tacho problem

[fluidjuice]

Tacho wired as per manuel grey to send , ground to black and ignition to red,
when ignition is turned on tacho needle drops to 0. batery shows 11.9 volts with multimeter when turned off on key and 14.80 volts when engine running so i am presuming regulator working and engine is charging battery ok. problem is tacho only works erraticly when boat is moving and then shows around 7000 rpm's when 5000-5500 is max ,but will not register the 650-700 rpm's at idle.This is a new teleflex tacho.

Mercury 40hp classic 1991 4 cylinder

 

[Chris1956]

Re: tacho problem

Check to see that the Tach is set to the correct number of poles for that merc. it should be identified in the Tach manual or on the Teleflex Website.
Next check to see that the tach sender connection to the rectifier or VR is clean and tight.

 

[janneman]

Re: tacho problem

got any further on this, fluidjuice?

seems you have a similar engine as i have (mariner - belgium build- 50 hp 2 stroke, 4 cylinder from 1986)