Yamaha tach install question with pictures

[flyinhuey]

Trying to wire the tach on a boat I just purchased. The tach was installed but not wired up. It is a 40hp Yamaha with side controls. (not sure on model #'s off hand, I can look them up if needed)

As you can see in the picture the tach has the wires for the lights (black and blue) and three wires for the analog tach. (black, green, yellow). The side throttle control has a few sets of pig tails coming out of it. One with the colors of the wires for the tilt/trim. The other with the wires i suspect to hook up the tach.(Red, White, Yellow, Green, Black) These are pictured in the second picture. I assumed it was as easy as matching up the colors but something isnt working.

Also there is a place to switch between 4, 6, 12 under a rubber grommet on the back of the tach. I have read this is to switch between poles. Any idea what setting I need to use?

Any guidance in the right direction is appreciated. I hate when something doesn't work right that seems so simple.

 

[rodbolt]

Re: Yamaha tach install question with pictures

from the control box, red is 12v battery power,not used on the tach.
yellow is key on 12v,used on the tach.
black is ground,green is tach send .
the white I have never seen from a 703 box.
but white is the kill circuit wire and not used on any gauge.
depending on the model of the 40 hp the tach setting is 4 pole,6 pole or 12 pole.
see why we ask for model numbers?

 

[flyinhuey]

Re: Yamaha tach install question with pictures

Thanks Rodbolt. The model is; 40PLRQ

From what I have read on the forum I figured those were the color wires I was looking for. Matches up with the wires on the tach.

When I connect those together I get nothing. I haven't put a voltmeter on it yet, but is when I do is there a way to test the tach signal (green) to make sure I have a signal coming in?

 

[flyinhuey]

Re: Yamaha tach install question with pictures

Put the voltmeter on it today. 12 volts on the yellow (key on) good ground and 12 volts from the tach wire (green). Still no reading on the analog tach. What is the voltage supposed to be off the green wire?

Bad tach? Any suggestions?

 

[99yam40]

Re: Yamaha tach install question with pictures

http://faria-instruments.com/site_manuals/IS0100_Tachometers.pdf
see if this will help you understand the tach signal

 

[flyinhuey]

Re: Yamaha tach install question with pictures

Thanks 99yam40,

Anyone know what pole setting my model engine should be set on?

 

[bradahut]

Re: Yamaha tach install question with pictures

from the control box, red is 12v battery power,not used on the tach.
yellow is key on 12v,used on the tach.
black is ground,green is tach send .
the white I have never seen from a 703 box.
but white is the kill circuit wire and not used on any gauge.
depending on the model of the 40 hp the tach setting is 4 pole,6 pole or 12 pole.
see why we ask for model numbers?

I also bought a Teleflex Tachometer and Trim Guage for a yahama 703 control but don't know the wiring code for the control. Help would be greatly apprecaited ps there's a black, red, green and yellow also 2 green wires together 2 Blue with red stripe together and 2 red together on the control