Tach not working consistently

[tyler.woodard04]

2011 tracker pro guide 16 wt. 2012 60 HP EFI merc.  When the boat is off the tack stays up in the 1500 range. Running sometimes it seems to be right at idle other times it seems to read high. Usually when the throttle is maxed out it's showing well over 7000. I know that's not right. Anyone seen this before and have a solution? Be nice to have it working right. Thanks

[J.D.]

I have a 1996 90hp. Merc 2-stroke, my tach was also inconsistent.  On the back of my tach, there's a switch that rotates using a flat head screw driver. The numbers on the switch match the number of cylinders in the motor. My outboard is 3 cylinder, so my tach is set on #3. That way the same tach can be used on a number of different motors.  I rotated the switch back and forth a dozen times to clean off the contacts, finishing back on setting #3 and the tach returned to normal operation. This may not fix your problem, but it is the easiest thing to try first. 

[tyler.woodard04]

I'll give it a go thank you!

[Frogger]

My evinrude 115 was doing same thing, replaced rectifier. All better. From what I learned could be a slew of things. Contacts, like what was suggested, wiring connections etc. someone on here will have some other ideas to try or will have the answer for your particular motor. 

[tyler.woodard04]

Ok, got home from work and looked into this. Tried turning the dial and same thing. Pulled the tach and looked closed. Googled what the 60hp merc should be and found it needed to be on 6p. Not 4c.  Looks like it's working as it should now. Fingers crossed we will see in the morning. Thanks for the help