tach wire

[DAN M VAGOS]

hi all i have a 1987 mercury 700 70 hp and there is a plug on the mercontrol for the tach how can i get it to work i have a tach with pol setings on the back i know one is power one is ground but where to put the tach. thanks dan

 

[DRIFTER_016]

Re: tach wire

There should be 3 connections on the back of the tach. I,G and S I=12 volt ign power, G=ground -12 volts and S=signal (tach signal from engine)

The wiring should be as follows for Merc of that vintage I=purple, G=brown and S=grey

 

[Chris1956]

Re: tach wire

Dan, Ground is always a black wire. The other colors are correct. purple is +12V and Grey is tach signal.