TACH NOT WORKING

[Bones 1]

WHEN I TURN MY IGNITION ON, THE NEEDLE DOES RISE AND THEN FALL DOWN TO ZERO SO I ASUME I HAVE POWER TO THE GUAGE<br />WHEN ENGINE RUNNING THERE IS NO READING FROM THE TACH<br />WHERE SHOULD I START TO LOOK . ALL WIRES

SEEM TO BE TIGHT FROM THE COIL<br />I HAVE A MERC OUTBOARD 135 BLACK MAX 1987

 

[Barnacle_Bill]

Re: TACH NOT WORKING

Signal for the tach is a gray wire that comes from your rectifier. Check your rectifier. Easiest way is to check the voltage at the battery, then start the motor. You should see a slight increase in voltage at idle. If you have the boat in the water, you can increase the RPMs and see if it increases more. If no increase, change the rectifier.