I just got a '73gmc, and it has a tach in it, but it doesn't work, actaully it isn't connected, how can i connect this, didn't see anything under the dash that plugged in there. I want to just run new wires, so does anyone know how I can do this? Where do the wire run to?
are your running an HEI ignition?? is this a factory electric tach? If so, you should be able to pull gauge cluster out, look for a single male connecter marked "tach" .. if you have hei all you have to do is run wire from this connecter to the tach connection on the HEI ..(next to the battery connection on the cap) that is if it has been converted already... we hope. if this is an aftermarket tach you should have one for ground(black), one for power(red), one for the light(white) if it is so equipped, and one that plugs into the HEI..(green) If memory serves correct.. hope this helps. if this doesn't help, list your setup and I will see if I can figure it out.. I need the type of ignition (points or HEI) type of tach(mechanical,electric,stock, aftermarket) eugene68
Hey thanks for the reply, I just have regular points on my truck, and the tach is stock . There is 3 male connectors on the back of the tach. And I couldn't find the female connector anywhere. I beleive that this instrument cluster is from another truck , so I probably need to run new wires.
The stock tach was offered in 73. I'm not exactly positive about a female plug from the wiring harness, but the factory tach option is directly related to your fuel gauge. I'm thinking the tach plugs into the fuel gauge or is connected in some fashion. Look at or around the fuel gauge for a female tach connection.
O.k. I will check for that, I don't recall seeing one before, I have had that instrument cluster out a few times now, and don't recall seeing anything, but when you don't know where to look, it makes it tougher. I'll take another look on the weekend when I have more time. Also I noticed a wire coming from the coil , then it goes from there into the back of the fuse panel on the firewall, could this be one of the wires I should follow?
I read a tech section on tach's in our trucks on 73-87.com. It told me exactly what I needed to know. Didn't notice before, but beside the 3 prongs on the back of the tach, they are labelled to where they go!! So I hooked it up and it is working great. Thanks all for your responses.
