Posted: September 09 2006 at 14:10 | IP Logged

As your prop zinc deteorates faster than your transom zinc it indicates that the electrical connection between the transom zinc and engine block ( shaft ) is poor or broken. Normally a green wire connects all metal hull fittings together and to earth ground via your shore power cable. Check and clean all these connections. If you find your transom zinc begins to errode quickly after you have reestablished your grounds you my have a dock neghibor leaking current. I would suspect an old wood boat.

Trim tabs are not normally painted with antifouling paint and are generally cleaned monthly. Your rudder area may need paint. I'd wait untill the next haul out.