escknx wrote:Q1: what is the purpose of a wire conductor with green insulation that is near the fuel tank of an OUTRAGE 18 [of unspecified year] but not connected to anything?
With the wire not connected to the fuel tank, there is at present no purpose to that wire. However, in the original configuration of the boat, the green wire had a very important purpose:
The large-gauge wire, which will typically be 10-AWG size, is a BONDING CONDUCTOR that is part of the FUEL SYSTEM BONDING CIRCUIT.
Don SSDD wrote:[The unconnected green wire seen in Figure 1]...needs to be connected to a ground such as the battery negative.
Because we do not know what model year boat you are asking about, the recommendation that the bonding circuit should be connected to the battery negative terminal is probably INCORRECT, and you should not follow that advice, at least not until we get more information from you about the age of the boat.
As for why or how the green conductor near the fuel tank is not connected at this moment, I can offer only speculation that it became loose from vibration, or possible was intentionally disconnected for some unknown reason or by due to mistake.
FUEL BONDING CIRCUIT ON BOSTON WHALER BOATS c.1980 to c.1990
In most c.1980 through c.1990 Boston Whaler boats with an aluminum fuel tank, all the metallic elements of the fuel system had 10-AWG wire with green insulation connected to them, namely:
- the fuel filler inlet fitting on the deck
- the fuel tank vent fitting on the hull
- the aluminum fuel tank
These circuit elements were then connected to an electrode on the outboard face of the transom located below the waterline. The green conductor to the electrode typically was run down the transom face and retained by a clamp, then passed through the transom well above the waterline. The size of the electrode is about the size of a half-dollar coin, and the electrode is made from bronze.
In the OEM installation, this circuit was NEVER connected to the boat's battery negative terminal, nor should it be. The purpose of the circuit was to maintain all the metal parts of the fuel system at the same voltage. The reason for the desire to maintain all metal parts of the fuel system at the same voltage is to prevent a change in their voltage, which would create the possibility of an electric arc or sparking during fueling.
Because the fuel is gasoline, and because gasoline is an extreme NON-conductor of electricity, and because the fuel hoses connecting these metal elements were rubber, and because rubber is also an extreme NON-conductor of electricity, and because of the
triboelectic effect, it is possible for electric voltage to be generated by the flow of gasoline through rubber fuel hoses.
The reason the bonding circuit should NOT be connected to the battery negative is to avoid the possibility of any electrical current flowing on the bonding circuit. As in all bonding circuits (or "ground" circuits) the presence of a flow of current indicates a FAULT has occurred. For this reason, the bonding circuit is kept completely isolated from the boat battery.
Q2: on the outboard face of the transom of your OUTRAGE 18 of unknown model year, is there an electrode fastened to the transom and also to a green 10-AWG conductor that then runs up the transom and through the transom?
Also, in Figure 1, I see what looks like a short piece of rubber hose that is connecting a metal fuel line to the fuel tank at what may be the fuel pickup outlet. From this I infer that perhaps the fuel line to the engine or to an in-line fuel filter was a copper fuel line. Use of a copper fuel line is occasionally seen on the rigging of some Boston Whaler boat fuel system.