hooking up tach

[snowfeet]

just recently bought a new boat and it needs gauges. motor is a 1994 johnson oceanrunner 225 hp. when hooking up the tach wires, are they thru the main harness and what colors are they? any help would be greatly appreciated.also is there a port to hook up a water pressure gauge on the block?

 

[Joe Reeves]

Re: hooking up tach

Tomahawk..... The sender wire will be leading out of the engine/instrument wiring harness, and is GRAY in color. The other wires can be located either at the harness or elsewhere. The tachometer will (usually) have four wires and connect as follows:<br /><br />Tach "GRAY" to GRAY harness wire. (Sensor)<br />Tach "BLACK" to any associated ground. (Grd)<br />Tach "RED" to light switch. (Bulb in tach)<br />Tach "PURPLE" to 12 volt source when key is in the "ON" or "START" position only. (Power to tach)<br /><br />NOTE... Keep in mind that you definitely do not want 12 volts running to that tachometer when the key is "OFF".<br /><br />The tachometers operate off of the charging system on those engines which emits a six pulse signal to the tach. The OMC tachs have a dial on the back whereas you can set it for that pulse setup. Set the dial to number 6.