Installation of a Marine Tachometer
- 1). Loosen the nut on the power terminal of an adjacent instrument, usually marked with a "plus" ("+") sign. Wrap the red power wire of the tachometer clockwise around the terminal and retighten the nut with a small adjustable wrench.
- 2). Loosen the nut on the light terminal of an adjacent instrument, which has another white wire attached to it. Wrap the white illumination wire of the tachometer clockwise around the terminal and retighten the nut.
- 3). Use a screwdriver to loosen one of the screw terminals on the boat's common ground. Wrap the tachometer's black wire clockwise around the screw and retighten the screw.
- 4). Route the data leads from the transmission sender to the back of the tachometer. Remove the nut in the center of the back of the tachometer and slip the ring terminal onto the end of one data lead over the terminal post. The sender data leads are not polarized, so they can be attached in any order. Thread the nut onto the post and tighten it with the adjustable wrench.
- 5). Remove the nut on the grounding terminal on the back of the tachometer and slip the ring terminal of the remaining data lead over the terminal post. Thread the nut onto the post and tighten it with the adjustable wrench.
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