How to Change Battery Cable Ends

In a marine environment, the boat's battery and battery cable terminals are confined in the high-humidity environment inside the battery box. Because battery terminals are made from a different metal than the battery post to which they are attached, they face the same type of galvanic corrosion that a motor and boat suffers without zinc anodes for protection. This means that eventually, the terminal will require replacement, even if you use brass terminals. Always use a terminal the same size as the AWG wire gauge.

Things You'll Need

  • Adjustable wrench
  • Cable cutters
  • Cable stripping tool
  • Straight, barrel-type battery-cable terminal, 5/16-inch end nut
  • Straight, barrel-type battery-cable terminal 3/8-inch end nut
  • Propane torch
Show More

Instructions

    • 1

      Open the boat's battery box. Remove the cables from the battery posts, using an adjustable wrench to loosen the nuts. Lift the black, negative cable from the battery before you remove the red, positive cable. Remove both cables from the box. Close the battery box, trapping the cables outside of the box.

    • 2

      Cut the negative cable end from the negative battery cable by cutting the cable with cable cutters. Make the cut as close to the cable end -- the terminal -- as possible. Strip a half inch of insulation from the body of the cable using a cable stripping tool. Slip the shrink-type insulator, provided with the barrel-type terminal, over the end of the cable and slide it back on the cable, away from the stripped end.

    • 3

      Place the end of the terminal that fits over the battery post into a bench vise and tighten the vise to hold the terminal. Drop the slug of solder -- provided with the terminal -- into the tube-end of the terminal.

    • 4

      Heat the terminal with a propane torch, melting the slug of solder. Withdraw and shut down the torch. Push the stripped cable-end into the solder, so the cable's insulation is even with the end of the terminal.

    • 5

      Slide the shrink-type insulator over the terminal as far as it will go. The insulator will shrink around the junction between the cable and the terminal. Fit the 3/8-inch bolt and nut through the end of the positive terminal and the 5/16-inch bolt and nut through the end of the negative terminal.