3G7Cf8YfQnrjmtuNxwDJYr3JMv9f1pAfgAJ9xXYQQ&m=fJAQMdpX2dTSopdOWc3l9uX5S1WMFKlmsA86BrWxBCw&s=6TDTN3EQ7I80Q-k6fidTyrTJYYR_NiZP1etzSo1Nj8E&e=> > > _______________________________________________ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://www.paypal.me/stumurray > <https://urldefense.proofpoint.com/v2/url?u=https-3A__www.paypal.me_stumurray&d=DwMFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=9w3G7Cf8YfQnrjmtuNxwDJYr3JMv9f1pAfgAJ9xXYQQ&m=fJAQMdpX2dTSopdOWc3l9uX5S1WMFKlmsA86BrWxBCw&s=6TDTN3EQ7I80Q-k6fidTyrTJYYR_NiZP1etzSo1Nj8E&e=> > > > _______________________________________________ > > Thanks everyone for supporting this list with your contributions. Each > and every one is greatly appreciated. If you want to support the list - > use PayPal to send contribution -- https://urldefense.proofpoint. > com/v2/url?u=https-3A__www.paypal.me_stumurray&d=DwICAg&c= > clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r= > 9w3G7Cf8YfQnrjmtuNxwDJYr3JMv9f1pAfgAJ9xXYQQ&m= > fJAQMdpX2dTSopdOWc3l9uX5S1WMFKlmsA86BrWxBCw&s=6TDTN3EQ7I80Q- > k6fidTyrTJYYR_NiZP1etzSo1Nj8E&e= > > >
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