1965 tach

[Mikelj5S230]

I am looking at the tach that is in my '65, which doesn't work, and it has a red wire (coil), a yellow wire (ignition), a blue wire which I don't know what it is, and 2 black wires on the same terminal, one connected to a ground bolt on the dash and another coming from the oil gauge light, I think. Anyone know what the blue wire is?  Thanks.

[Bob Gaines]

Picture is of page from SA factory installation manual.

[Bob Gaines]

From what you described the colored wires used on your car are different colors from what the factory used. For example the blue wire is meant to go from the marked 12V terminal in the picture to the ignition. Black is ground ,white wire from the marked terminal is for the light in the gauge. Red should be on the marked terminal and goes to the coil.     

[Mikelj5S230]

Thanks Bob!  The tach I have has the same look and terminals on the back, the yellow wire is what the white one is, I think, and tested as the ignition linked power. But the red and blue wires were connected to different terminals than what is shown on the diagram. The two black wires were connected to the terminal in the diagram that has no tag, above and between the blue and red terminals. I may try to connect it the way this diagram shows and see what happens. Thanks again.