CORROSION SURVEY

A corrosion survey is a check of voltages derived with a silver/'silver chloride electrode and taken from each metal fitting on the boat (outdrive, seacocks, propeller, shaft, etc) to record the voltage. These voltages are compared to a chart to derive whether the fitting has enough sacrificial anode protection or too much. Voltages are compared with all instruments on and then taken again with them off. If there is a discrepancy, one instrument is turned on at a time until the culprit is found.

An accurate way to determine if you are using adequate (or too much) sacrificial zincs and a check to see if there is adequate electrical connection between the zinc and the metal you are trying to protect. Also checks for defective paths to ground from your electrical equipment aboard as discribed above. Can also discover problem boats near you causing electrolytic corrosion on your boat!

This survey is done as preventive maintenance to prevent corrosion problems and as a trouble-shooting tool if you are already experiencing problems with underwater corrosion.

This test could save your outdrive, or even worse, your boat! This is a complicated subject so don't hesitate to ask for more info.