Evinrude Tac not working

[rk20fisher]

I have a 1987 Evinrude 90hp which the tac is not working on. I have replaced the regulator/rectifier which seems to be charging properly, and the tac seems to be getting voltage when the switch is turned on but the tac does not register. My question is what pole should the tac be set at and is there any other test that can be done on the tac?

 

[jonesg]

Re: Evinrude Tac not working

The factory manual advises to test the tach by swapping it with a known good one, fat lot of help that is eh?
They do go south after a few yrs.

 

[ezeke]

Re: Evinrude Tac not working

It should be set for 6p.

Try running a temporary gray wire from the teminal block to the 'S' post on the gauge; your gray wire may be compromised in the harness.

The ground is critical, so check that as well.

 

[rk20fisher]

Re: Evinrude Tac not working

I have checked all of the wires on the back of the tack and all seem to be getting voltage like they are supposed to. I will change the setting to the 6p setting and give it another shot.

 

[rk20fisher]

Re: Evinrude Tac not working

I have tested all of the wires with the setting at 6p, the readings are 12.43v on the ignition, 4.32 on the pulse with the motor running but I still have no reading on the tac. I do believe this means that the tac is bad, is that a correct assumption to make?

 

[wilde1j]

Re: Evinrude Tac not working

Most likely.

 

[rk20fisher]

Re: Evinrude Tac not working

Actually I think I got it fixed turns out that the wiring was crossed going into the plug, it now works.

Thanks for all the help!