When starting your project, make sure you have wires, crimp terminals, and all tools right near your work area.

The electrical system of your boat is its lifeline. Every system on the boat depends on it, including the engine, yet it is often neglected or its importance is underestimated. You need reliable gauges and wiring to monitor engine operating status and other vital information. Since your wiring is the only link between your gauges and engine, faulty wiring could cost you a lot more than just an afternoon and a spool of wiring.  We enlisted the help of Marine 2000 located in Long Island, New York to assist us in illustrating proper marine wiring techniques.

Your boat’s electrical system is responsible for monitoring engine function, delivering proper signals and inputs to the engine, and powering onboard accessories. Although average marine electrical systems tend to be much less complex than automotive systems, they must endure significantly more harsh environments.

Moisture, corrosion, extreme vibrations, and temperature extremes are the norm for the electrical system of your boat. For this reason, there are specific products and rigging techniques that should be used to allow your boat’s electrical system to remain reliable and safe for many years. If you just purchased a used boat, it might be a good idea to thoroughly inspect its wiring. A complete wiring project can be accomplished in one weekend on most boats, and the materials are not expensive. The following article will outline common techniques and materials that are used to properly wire a boat

Terminal distribution blocks allow easy access to battery power.  From here, wiring will enter fuse blocks up front.

For marine use, wiring a boat with common copper wire is a common mistake, and should be avoided. Copper wire strands oxidize very quickly, and the common byproduct of that oxidation is a green layer of oxidized metal, which will eventually degrade the conductive connection to a terminal, and ultimately fail. Always use a marine-grade “tinned” wire. The use of tin in the wire stands prevents corrosion, while increasing conductivity. Never use single-strand or “solid core” wiring. Vibrations will cause the wire to break inside the insulation, creating all kinds of intermittent electrical problems.

Plastic-jacketed crimp terminals should work fine for most purposes, however, we recommend the use of high quality “bare” crimp terminals, and adhesive lined heat shrink tubing is highly recommended. The heat shrink tubing slides over the base of the crimp terminal and wire, shrinking when heat is applied from a small butane torch. The shrink wrap is lined with heat-activated adhesive, and will seal the wire insulation to the crimped on terminal, providing more water resistance as well as strength to the terminal. While most shops and riggers use common plastic-insulated crimp terminals, the outer plastic shell provides very little protection against corrosion.

Page Two: Terminal Crimping The Right Way