1972 Raylle Tach not Working

[tmirisola]

I have a 72 Challenger with the Raylle Factory Instrument Cluster. My Tach does not work. Where should I start looking/troubleshooting???

Thank You

[MEK-Dangerous]

It's common to have to get them rebuilt. There are only 3 things it needs. Power, ground, and a signal from the "+" side of the ignition coil. It gets it's ground connection from the dash frame, so I wouldn't suspect that. 

[JS29]

I think the tachometer gets the signal from the negative side of the coil. 

[MEK-Dangerous]

I think the tachometer gets the signal from the negative side of the coil. 

Yeah, I just came back to edit my brain fart. Thanks for catching that so soon.

[tmirisola]

OK, Where can I get the Tach rebuilt????

[JS29]

OK, Where can I get the Tach rebuilt????

@HEMICUDA  would probably know who would be your best bet.

[Chryco Psycho]

DO it yourself , RTE sells the kit easy to install , you need the calibration tool though to make it accurate

[usraptor]

I upgraded mine with the RTE kit and did the calibration.  It works, but is very slow to register the increase in RPMs. I have to shift long before it gets to 5K RPM.

[MEK-Dangerous]

I was lazy and sent mine out for rebuild.

   http://www.performancecargraphics.com/Dash_Stuff/Restoration/70-74_E-body_Rallye.htm