1978 Johnson 150 hp tach wire

[NozonePike]

I'm looking to hook up a tach on my 1978 Johnson 150 hp. I keep reading about a grey wire. This is a V6 motor and has two control boxes. Any help is appreciated.

 

[alldodge]

Moved to Johnson, maybe get some other eyes on it

 

[racerone]

There are 2 powerpacks on the motor.-----Look into the control box at the helm.-----Might find a gray wire there.-----The factory tachometer operates with alternator pulses.

 

[saltchuckmatt]

Post a picture of your control boxes.

 

[racerone]

I think he is referring to the 2 powerpacks as " control boxes "

 

[saltchuckmatt]

I think he is referring to the 2 powerpacks as " control boxes "

Yeah maybe....I'll wait for a response before anymore advice. Just wondering if he knows you route through the control box (remote).

Thanks for clarification....had me stumped.

 

[NozonePike]

Post a picture of your control boxes.

 

[NozonePike]

Post a picture of your control boxes.

 

[racerone]

That control box may have a feature where you plug in a tachometer.---Post picture of area below the key switch.

 

[NozonePike]

That control box may have a feature where you plug in a tachometer.---Post picture of area below the key switch.

control box pic above

 

[racerone]

Well ---I can see the " picture " but I can't see whether it has an unmolested plug in for the tachometer.-----If you post a clear picture of below the ignition switch, I could tell you if it has that feature.-----Your boat is too far away for me to examine it.

 

[saltchuckmatt]

There should be a round runner cap below the key switch. If you pull on it you will see another rubber fitting with 3 wires connection. That's your tach tie in.

 

[NozonePike]

Well ---I can see the " picture " but I can't see whether it has an unmolested plug in for the tachometer.-----If you post a clear picture of below the ignition switch, I could tell you if it has that feature.-----Your boat is too far away for me to examine it.

 

[NozonePike]

I appreciate all the help from everyone. Thank you.

 

[saltchuckmatt]

Key switch, friction screw, rubber cap over rubber 3 wire plug. Pull on round black rubber cap revealing what's underneath.

 

[racerone]

Pull off the cap with letters and 5 on it.-----Easy to get answers when you post correct information !

 

[NozonePike]

Key switch, friction screw, rubber cap over rubber 3 wire plug. Pull on round black rubber cap revealing what's underneath.

I had a spare shifter and noticed it had a harness on it at that plug. Do you know what wires go to what? Purple, grey, and black.

 

[NozonePike]

Pull off the cap with letters and 5 on it.-----Easy to get answers when you post correct information !

I try hard, but at 72 years old, it's not as easy as it used to be.

 

[saltchuckmatt]

That plugs in to the spot we are talking about and those go back to the motor. Should be blue, green and red

 

[saltchuckmatt]

This rubber plug, should be easy....even at 72