Technical tach not working

tried two tachs,,,,neither work....hooked up as per instructions....one sunpro and one autometer..........used tach wire from the wiring kit and also used power directly from battery. other wires one to neg. side of coil,one ground (good ground) one to light ....both tachs no readings. light does work........using a pertronix ignitor points elimanator. engine runs great battery in great condition....this ain't my first big job......but i'm stumped....any ideas ?????? thanks

 

Google pertronix tach not working, seems like a common issue. Good luck

 

I have a Sun Pro in my Ford, think it had 5 wires to hook up. I would just go over each wire and maybe put the ground elsewhere, run a jumper if you have to. If you put a lug on it, look at that closely as well. I lugged mine and grounded it to one of the dash supports, bare metal.

 

I have the same set up as you. With a sun pro I just hooked up the other day. You should have one white wire, one green, one red, one black and one blue. That makes 5 wires.

 

Motor needs to be running!

 

Or be satisfied with half the job done; if the car is off, then the tach is right. Sort of like a dead watch being right twice a day.

 

I'll go through my harness wiring and see how mine is hooked up.

 

Vintage Sun Super Tach ll have four wires. Green to minus side of coil, Black to ground, Red to 12 Volt power source, White or Blue is for the light. Your problem may be related to the Pertronix

Gary

 

I had a sunpro tack in my 74ford ranger xlt , well it got to be it would cutout at high speeds then one day it quit I mean the pickup just stopped , long story short turned out to be the tack unhooked it ran perfect

 

red=tach wire from harness......black=good ground white=light green=neg. side of coil
sun pro and auto meter tachs....

 

mine has 2 red wires, one black, one white w-red stripe. Anyone know how these wires go ? Mike