I am getting some corosion on my drives in fresh water. merc cathodes are working fine this is a dual drive set up with lots of stainless parts , props , hyd. steering etc. was wondering if having the drives powder coated with a clear on top of paint or have a clear coat sprayed on paint would help ?

the more paint the better. use magnesium instead of zincs.

Is your boat plugged into shore power?

yes, plugged into shore power .

I'ts possible you are getting stray current from something where you are tied up. The ground on the shore power completes the circut to whatever is causing the problem. There are isolators that break the DC circut on the ground wire, they can help.

Past this I don't know much more about it, but there are lots of articles online if you Google.

marc what are these isolators you talk about ? where can i get them and where are they mounted? do you sell them and what is cost ? thanks again

If you are plugged into shorepower then what you are looking for is a 'galvanic isolator' - google it.

ground isolation transformer.

There are a few other materials other than zinc that you can use for anodes, especially for fresh water. It's been talked about a few times on here. Magnesium is recommended IIRC.

Mercury makes one, it is part number 888557T01, we sell it for 341.52. I attached a PDF that explains it very well.

There is also a kit that includes the isolator and a monitor to tell you it is working, 888557Q01.

Guest & Pro Mariner also make one.

http://www.boatstuffexpress.com/p-16...vanic-iso.aspx