# Tach install on 2001 Merc 2stroke 40



## LSURed (Mar 28, 2021)

Hey guys, curious to see if anyone has any suggestions. Bought a new prop and want to check out RPMs, so decided to install a tachometer.

This is a tiller, electric start/ electric choke. So there's no wiring harness coming from a control box. All the instructions have the GRAY send wire for the tach coming out of that harness. Looking at the wiring diagram for my motor, it looks to me like the gray wire coming out of the voltage regulator is the correct send wire for the tach.

Tapped that wire to the tach, and then give it power and ground and I don't have anything registering on the tach. The light comes on (when it has power), but the needle won't register anything. 

I'm getting a reading of about 7-8volts when I put a meter on that gray send wire, both at the source as well as the tach.

Anyone have any suggestions? Obviously I don't have much experience with this stuff, but like to tinker.

Below: gray wire (send wire?) Coming from voltage regulator.









Below: wires at tach. I know connections are ugly, just trying to test before install!


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