Tach on 73 Mercury 500

[knouse94]

Ok, I have read every forum on here about this topic I just want some clarification. All I have the do is ground the tach anywhere, power the tach to ignition, and run a wire from the yellow wire on the stator to the sender on the tach. I have tried this and it does not work. I am wondering if my tach does not work. I have it set to 12 pole and it lights up with the ignition but does not pick up the motor. The needle is stuck at 1000. I purchased it used so I may have just been lied to about its condition. Opinions? Directions? Thank You

 

[Art Bernard]

Re: Tach on 73 Mercury 500




These pics are not merc, but might give you a general idea. I didn't draw them so all credit to the artist

Art

 

[knouse94]

Re: Tach on 73 Mercury 500

I am not using the harness that plugs into the control box. I am trying to wire it from the motor. Thank You

 

[ONERCBOATER]

Re: Tach on 73 Mercury 500

tack must be wired before the rectifier. then apply your other wires (gnd, lights, power) and enjoy. if you try to run from after rectifier it will not function. when energized even w/o engine running tach should go to ZERO not 1000....1000 seems to be where tach drifts w/o power.

hope this helps.... i had a post in about this a while back and they schooled me on it.

 

[knouse94]

Re: Tach on 73 Mercury 500

Ok guys I am an idiot I had the positive and negative hooked up wrong the take works fine now. Thank you for your input it helped me realize my problem.