Tach doesnt work, 1986 force 85 hp. 1972 glastron starflite.
The purple wire runs directly to the tach grey wire, and the black tach wire is grounded. Nothing happens at all on the tach needle. Is there a way to check this?
Is there a third terminal on the tach for power? Three terminal tachs need a 12 volt power source from the "I" ignition or run terminal of the ignition switch. Purple wire goes to signal and should be attached to an AC terminal on the rectifier on the engine end. Black is ground and needs to be grounded under the dash. AND, the tach needs to be a 20 pole tach.
Is there a third terminal on the tach for power? Three terminal tachs need a 12 volt power source from the "I" ignition or run terminal of the ignition switch. Purple wire goes to signal and should be attached to an AC terminal on the rectifier on the engine end. Black is ground and needs to be grounded under the dash. AND, the tach needs to be a 20 pole tach.
It is grounded under the dash, and no, there is no third terminal. The purple wire goes to a wire marked "tachometer" on the engine terminal block, and that wire goes to a little 1.5" square that has 4 wires going to it, and is marked AC. (rectifier?)
The tach label reads-
Altrnator tachometer gray ire to non regulated output side of alternator. Ground terminal to ground (MOTOR) OMC accessories, 121614
Has the tach ever worked for you? Have you checked your wiring? You should be able to do a search in this forum and find out how to test your rectifier.
