How to Wire an OMC Gauge
- 1). Place a small flat-head screwdriver edge into the selector switch on the back of the tachometer. Very carefully and lightly press the switch in and turn it to the appropriate setting that matches the amount of poles in your alternator. If you do not know the amount of poles in your boat's alternator, you can look at the chart in the resources link below labeled "Outboard Tachometer Application. Be careful when pressing the selector switch so you do not ruin the tachometer. Also, be sure to set the correct setting on your tachometer gauge.
- 2). Find a location that you would like the OMC gauge to be installed at in your boat. It is preferable to have the gauge mounted along side your other measuring instruments for ease of accessibility.
- 3). Cut a hole into the dashboard of the boat using a rotary tool. Cut the hole corresponding to the gauges size. Place the back-clamp within the dash and secure it into place with the supplied hardware.
- 4). Cut a piece of 18 AWG wire and strip the end of it. Wrap the wire around the "BAT," or battery stud, and place a nut and lock-washer on the stud afterward to secure the wire in place. Strip the other end of the wire and route it a 12 volt power supply that is operational, while your boat engine is on. Look in your boat's manual to see the specific wiring diagram. Wrap the other end of the wire into the positive terminal that you choose.
- 5). Cut a piece of 18 AWG wire and strip the other end of it. Wrap the wire around the "SIG" or signal stud on the gauge. Place a nut and lock-washer on the stud after the wire to secure it into place. Strip the other end of the wire and connect it to a terminal or wire on the unrectified side of the alternator. This can be found in the boat's control box.
- 6). Cut a piece of 18 AWG wire and strip the end of it. Route it to the "GND" or ground stud on the gauge and wrap the wire around it. Place a nut and lock-washer in front of the wire to secure it. Strip the other end of the wire and route it to the ground on the boat. There are many different areas that you can hook a ground to near the instrument panel of your boat. See your boat's specific manual to locate a grounding area.
- 7). Place the blade terminal of the gauges light to the positive terminal of the boat's lighting circuit. See your boat's manual to determine the appropriate lighting diagram. You have now successfully installed a tachometer on your boat.
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