A fusible link is a protective device used in an electrical circuit that acts very much like a standard fuse. The major difference is that fusible links are larger and capable of conducting a higher amperage than most fuses. When the current increases beyond the rated amperage for a given link, the fusible metal of the wire link will melt, thus breaking the electrical circuit and preventing further damage to any other components or wiring. Whenever a fusible link is melted because of a short circuit, correct the cause before installing a new one. There are four different gauge sizes commonly used and they are usually color coded so that they may be easily installed in their original positions.
REPLACING FUSIBLE LINKS
See Figure 1
- Disconnect the negative battery cable, followed by the positive cable.
- Locate the burned out link.
If both ends of the link are ring terminal connectors which are easily accessed:
- Measure the installed length necessary for the new link.
- Unbolt and remove the link and connector pieces.
- Obtain a suitable length of link, then strip the insulation off the harness wire back 1 / 2 in. (12.7mm) to allow soldering of the new connectors.
Position the new connector around the new link and crimp it securely. Then, solder the connection, using rosin core solder and sufficient heat to guarantee a good connection. Repeat for the remaining connection.
Whenever splicing a new wire, always bond the splice with rosin core solder, then cover with electrical tape. Using acid core solder may cause corrosion.
If the ends of the connector are not easily accessed, repair the length in the vehicle.
- Strip away the melted insulation and cut the burned link ends from the wire.
- Strip the wire back 1 / 2 in. (12.7mm) to allow soldering of the new link.
- Using a new fusible link of appropriate gauge and length, solder it into the circuit.
- Tape all exposed wiring with electrical tape and seal with silicone or use a heat shrink tube, if available, to weatherproof the repair.
- If removed from the vehicle, install the link and secure the connectors.
- Reconnect the positive, followed by the negative battery cables.