Inastalling tach on brand new 90hp johnson?

[Plank]

Wondering how to install my old tach to my new engine? Bought the system check gauge without the tach, already have a tach in the dash. Thanks

 

[seahorse5]

Re: Inastalling tach on brand new 90hp johnson?

The wiring harness from the engine has the plug connector for the back of the System Check gauge. There are also 3 wires, black, purple, and gray that are taped off and are used for a tach. Gray is the tach wire, purple is 12V positive, and black is ground.

 

[Plank]

Re: Inastalling tach on brand new 90hp johnson?

Thanks Seashore for the help. Do you know what setting the tach should be set on. My old engine setting was 6, dont know about the new one. Thanks