# Tach troubles in a 72 510



## hedcase510 (Jul 22, 2005)

Just hooked up my autometer tach in my 72 510. I hooked the green wire to the negative terminal of my coil, and the other wires are hooked up accordingly. The tach shows idle just fine, but as I increase the RPMs, it only goes up to like 3K when the engine sounds like it's revved out. Anyone had this problem before?


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## nizmo559 (Mar 4, 2003)

On my autometer tack there is a switch in the back thats for switching from 4,6,8 cylinders. I'm guessing maybe if you have that switch its on the wrong setting. Check it out.

Other than that if you bought it used maybe its blown out or something.


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## hedcase510 (Jul 22, 2005)

There's no switch on the back. I was told I needed an adapter from Autometer... but the adapters are for distributerless ignition systems, so thats not gonna help.


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## nizmo559 (Mar 4, 2003)

I have never had to use a adapter on my datsuns. Did you buy that tach new or used from somebody? Maybe get your money back if you can and try a different model. Recheck all your wires just to be sure.


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## fastredminx (Aug 20, 2005)

*tach*

depending on what model you have, you would have to take of the back cover off....should be one screw...and you'll see the switch to select 4,6 or 8 :thumbup: are you running a msd?


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## hedcase510 (Jul 22, 2005)

I've checked all the wires, and they're all good. The guy I bought it from had it on his dimer before me, and is helping me troubleshoot this problem via email. I'm not running electronic dist. Wierd. The only thing I can think of right now is I rebuilt my distributer and put in new points. Maybe the gaps are off and this is messing with the reading. I dunno? maybe the setting on the back of the tach is off the 4cyl selection... I'll try and take the back off tommorow and see. Thanks for the help guys!


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