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Ohm Test

Ohm TestStory and photography by Capt. Vince Daniello

If your boat is in the water, skip this step and spend a little more time on the next. But if she’s on the hard, connect an extra-long lead from a digital multimeter to your engine (or one of your engines) where the DC negative bus and your starter battery’s negative cables attach (note that, due to the limitations of studio photography, our photo shows this particular lead clipped to the top of the sea strainer). Now set the meter to read ohms and begin working your way around your boat, ensuring there is less than 1 ohm of resistance at each bonded fitting. Pay particular attention to your transom zinc(s), strut mounting bolts, trim tabs, rudder posts, and prop and rudder shaft logs.