94 omc 115hp tach wiring

[SKEETR]

The tach never worked, according to previous owner. Pulled the tach and found a lot of "other" wires running to it. Should a tach be used as a junction box? Probably fried huh? Was under the impression that only one wire should be going to each of the 4 terminals. There are 3 purple wires @ 12+, 3 black on the next over, one grey on the pulse. Two whites on the upper lug near dial. Dial is set correctly at 6.

 

[Reggie08]

Re: 94 omc 115hp tach wiring

I believe you can use "jumper wires" from the tach to run to other wires to supply power i.e. purple wire for +12v, black for ground, etc. As long as there is only 1 wire attached to "Signal" connection, I don't think it matters.

 

[ezeke]

Re: 94 omc 115hp tach wiring

I agree. The main thing is that when the ignition key is turned to the run position the tach should react by moving to zero. Both black and purple wires are correctly wired to the ignition switch. The gray sender wire should run to the terminal block on the engine to provide the signal. It is contained in most main harnesses.

The diagram towards the end of the following thread may help: http://continuouswave.com/whaler/reference/ignitionSwitch.html

Be very careful not to let any voltage ride the gray wire back to the engine or you will destroy your rectifier (or worse).