no volts on tach circuit

[bayprowler]

I have a 1987 Johnson 140. I just installed a new regulator/rectifier thinking that would cure my tach problem - it didn't. I've determined that I have no voltage on my tachometer circuit as tested at the gray terminal of the terminal strip next to the regulator/recitifier. The manual says to perform this tachometer circuit test if the boat's tachometer is not working (it is not) or if the VRO "no oil" warniing signal is in question (it started failing a couple years ago). The manual does not explain what to do if the tach circuit does not test ok. I'm wondering what do I do next? (btw, the stator checks out ok)

 

[DargelJohn]

Re: no volts on tach circuit

The gray wire is your pulse signal from the stator. The purple wire is your "switched" positive. Key needs to be turned on for power.

 

[bayprowler]

Re: no volts on tach circuit

yes I understand. no volts on the gray wire pulse signal when power switched on and motor running. is this at all linked to the VRO warning horn?

 

[boobie]

Re: no volts on tach circuit

When the mtr is running, try disconnecting the wires going to the vro warning system and see what happens to your tach.

 

[Chris1956]

Re: no volts on tach circuit

The grey wire will have some AC voltage on it when the motor is running. This is what the tach counts to give an RPM reading.

 

[boobie]

Re: no volts on tach circuit

If you have a peak reading volt meter or DVA adapter you should get 8 volts plus.