ZINCS

[quill]

Having lived in 5 or 6 Marinas over the years I've noticed my engine zincs wear at a different rate at different Marinas. Currently they last 12-14 months. What are some of the factors contributing to fast or slow wear, and how do you check the Marinas shore power?

[Cap Erict3]

AC current flow in the hull, prop and rudder due to improper bonding of the neutral is the biggest culprit.

Testing the ground lead for AC current flow is an easy first step.

[quill]

So different rates of zinc deteriorate at different marinas would be a ground problem in the marina power? how can I check that?

[Cap Erict3]

A clamp on AC ammeter placed on your shore power cable (all conductors at once) will read 0 unless the current has another path. Current returning to the transformer through the water and ground connection will give a higher than zero reading.

Insulation breakdown in electrical equipment can be checked with a megohmmeter.